Download User Manual for Stata Package DASP: Version 2.3

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USERMANUAL
DASPversion2.3
DASP:DistributiveAnalysisStataPackage
By
AbdelkrimAraar,
Jean‐YvesDuclos
UniversitéLaval
PEP,CIRPÉEandWorldBank
June2013
Tableofcontents
Tableofcontents............................................................................................................................. 2 ListofFigures .................................................................................................................................. 6 1 Introduction ............................................................................................................................ 8 2 DASPandStataversions ......................................................................................................... 8 3 InstallingandupdatingtheDASPpackage ........................................................................... 9 3.1 InstallingDASPmodules ................................................................................................ 9 3.2 AddingtheDASPsubmenutoStata’smainmenu ...................................................... 10 4 DASPanddatafiles ............................................................................................................... 10 5 Mainvariablesfordistributiveanalysis ............................................................................. 11 6 HowcanDASPcommandsbeinvoked? .............................................................................. 11 7 HowcanhelpbeaccessedforagivenDASPmodule? ....................................................... 12 8 ApplicationsandfilesinDASP ............................................................................................. 12 9 BasicNotation ....................................................................................................................... 14 10 DASPandpovertyindices ................................................................................................ 14 10.1 FGTandEDE‐FGTpovertyindices(ifgt)..................................................................... 14 10.2 DifferencebetweenFGTindices(difgt) ...................................................................... 15 10.3 Wattspovertyindex(iwatts). ...................................................................................... 16 10.4 DifferencebetweenWattsindices(diwatts) .............................................................. 16 10.5 Sen‐Shorrocks‐Thonpovertyindex(isst). ................................................................. 17 10.6 DifferencebetweenSen‐Shorrocks‐Thonindices(disst) ......................................... 17 10.7 DASPandmultidimensionalpovertyindices ............................................................. 17 10.8 Multipleoverlappingdeprivationanalysis(MODA)indices ..................................... 19 11 DASP,povertyandtargetingpolicies ............................................................................... 20 11.1 Povertyandtargetingbypopulationgroups ............................................................. 20 11.2 Povertyandtargetingbyincomecomponents ......................................................... 21 12 Marginalpovertyimpactsandpovertyelasticities........................................................ 22 12.1 FGTelasticity’swithrespecttotheaverageincomegrowth(efgtgr). ..................... 22 12.2 FGTelasticitieswithrespecttoaverageincomegrowthwithdifferentapproaches
(efgtgro). .................................................................................................................................... 23 12.3 FGTelasticitywithrespecttoGiniinequality(efgtineq)........................................... 23 12.4 FGTelasticitywithrespecttoGini‐inequalitywithdifferentapproaches(efgtine).
24 12.5 FGTelasticitieswithrespecttowithin/betweengroupcomponentsofinequality
(efgtg)......................................................................................................................................... 25 12.6 FGTelasticitieswithrespecttowithin/betweenincomecomponentsofinequality
(efgtc). ........................................................................................................................................ 26 13 DASPandinequalityindices ............................................................................................ 28 13.1 Giniandconcentrationindices(igini) ........................................................................ 28 13.2 DifferencebetweenGini/concentrationindices(digini) .......................................... 28 13.3 Generalisedentropyindex(ientropy) ........................................................................ 29 13.4 Differencebetweengeneralizedentropyindices(diengtropy)................................ 29 13.5 Atkinsonindex(iatkinson) ......................................................................................... 30 13.6 DifferencebetweenAtkinsonindices(diatkinson) .................................................. 30 2
13.7 Coefficientofvariationindex(icvar) .......................................................................... 31 13.8 Differencebetweencoefficientofvariation(dicvar)................................................. 31 13.9 Quantile/shareratioindicesofinequality(inineq) .................................................. 31 13.10 DifferencebetweenQuantile/Shareindices(dinineq).......................................... 32 13.11 TheAraar(2009)multidimensionalinequalityindex........................................... 32 14 DASPandpolarizationindices ......................................................................................... 32 14.1 TheDERindex(ipolder) .............................................................................................. 32 14.2 DifferencebetweenDERpolarizationindices(dipolder) ......................................... 33 14.3 TheFosterandWolfson(1992)polarizationindex(ipolfw) ................................... 34 14.4 DifferencebetweenFosterandWolfson(1992)polarizationindices(dipolfw) .... 34 14.5 TheGeneralisedEsteban,GradinandRay(1999)polarisationindex(ipoger) ...... 34 14.6 TheInaki(2008)polarisationindex(ipoger) ............................................................ 36 15 DASPanddecompositions................................................................................................ 39 15.1 FGTPoverty:decompositionbypopulationsubgroups(dfgtg) ............................... 39 15.2 FGTPoverty:decompositionbyincomecomponentsusingtheShapleyvalue
(dfgts) 40 15.3 AlkireandFoster(2011)MDindexofpoverty:decompositionbypopulation
subgroups(dmdafg) ................................................................................................................. 42 15.4 AlkireandFoster(2011:decompositionbydimensionsusingtheShapleyvalue
(dmdafs) .................................................................................................................................... 42 15.5 FGTPoverty:decompositionbyincomecomponentsusingtheShapleyvalue
(dfgts) 43 15.6 DecompositionofthevariationinFGTindicesintogrowthandredistribution
components(dfgtgr)................................................................................................................. 45 15.7 DecompositionofchangeinFGTpovertybypovertyandpopulationgroup
components–sectoraldecomposition‐(dfgtg2d). ................................................................. 46 15.8 DecompositionofFGTpovertybytransientandchronicpovertycomponents
(dtcpov) ..................................................................................................................................... 49 15.9 Inequality:decompositionbyincomesources(diginis) ........................................... 51 15.10 Regression‐baseddecompositionofinequalitybyincomesources..................... 52 15.11 Giniindex:decompositionbypopulationsubgroups(diginig). ........................... 58 15.12 Generalizedentropyindicesofinequality:decompositionbypopulation
subgroups(dentropyg). ........................................................................................................... 59 15.13 Polarization:decompositionoftheDERindexbypopulationgroups(dpolag).. 59 15.14 Polarization:decompositionoftheDERindexbyincomesources(dpolas) ....... 60 16 DASPandcurves................................................................................................................ 60 16.1 FGTCURVES(cfgt). ....................................................................................................... 60 16.2 FGTCURVEwithconfidenceinterval(cfgts). ............................................................. 62 16.3 DifferencebetweenFGTCURVESwithconfidenceinterval(cfgts2d). .................... 62 16.4 LorenzandconcentrationCURVES(clorenz). ............................................................ 62 16.5 Lorenz/concentrationcurveswithconfidenceintervals(clorenzs). ....................... 63 16.6 DifferencesbetweenLorenz/concentrationcurveswithconfidenceinterval
(clorenzs2d) .............................................................................................................................. 64 16.7 Povertycurves(cpoverty) ........................................................................................... 64 16.8 Consumptiondominancecurves(cdomc) .................................................................. 65 16.9 Difference/Ratiobetweenconsumptiondominancecurves(cdomc2d) ................. 66 3
16.10 DASPandtheprogressivitycurves ......................................................................... 66 16.10.1 Checkingtheprogressivityoftaxesortransfers .............................................. 66 16.10.2 Checkingtheprogressivityoftransfervstax ................................................... 67 17 Dominance......................................................................................................................... 67 17.1 Povertydominance(dompov) ..................................................................................... 67 17.2 Inequalitydominance(domineq)................................................................................ 68 17.3 DASPandbi‐dimensionalpovertydominance(dombdpov) .................................... 68 18 Distributivetools .............................................................................................................. 69 18.1 Quantilecurves(c_quantile) ........................................................................................ 69 18.2 Incomeshareandcumulativeincomesharebygroupquantiles(quinsh) ............. 69 18.3 Densitycurves(cdensity) ............................................................................................ 69 18.4 Non‐parametricregressioncurves(cnpe) ................................................................. 71 18.4.1 Nadaraya‐Watsonapproach ................................................................................ 71 18.4.2 Locallinearapproach ........................................................................................... 71 18.5 DASPandjointdensityfunctions. ............................................................................... 71 18.6 DASPandjointdistributionfunctions ........................................................................ 72 19 DASPandpro‐poorgrowth .............................................................................................. 72 19.1 DASPandpro‐poorindices .......................................................................................... 72 19.2 DASPandpro‐poorcurves ........................................................................................... 73 19.2.1 Primalpro‐poorcurves ........................................................................................ 73 19.2.2 Dualpro‐poorcurves ........................................................................................... 74 20 DASPandBenefitIncidenceAnalysis .............................................................................. 75 20.1 Benefitincidenceanalysis ............................................................................................ 75 21 Disaggregatinggroupeddata ........................................................................................... 79 22 Appendices ........................................................................................................................ 83 22.1 AppendixA:illustrativehouseholdsurveys ............................................................... 83 22.1.1 The1994BurkinaFasosurveyofhouseholdexpenditures(bkf94I.dta) ........ 83 22.1.2 The1998BurkinaFasosurveyofhouseholdexpenditures(bkf98I.dta) ........ 84 22.1.3 CanadianSurveyofConsumerFinance(asubsampleof1000observations–
can6.dta) ................................................................................................................................ 84 22.1.4 PeruLSMSsurvey1994(Asampleof3623householdobservations‐
PEREDE94I.dta) .................................................................................................................... 84 22.1.5 PeruLSMSsurvey1994(Asampleof3623householdobservations–
PERU_A_I.dta)........................................................................................................................ 85 22.1.6 The1995ColombiaDHSsurvey(columbiaI.dta)............................................... 85 22.1.7 The1996DominicanRepublicDHSsurvey(Dominican_republic1996I.dta) . 85 22.2 AppendixB:labellingvariablesandvalues ................................................................ 86 22.3 AppendixC:settingthesamplingdesign .................................................................... 87 23 Examplesandexercises ................................................................................................... 89 23.1 EstimationofFGTpovertyindices .............................................................................. 89 23.2 EstimatingdifferencesbetweenFGTindices. ............................................................ 95 23.3 Estimatingmultidimensionalpovertyindices ........................................................... 99 23.4 EstimatingFGTcurves................................................................................................ 102 23.5 EstimatingFGTcurvesanddifferencesbetweenFGTcurveswithconfidence
intervals ................................................................................................................................... 110 23.6 Testingpovertydominanceandestimatingcriticalvalues..................................... 114 4
23.7 DecomposingFGTindices. ......................................................................................... 115 23.8 EstimatingLorenzandconcentrationcurves........................................................... 118 23.9 EstimatingGiniandconcentrationcurves ............................................................... 124 23.10 Usingbasicdistributivetools ................................................................................ 128 23.11 Plottingthejointdensityandjointdistributionfunction ................................... 134 23.12 Testingthebi‐dimensionalpovertydominance .................................................. 137 23.13 Testingforpro‐poornessofgrowthinMexico..................................................... 140 23.14 BenefitincidenceanalysisofpublicspendingoneducationinPeru(1994). .... 146 5
ListofFigures
Figure1:Ouputofnetdescribedasp..................................................................................................................9
Figure2:DASPsubmenu......................................................................................................................................10
Figure3:UsingDASPwithacommandwindow.......................................................................................11
Figure4:AccessinghelponDASP....................................................................................................................12
Figure5:EstimatingFGTpovertywithonedistribution......................................................................13
Figure6:EstimatingFGTpovertywithtwodistributions....................................................................13
Figure7:Povertyandthetargetingbypopulationgroups..................................................................21
Figure8:DecompositionoftheFGTindexbygroups.............................................................................39
Figure9:DecompositionofFGTbyincomecomponents......................................................................44
Figure10:SectoraldecompositionofFGT..................................................................................................48
Figure11:Decompositionofpovertyintotransientandchroniccomponents...........................50
Figure12:DecompositionoftheGiniindexbyincomesources(Shapleyapproach)..............52
Figure13:FGTcurves...........................................................................................................................................61
Figure14:Lorenzandconcentrationcurves..............................................................................................63
Figure15:Consumptiondominancecurves...............................................................................................66
Figure16:ungroupdialogbox..........................................................................................................................82
Figure17:Surveydatasettings........................................................................................................................87
Figure18:Settingsamplingweights..............................................................................................................88
Figure19:EstimatingFGTindices...................................................................................................................91
Figure20:EstimatingFGTindiceswithrelativepovertylines...........................................................92
Figure21:FGTindicesdifferentiatedbygender......................................................................................93
Figure22:EstimatingdifferencesbetweenFGTindices.......................................................................96
Figure23:EstimatingdifferencesinFGTindices.....................................................................................97
Figure24:FGTdifferencesacrossyearsbygenderandzone.............................................................98
Figure25:Estimatingmultidimensionalpovertyindices(A)..........................................................100
Figure26:Estimatingmultidimensionalpovertyindices(B)..........................................................101
Figure27:DrawingFGTcurves.....................................................................................................................103
Figure28:EditingFGTcurves........................................................................................................................103
Figure29:GraphofFGTcurves.....................................................................................................................104
Figure30:FGTcurvesbyzone.......................................................................................................................105
Figure31:GraphofFGTcurvesbyzone....................................................................................................106
Figure32:DifferencesofFGTcurves..........................................................................................................107
Figure33:Listingcoordinates.......................................................................................................................108
Figure34:DifferencesbetweenFGTcurves............................................................................................109
Figure35:DifferencesbetweenFGTcurves............................................................................................110
Figure36:DrawingFGTcurveswithconfidenceinterval.................................................................111
Figure37:FGTcurveswithconfidenceinterval....................................................................................112
Figure38:DrawingthedifferencebetweenFGTcurveswithconfidenceinterval.................113
Figure39:DifferencebetweenFGTcurveswithconfidenceinterval (  0) ...........................113
Figure40:DifferencebetweenFGTcurveswithconfidenceinterval (  1) ...........................114
Figure41:Testingforpovertydominance...............................................................................................115
Figure42:DecomposingFGTindicesbygroups....................................................................................116
Figure43:Lorenzandconcentrationcurves...........................................................................................119
6
Figure44:Lorenzcurves..................................................................................................................................120
Figure45:Drawingconcentrationcurves................................................................................................121
Figure46:Lorenzandconcentrationcurves...........................................................................................122
Figure47:DrawingLorenzcurves...............................................................................................................123
Figure48:Lorenzcurves..................................................................................................................................123
Figure49:EstimatingGiniandconcentrationindices.........................................................................125
Figure50:Estimatingconcentrationindices...........................................................................................126
Figure51:EstimatingdifferencesinGiniandconcentrationindices...........................................127
Figure52:Drawingdensities..........................................................................................................................128
Figure53:Densitycurves.................................................................................................................................129
Figure54:Drawingquantilecurves............................................................................................................130
Figure55:Quantilecurves...............................................................................................................................130
Figure56:Drawingnon‐parametricregressioncurves......................................................................131
Figure57:Non‐parametricregressioncurves........................................................................................132
Figure58:Drawingderivativesofnon‐parametricregressioncurves........................................133
Figure59:Derivativesofnon‐parametricregressioncurves...........................................................133
Figure60:Plottingjointdensityfunction.................................................................................................134
Figure61:Plottingjointdistributionfunction........................................................................................136
Figure62:Testingforbi‐dimensionalpovertydominance...............................................................138
Figure63:Testingthepro‐poorgrowth(primalapproach).............................................................141
Figure64:Testingthepro‐poorgrowth(dualapproach)‐A............................................................142
Figure65:Testingthepro‐poorgrowth(dualapproach)–B..........................................................144
Figure66:Benefitincidenceanalysis..........................................................................................................147
Figure67:BenefitIncidenceAnalysis(unitcostapproach).............................................................149
7
1
Introduction
TheStatasoftwarehasbecomeaverypopulartooltotransformandprocessdata.Itcomeswitha
largenumberofbasicdatamanagementmodulesthatarehighlyefficientfortransformationoflarge
datasets.TheflexibilityofStataalsoenablesprogrammerstoprovidespecialized“.ado”routinesto
addtothepowerofthesoftware.ThisisindeedhowDASPinteractswithStata.DASP,whichstands
forDistributiveAnalysisStataPackage,ismainlydesignedtoassistresearchersandpolicyanalysts
interestedinconductingdistributiveanalysiswithStata.Inparticular,DASPisbuiltto:

Estimatethemostpopularstatistics(indices,curves)usedfortheanalysisofpoverty,
inequality,socialwelfare,andequity;

Estimatethedifferencesinsuchstatistics;

Estimatestandarderrorsandconfidenceintervalsbytakingfullaccountofsurvey
design;

Supportdistributiveanalysisonmorethanonedatabase;

Performthemostpopularpovertyanddecompositionprocedures;

Checkfortheethicalrobustnessofdistributivecomparisons;

Unifysyntaxandparameteruseacrossvariousestimationproceduresfordistributive
analysis.
ForeachDASPmodule,threetypesoffilesareprovided:
*.ado: Thisfilecontainstheprogramofthemodule
*.hlp: Thisfilecontainshelpmaterialforthegivenmodule
*.dlg: Thisfileallowstheusertoperformtheestimationusingthe
module’sdialogbox
The *.dlg files in particular makes the DASP package very user friendly and easy to learn. When
these dialog boxes are used, the associated program syntax is also generated and showed in the
reviewwindow.Theusercansavethecontentsofthiswindowina*.dofiletobesubsequentlyused
inanothersession.
2
DASPandStataversions
DASPrequires
o Stataversion10.0orhigher
o adofilesmustbeupdated
Toupdatetheexecutablefile(from10.0to10.2)andtheadofiles,see:
http://www.stata.com/support/updates/
8
3
InstallingandupdatingtheDASPpackage
Ingeneral,the*.adofilesaresavedinthefollowingmaindirectories:
Priority Directory
Sources
1
UPDATES:
OfficialupdatesofStata *.adofiles
2
BASE:
*.adofilesthatcomewiththeinstalledStata software
3
SITE:
*.adofilesdownloadedfromthenet
4
PLUS:
..
5
PERSONAL:
Personal*.adofiles
3.1
InstallingDASPmodules
a. Unzipthefiledasp.zipinthedirectoryc:
b. Makesurethatyouhavec:/dasp/dasp.pkgorc:/dasp/stata.toc
c. IntheStatacommandwindows,typethesyntax
netfromc:/dasp
Figure1:Ouputofnetdescribedasp
d.
Typethesyntax
netinstalldasp_p1.pkg,forcereplace
netinstalldasp_p2.pkg,forcereplace
netinstalldasp_p3.pkg,forcereplace
netinstalldasp_p4.pkg,forcereplace
9
3.2 AddingtheDASPsubmenutoStata’smainmenu
WithStata9,submenuscanbeaddedtothemenuitemUser.
Figure2:DASPsubmenu
ToaddtheDASPsubmenus,thefileprofile.do(whichisprovidedwiththeDASPpackage)mustbe
copiedintothePERSONALdirectory.Ifthefileprofile.doalreadyexists,addthecontentsofthe
DASP–providedprofile.dofileintothatexistingfileandsaveit.Tocheckifthefileprofile.do
alreadyexists,typethecommand:findfileprofile.do.
4
DASPanddatafiles
DASP makes it possible to use simultaneously more than one data file. The user should, however,
“initialize”eachdatafilebeforeusingitwithDASP.Thisinitializationisdoneby:
1. Labelingvariablesandvaluesforcategoricalvariables;
2. Initializingthesamplingdesignwiththecommandsvyset;
3. Savingtheinitializeddatafile.
UsersarerecommendedtoconsultappendicesA,BandC,
10
5
Mainvariablesfordistributiveanalysis
VARIABLEOFINTEREST.Thisisthevariablethatusuallycaptureslivingstandards.Itcanrepresent,for
instance, income per capita, expenditures per adult equivalent, calorie intake, normalized height‐
for‐agescoresforchildren,orhouseholdwealth.
SIZEVARIABLE.Thisreferstothe"ethical"orphysicalsizeoftheobservation.Forthecomputationof
many statistics, we will indeed wish to take into account how many relevant individuals (or
statisticalunits)arefoundinagivenobservation.
GROUPVARIABLE.(ThisshouldbeusedincombinationwithGROUPNUMBER.)Itisoftenusefultofocus
one’s analysis on some population subgroup. We might, for example, wish to estimate poverty
withinacountry’sruralareaorwithinfemale‐headedfamilies.OnewaytodothisistoforceDASP
to focus on a population subgroup defined as those for whom some GROUP VARIABLE (say, area of
residence)equalsagivenGROUPNUMBER(say2,forruralarea).
SAMPLINGWEIGHT.Samplingweightsaretheinverseofthesamplingprobability.Thisvariableshould
besetupontheinitializationofthedataset.
6
HowcanDASPcommandsbeinvoked?
Statacommandscanbeentereddirectlyintoacommandwindow:
Figure3:UsingDASPwithacommandwindow
11
Analternativeistousedialogboxes.Forthis,thecommanddbshouldbetypedandfollowedbythe
nameoftherelevantDASPmodule.
Example:
dbifgt
7
HowcanhelpbeaccessedforagivenDASPmodule?
TypethecommandhelpfollowedbythenameoftherelevantDASPmodule.
Example:
helpifgt
Figure4:AccessinghelponDASP
8
ApplicationsandfilesinDASP
TwomaintypesofapplicationsareprovidedinDASP.Forthefirstone,theestimationprocedures
requireonlyonedatafile.Insuchcases,thedatafileinmemoryistheonethatisused(or“loaded”);
itisfromthatfilethattherelevantvariablesmustbespecifiedbytheusertoperformtherequired
estimation.
12
Figure5:EstimatingFGTpovertywithonedistribution
Forthesecondtypeofapplications,twodistributionsareneeded.Foreachofthesetwo
distributions,theusercanspecifythecurrently‐loadeddatafile(theoneinmemory)oronesaved
ondisk.
Figure6:EstimatingFGTpovertywithtwodistributions
13
Notes:
1. DASPconsiderstwodistributionstobestatisticallydependent(forstatisticalinference
purposes)ifthesamedatasetisused(thesameloadeddataordatawiththesamepathand
filename)forthetwodistributions.
2. IftheoptionDATAINFILEischosen,thekeyboardmustbeusedtotypethenameofthe
requiredvariables.
9
BasicNotation
ThefollowingtablepresentsthebasicnotationusedinDASP’susermanual.
Symbol
Indication
y
variableofinterest
i
observationnumber
yi
valueofthevariableofinterestforobservationi
hw
samplingweight
hwi
samplingweightforobservationi
hs
sizevariable
hsi
sizeofobservationi(forexamplethesizeofhouseholdi)
wi
hwi*hsi
hg
groupvariable
hgi
groupofobservationi.
wik
swik=swiifhgi=k,and0otherwise.
n
samplesize
Forexample,themeanofyisestimatedbyDASPas ̂ :
n
ˆ 
w y
i 1
n
i
i
w
i
i 1
10 DASPandpovertyindices
10.1
FGTandEDE‐FGTpovertyindices(ifgt).
Thenon‐normalisedFoster‐Greer‐ThorbeckeorFGTindexisestimatedas
n

 wi ( z  yi )
 z; )  i 1
P(
n
 wi
i 1
wherezisthepovertylineand x  max( x, 0) .TheusualnormalisedFGTindexisestimatedas

 ( z;  ) /( z ) P ( z;  )  P
14
TheEDE‐FGTindexisestimatedas:


 ( P( z;  ))  P
 ( z;  ) 1/ 
EDE
for  > 0

Thereexistthreewaysoffixingthepovertyline:


1‐Settingadeterministicpovertyline;
2‐Settingthepovertylinetoaproportionofthemean;
3‐SettingthepovertylinetoaproportionofaquantileQ(p).
Theusercanchoosethevalueofparameter  .
Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimatepovertybyusingsimultaneouslypercapitaconsumptionandpercapitaincome.

Agroupvariablecanbeusedtoestimatepovertyatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.

Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.1
10.2
DifferencebetweenFGTindices(difgt)
ThismoduleestimatesdifferencesbetweentheFGTindicesoftwodistributions.
Foreachofthetwodistributions:
 Thereexistthreewaysoffixingthepovertyline:
1‐Settingadeterministicpovertyline;
2‐Settingthepovertylinetoaproportionofthemean;
3‐SettingthepovertylinetoaproportionofaquantileQ(p)
 Onevariableofinterestshouldbeselected.
 Conditionscanbespecifiedtofocusonspecificpopulationsubgroups.
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
 Alevelfortheparameter  canbechosenforeachofthetwodistributions.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.2.
15
10.3
Wattspovertyindex(iwatts).
TheWattspovertyindexisestimatedas
q
 wi (ln( z / yi )
 z )  i 1
P(
n
 wi
i 1
wherezisthepovertylineand q thenumberofpoor.
 Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimatepovertybyusingsimultaneouslypercapitaconsumptionandpercapitaincome.
 Agroupvariablecanbeusedtoestimatepovertyatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
10.4
DifferencebetweenWattsindices(diwatts)
ThismoduleestimatesdifferencesbetweentheWattsindicesoftwodistributions.
Foreachofthetwodistributions:
 Onevariableofinterestshouldbeselected.
 Conditionscanbespecifiedtofocusonspecificpopulationsubgroups.
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
 Alevelfortheparameter  canbechosenforeachofthetwodistributions.
16
10.5
Sen‐Shorrocks‐Thonpovertyindex(isst).
TheSen‐Shorroks‐Thonpovertyindexisestimatedas:
 z )  HP* ( z, )[ 1  G* ] P(
g
wherezisthepovertyline H istheheadcount, P* ( z, ) thepovertygapestimatedatthelevelof
poorgroupand G*g theGiniindexofpovertygaps ( z  y ) / z .

Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimatepovertybyusingsimultaneouslypercapitaconsumptionandpercapitaincome.

Agroupvariablecanbeusedtoestimatepovertyatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.

Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.

Theresultsaredisplayedwith6decimals;thiscanbechanged.
10.6
DifferencebetweenSen‐Shorrocks‐Thonindices(disst)
ThismoduleestimatesdifferencesbetweentheWattsindicesoftwodistributions.
Foreachofthetwodistributions:
 Onevariableofinterestshouldbeselected.
 Conditionscanbespecifiedtofocusonspecificpopulationsubgroups.
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
 Alevelfortheparameter  canbechosenforeachofthetwodistributions.
10.7 DASPandmultidimensionalpovertyindices
Thegeneralformofanadditivemultidimensionalpovertyindexis:
17
n
P( X , Z ) 
 wi p( X i , Z )
i 1
n
 wi
i 1


where p ( X i , Z ) isindividualI’spovertyfunction(withvectorofattributes X i  xi ,1 ,..., xi , J and
vectorofpovertylines Z   z1 ,..., z J  ),determiningI’scontributiontototalpoverty P ( X , Z ) .
[1]Chakravartyetal(1998)index(imdp_cmr)
 z j  xi , j
p( X i , Z )   a j 
 zj
j 1

J


 
[2]ExtendedWattsindex(imdp_ewi)
J


zj
p( X i , Z )   a j ln 
 min( z j ; xi , j ) 
j 1


[3]MultiplicativeextendedFGTindex(imdp_mfi)
 z j  xi , j
p( X i , Z )   
 zj
j 1 
[4]Tsui(2002)index(imdp_twu)
J

 j
 
b

 j
zj
p( X i , Z )   
  1 
j 1  min( z j ; xi , j ) 
J
[5]Intersectionheadcountindex(imdp_ihi)
J


p( X i , Z )   I z j  xi , j j 1
[6]Unionheadcountindex(imdp_uni)
J


p( X i , Z )  1   I z j  xi , j j 1
[7]BourguignonandChakravartybi‐dimensional(2003)index(imdp_bci)
18



p ( X i , Z )  C1    C2 




where:


z x 
z x 
C1  1 i ,1  and C2  2 i ,2   z1 
 z2  
[8]AlkireandFoster(2011)index(imdp_afi)
1
p( , X i , Z ) 
N
 z j  xi , j
1 J
w
 J  j  z
j
i
j 1

N


 I (di  d c ) 
J
where
 w j  J and di denotesthenumberofdimensionsinwhichtheindividual i isdeprived.
j 1
dc denotesthenormativedimensionalcut‐off.
Themodulespresentedabovecanbeusedtoestimatethemultidimensionalpovertyindicesaswell
astheirstandarderrors.
 Theusercanselectamongthesevenmultidimensionalpovertyindices.
 Thenumberofdimensionscanbeselected(1to10).
 Ifapplicable,theusercanchooseparametervaluesrelevanttoachosenindex.
 Agroupvariablecanbeusedtoestimatetheselectedindexatthelevelofacategorical
group.
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith3decimals;thiscanbealsochanged.
UsersareencouragedtoconsidertheexercisesthatappearinSection23.3
10.8
Multipleoverlappingdeprivationanalysis(MODA)indices
TheimodaDASPmoduleproducesaseriesofmultidimensionalpovertyindicesinorderto
show the incidence of deprivation in each dimension. Further, this application estimates the
incidenceofmulti‐deprivationinthedifferentcombinationsofdimensions.Inthisapplication,the
number of dimensions is set to three. Further, the multidimensional poverty is measured by the
headcount(union andintersectionheadcountindices)andtheAlkire andFoster(2011) M0index
fordifferentlevelsofthedimensionalcut‐off.
19
 Thenumberofdimensionsisthree.
 AgroupvariablecanbeusedtoestimatetheMODAindicesatthelevelofacategorical
group.
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith3decimals;thiscanbealsochanged.
11 DASP,povertyandtargetingpolicies
11.1
Povertyandtargetingbypopulationgroups
Theper‐capitadollarimpactofamarginaladditionofaconstantamountofincometoeveryone
withinagroupk–calledLump‐SumTargeting(LST)–ontheFGTpovertyindex P(k, z; ) ,isas
follows:
P(k, z;   1) if   1
LST  
if   0
f (k, z)
where z isthepovertyline,kisthepopulationsubgroupforwhichwewishtoassesstheimpactof
theincomechange,and f (k , z ) isthedensityfunctionofthegroup k atlevelofincome z .Theper‐
capitadollarimpactofaproportionalmarginalvariationofincomewithinagroupk,called
InequalityNeutralTargeting,ontheFGTpovertyindex P(k, z;  ) isasfollows:
 P(k, z; )  zP(k, z;   1)
if   1

(k)

INT  
zf
(k,
z)

if   0
 (k)
Themoduleitargetgallowsto:
 Estimatetheimpactofmarginalchangeinincomeofthegrouponpovertyofthegroupand
thatofthepopulation;
 Selectthedesignofchange,constantorproportionaltoincometokeepinequality
unchanged;
 Drawcurvesofimpactaccordingforarangeofpovertylines;
 Drawtheconfidenceintervalofimpactcurvesorthelowerorupperboundofconfidence
interval;
 Etc.
20
Figure 7: Poverty and the targeting by population groups
Reference:
DUCLOS,J.‐Y.ANDA.ARAAR(2006):PovertyandEquityMeasurement,Policy,andEstimationwith
DAD,BerlinandOttawa:SpringerandIDRC.(sec.12.1)
11.2
Povertyandtargetingbyincomecomponents
Proportional change per 100% of component
Assume that total income Y is the sum of J income components, with Y 
J
 y
j 1
j
j
and where c is a factor
that multiplies income component y j and that can be subject to growth. The derivative of the normalized
FGT index with respect to  j is given by
P(z, )
 j
 CD j (z, )
 j 1, j1J
where CDj is the Consumption dominance curve of component j.
Change per $ of component
The per-capita dollar impact of growth in the jth component on the normalized FGT index of the k th
group is as follows:
21
P(z, )
y j
 j
j
 CD (z, )
y j
j
where CD is the normalized consumption dominance curve of the component j.
Constant change per component
Simply we assume that the change concerns the group with component level greater than zero.
Thus, this is similar to targeting by the nonexclusive population groups.
Themoduleitargetcallowsto:
 Estimatetheimpactofmarginalchangeinincomecomponentonpoverty;
 Selecttheoptionnormalisedornonnormalisedbytheaverageofcomponent;
 Selectthedesignofchange,constant(lumpsum)orproportionaltoincometokeep
inequalityunchanged;
 Drawcurvesofimpactaccordingforarangeofpovertylines;
 Drawtheconfidenceintervalofimpactcurvesorthelowerorupperboundofconfidence
interval;
 Etc.
Reference:
DUCLOS,J.‐Y.ANDA.ARAAR(2006):PovertyandEquityMeasurement,Policy,andEstimationwith
DAD,BerlinandOttawa:SpringerandIDRC.(sec.12)
12 Marginalpovertyimpactsandpovertyelasticities
12.1
FGTelasticity’swithrespecttotheaverageincomegrowth(efgtgr).
The overall growth elasticity (GREL) of poverty, when growth comes exclusively from growth within a
group k (namely, within that group, inequality neutral), is given by:
 zf (k , z )
if   0
 F ( z )

GREL  
 P (k , z;  )  P (k , z;   1) if   1

P ( z,  )
where z is the poverty line, k is the population subgroup in which growth takes place, f (k , z ) is the
density function at level of income z of group k , and F ( z ) is the headcount.
22
Araar,AbdelkrimandJean‐YvesDuclos,(2007),Povertyandinequalitycomponents:
a micro framework, Working Paper: 07‐35. CIRPEE, Department of Economics,
UniversitéLaval.
Kakwani, N. (1993) "Poverty and economic growth with application to Côte
D’Ivoire",ReviewofIncomeandWealth,39(2):121:139.
ToestimatetheFGTelasticity’swithrespectaverageincomegrowththegrouporthewhole
population;
Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimatepovertybyusingsimultaneouslypercapitaconsumptionandpercapitaincome.
Agroupvariablecanbeusedtoestimatepovertyatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.





12.2
FGTelasticitieswithrespecttoaverageincomegrowthwithdifferentapproaches
(efgtgro).
The overall growth elasticity of poverty is estimated using one approach among the following list:
 The counterfactual approach;
 The marginal approach;
 The parameterized approach;
 The numerical approach;
The module efgtgroallowstheestimationofapovertyelasticityorsemi‐elasticitywithrespectto
growthwiththedifferentapproachesmentionedabove.Formoredetailsontheseapproaches,see:
Abdelkrim Araar, 2012. "Expected Poverty Changes with Economic Growth and
Redistribution,"Cahiersderecherche1222,CIRPEE.



ToestimateaFGTelasticity–semi‐elasticity‐withrespecttoaverageincomegrowthina
grouporinanentirepopulation;
Agroupvariablecanbeusedtoestimatepovertyatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
12.3
FGTelasticitywithrespecttoGiniinequality(efgtineq).
The overall growth elasticity (INEL) of poverty, when growth comes exclusively from change in
inequality within a group k , is given by:
23
  (k ) f (k , z )   (k )  z   (k )  (k ) C (k )
if   0
/

F ( z)
I


INEL  
 P (k , z;  )     (k )  z  / z  P (k , z;   1)  (k )  (k ) C (k )
if   1
/

P ( z,  )
I


where z is the poverty line, k is the population subgroup in which growth takes place, f (k , z ) is the
density function at level of income z for group k , and F ( z ) is the headcount. C (k ) is the concentration
coefficient of group k when incomes of the complement group are replaced by  (k ) . I denotes the
Gini index.
Araar,AbdelkrimandJean‐YvesDuclos,(2007),Povertyandinequalitycomponents:
a micro framework, Working Paper: 07‐35. CIRPEE, Department of Economics,
UniversitéLaval.
Kakwani, N. (1993) "Poverty and economic growth with application to Côte
D’Ivoire",ReviewofIncomeandWealth,39(2):121:139.





12.4
ToestimateaFGTelasticitywithrespecttoaverageincomegrowthinagrouporinan
entirepopulation;
Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimatepovertybyusingsimultaneouslypercapitaconsumptionandpercapitaincome.
Agroupvariablecanbeusedtoestimatepovertyatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
FGTelasticitywithrespecttoGini‐inequalitywithdifferentapproaches(efgtine).
The overall Gini-inequality elasticity of poverty can be estimated by using one approach among the
following list:
 The counterfactual approach;
 The marginal approach;
 The parameterized approach;
 The numerical approach;

The module efgtineallowstheestimationofapovertyelasticityorsemi‐elasticitywithrespectto
inequalitywiththedifferentapproachesmentionedabove.Formoredetailsontheseapproaches,
see:
Abdelkrim Araar, 2012. "Expected Poverty Changes with Economic Growth and
Redistribution,"Cahiersderecherche1222,CIRPEE.
24



12.5
ToestimateaFGTelasticity–semi‐elasticity‐withrespecttoinequality;
Agroupvariablecanbeusedtoestimatepovertyatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
FGTelasticitieswithrespecttowithin/betweengroupcomponentsofinequality
(efgtg).
ThismoduleestimatesthemarginalFGTimpactandFGTelasticitywithrespecttowithin/between
groupcomponentsofinequality.Agroupvariablemustbeprovided.Thismoduleismostlybasedon
AraarandDuclos(2007):
Araar,AbdelkrimandJean‐YvesDuclos,(2007),Povertyandinequalitycomponents:
a micro framework, Working Paper: 07‐35. CIRPEE, Department of Economics,
UniversitéLaval.
Toopenthedialogboxofthismodule,typethecommanddbefgtg.
AfterclickingonSUBMIT,thefollowingshouldbedisplayed:
25
(g)



12.6
FGTelasticitieswithrespecttowithin/betweenincomecomponentsofinequality
(efgtc).
ThismoduleestimatesthemarginalFGTimpactandFGTelasticitywithrespecttowithin/between
incomecomponentsofinequality.Alistofincomecomponentsmustbeprovided.Thismoduleis
mostlybasedonAraarandDuclos(2007):
Araar,AbdelkrimandJean‐YvesDuclos,(2007),Povertyandinequalitycomponents:
a micro framework, Working Paper: 07‐35. CIRPEE, Department of Economics,
UniversitéLaval.
Toopenthedialogboxofthismodule,typethecommanddbefgtc.
26
AfterclickingonSUBMIT,thefollowingshouldbedisplayed:
(k)


Incaseoneisinterestedinchangingsomeincomecomponentonlyamongthoseindividualsthatare
effectivelyactiveinsomeeconomicsectors(schemes * (k), *and * inthepapermentioned
above),theusershouldselecttheapproach“Truncatedincomecomponent”.
27
13 DASPandinequalityindices
13.1
Giniandconcentrationindices(igini)
TheGiniindexisestimatedas
ˆ
Iˆ  1  ˆ
where
n
 (V )2  (V
ˆ   
i 1 

i
i 1 )
2
V1 
2
n
 yi and Vi   wh and y  y   yn 1 yn .
1 2

h i

TheconcentrationindexforthevariableTwhentherankingvariableisYisestimatedas
where ˆT istheaverageofvariableT,
ˆ
 T  1  T IC
ˆ T
n
 (V )2  (V
ˆT   
i 1 

i
i 1 )
2
V1 
2
 ti 

n
andwhere Vi   wh and y  y   yn 1 yn .
1 2
h i





Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimateinequality,forinstancebyusingsimultaneouslypercapitaconsumptionandper
capitaincome.
Toestimateaconcentrationindex,theusermustselectarankingvariable..
Agroupvariablecanbeusedtoestimateinequalityatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.9
13.2
DifferencebetweenGini/concentrationindices(digini)
ThismoduleestimatesdifferencesbetweentheGini/concentrationindicesoftwodistributions.
Foreachofthetwodistributions:
 Onevariableofinterestshouldbeselected;
 Toestimateaconcentrationindex,arankingvariablemustbeselected;
 Conditionscanbespecifiedtofocusonspecificpopulationsubgroups;
28


Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
13.3
Generalisedentropyindex(ientropy)
Thegeneralizedentropyindexisestimatedas

 y   

1

 w i  i   1 if   0,1
 ˆ

   1 n w i
 

 i
 
i 1

 1
 ˆ 
Î     
w i log  
if   0 
n
y
i
i


w
 i 1 i

y 
wy
 1
if   1
 i i log  i 
 n
ˆ
ˆ 

i
  wi
 i 1




Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimateinequalitysimultaneouslyforpercapitaconsumptionandforpercapitaincome.
Agroupvariablecanbeusedtoestimateinequalityatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
13.4
Differencebetweengeneralizedentropyindices(diengtropy)
Thismoduleestimatesdifferencesbetweenthegeneralizedentropyindicesoftwodistributions.
Foreachofthetwodistributions:




Onevariableofinterestshouldbeselected;
Conditionscanbespecifiedtofocusonspecificpopulationsubgroups;
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
29
13.5
Atkinsonindex(iatkinson)
DenotetheAtkinsonindexofinequalityforthegroupkby I(ε) .Itcanbeexpressedasfollows:
n
 w i yi
ˆ
ˆI(ε)  ˆ  () where ˆ  i 1
n
ˆ
 wi
TheAtkinsonindexofsocialwelfareisasfollows:




i 1
1

 1


 1 n

 if   1 and   0
w i (yi )1 ε 


 n
i
1


  wi

  i 1
ξ̂(ε)  






n

1

ε  1
Exp
w
ln(y
)

i
i 

n


i
1


  wi


 i 1


Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimateinequalitysimultaneouslyforpercapitaconsumptionandforpercapitaincome.
Agroupvariablecanbeusedtoestimateinequalityatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
13.6
DifferencebetweenAtkinsonindices(diatkinson)
ThismoduleestimatesdifferencesbetweentheAtkinsonindicesoftwodistributions.
Foreachofthetwodistributions:
 Onevariableofinterestshouldbeselected;
 Conditionscanbespecifiedtofocusonspecificpopulationsubgroups;
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
30
13.7
Coefficientofvariationindex(icvar)
Denote the coefficient of variation index of inequality for the group k by CV. It can be expressed as
follows:
1
n
 n
2
2
w
y
/
w i  ˆ 2 


i i

i 1
   i 1

CV


ˆ 2








Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimateinequalitysimultaneouslyforpercapitaconsumptionandforpercapitaincome.
Agroupvariablecanbeusedtoestimateinequalityatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
13.8
Differencebetweencoefficientofvariation(dicvar)
Thismoduleestimatesdifferencesbetweencoefficient of variation indicesoftwodistributions.
Foreachofthetwodistributions:
 Onevariableofinterestshouldbeselected;
 Conditionscanbespecifiedtofocusonspecificpopulationsubgroups;
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
13.9
Quantile/shareratioindicesofinequality(inineq)
Thequantileratioisestimatedas
 , p )  Q̂(p1 )
QR(p
1 2
Q̂(p 2 )
where Q(p) denotesap‐quantileand p1 and p 2 arepercentiles.
Theshareratioisestimatedas


GL(p2)-GL(p1)

SR(p1,p2,p3,p4)



GL(p4)-GL(p3)
31
where GL(p) istheGeneralisedLorenzcurveand p1 , p 2 , p3 and p 4 arepercentiles.
 Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimateinequalitysimultaneouslyforpercapitaconsumptionandforpercapitaincome.
 Agroupvariablecanbeusedtoestimateinequalityatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
13.10 DifferencebetweenQuantile/Shareindices(dinineq)
ThismoduleestimatesdifferencesbetweentheQuantile/Shareindicesoftwodistributions.
Foreachofthetwodistributions:
 Onevariableofinterestshouldbeselected;
 Conditionscanbespecifiedtofocusonspecificpopulationsubgroups;
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged;
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
13.11 TheAraar(2009)multidimensionalinequalityindex
The Araar (2009) the multidimensional inequality index for the K dimensions of wellbeing takes
the following form:
K
I   k  k I k  1  k  Ck 
i 1
where k is the weight attributed to the dimension k (may take the same value across the
dimensions or can depend on the averages of the wellbeing dimensions). I k  Ck are respectively
the relative –absolute- Gini and concentration indices of component k . The normative parameter
k controls the sensitivity of the index to the inter-correlation between dimensions. For more
details, see:
Abdelkrim Araar, 2009. "The Hybrid Multidimensional Index of Inequality," Cahiers de recherche 0945,
CIRPEE: http://ideas.repec.org/p/lvl/lacicr/0945.html
14 DASPandpolarizationindices
14.1
TheDERindex(ipolder)
32
TheDuclos,EstebanandRay(2004)(DER)polarizationindexcanbeexpressedas:
DER()   f (x)1 f (y) y  x dydx wheref(x)denotesthedensityfunctionatx.Thediscreteformulathatisusedtoestimatethisindex
isasfollows:
n

 w i f (yi ) a(yi )
DER()  i 1
n
 wi
i 1
ThenormalizedDERestimatedbythismoduleisdefinedas:
DER()
DER() 
2(1 )
where:
 i
  2  w j  wi
j1
a(yi )    yi  
N

 wi
 

i 1

   i 1

   2  w j y j  w i yi 
  1   j1

N
  

 wi
  

i 1
  

TheGaussiankernelestimatorisusedtoestimatethedensityfunction.
 Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimatepolarizationbyusingsimultaneouslypercapitaconsumptionandpercapita
income.
 Agroupvariablecanbeusedtoestimatepolarizationatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
Mainreference
DUCLOS,J.‐Y.,J.ESTEBAN,ANDD.RAY(2004):“Polarization:Concepts,Measurement,
Estimation,”Econometrica,72,1737–1772.
14.2
DifferencebetweenDERpolarizationindices(dipolder)
ThismoduleestimatesdifferencesbetweentheDERindicesoftwodistributions.
Foreachofthetwodistributions:
 Onevariableofinterestshouldbeselected;
 Conditionscanbespecifiedsuchastofocusonspecificpopulationsubgroups;
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
33
Theresultsaredisplayedwith6decimals;thiscanbechanged.

14.3
TheFosterandWolfson(1992)polarizationindex(ipolfw)
TheFosterandWolfson(1992)polarizationindexcanbeexpressedas:

FW  2  2  0.5  Lorenz(p  0.5)  Gini 
median




Theusercanselectmorethanonevariableofinterestsimultaneously.Forexample,onecan
estimatepolarizationbyusingsimultaneouslypercapitaconsumptionandpercapita
income.
Agroupvariablecanbeusedtoestimatepolarizationatthelevelofacategoricalgroup.Ifa
groupvariableisselected,onlythefirstvariableofinterestisthenused.
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
Mainreference
FOSTER,J.ANDM.WOLFSON(1992):“PolarizationandtheDeclineoftheMiddleClass:Canadaand
theU.S.”mimeo,VanderbiltUniversity.
14.4
DifferencebetweenFosterandWolfson(1992)polarizationindices
(dipolfw)
ThismoduleestimatesdifferencesbetweentheFWindicesoftwodistributions.
Foreachofthetwodistributions:
 Onevariableofinterestshouldbeselected;
 Conditionscanbespecifiedsuchastofocusonspecificpopulationsubgroups;
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
 Theresultsaredisplayedwith6decimals;thiscanbechanged.
14.5
TheGeneralisedEsteban,GradinandRay(1999)polarisationindex
(ipoger)
The proposed measurement of polarisation by Esteban and Ray (1994) is defined as
follows:
34
P
ER
m m
(f , )   p1j p k  j   k j1 k 1
where  j and p j denote respectively the average income and the population share of
group j. The parameter   1,1.6 reflects sensitivity of society to polarisation. The first
stepfortheestimationrequirestodefineexhaustiveandmutuallyexclusivegroups,  .This
willinvolvesomedegreeoferror.Takingintoaccountthisidea,themeasureofpolarisation
proposedbyEstebanetal.(1999)isobtainedaftercorrectingthe P ER () indexappliedto
the simplified representation of the original distribution with a measure of the grouping
error.Nonetheless,whendealingwithpersonalorspatialincomedistributions,thereare
no unanimous criteria for establishing the precise demarcation between different groups.
Toaddressthisproblem,Estebanetal.(1999)followthemethodologyproposedbyAghevli
andMehran(1981)andDaviesandShorrocks(1989)inordertofindanoptimalpartition
ofthedistributionforagivennumberofgroups, * .Thismeansselectingthepartitionthat
 
minimises the Gini index value of within‐group inequality, Error  G  f   G * (see
Esteban et al., 1999). The measure of polarisation proposed by Esteban et al. (1999) is
thereforegivenby:

m m
 
P EGR (f , , * , )   p1j p k  j  k   G  f   G *
j1 k 1
where,   0 isaparameterthatinformsabouttheweightassignedtotheerrorterm.(In
thestudyofEstebanetal.(1999),thevalueusedis   1 ).
The Stata module ipoegr.ado estimates the generalised form of the Esteban et al. (1999)
polarisationindex.Inadditiontotheusualvariables,thisroutineoffersthethreefollowing
options:
1. The number of groups. Empirical studies use two or three groups. The user can select the
numberofgroups.Accordingtothisnumber,theprogramsearchesfortheoptimalincome
interval for each group and displays them. It also displays the error in percentage, ie:
  *100 ;
G  f   G *
G f 
2. Theparameter  ;
3. Theparameter  .
To respect the scale invariance principle, all incomes are divided by average income i.e.
 j   j /  .Inaddition,wedividetheindexbythescalar2tomakeitsintervalliebetween


0and1when   1 .
35
m m
P EGR (f , , * , )  0.5   p1j p k  j   k   G  f   G *
 j1 k 1


14.6

  

TheInaki(2008)polarisationindex(ipoger)
Letapopulationbesplitinto N groups,eachoneofsize ni  0 .Thedensityfunction,themeanand
thepopulationshareofgroup i aredenotedby fi ( x) , i and  i respectively.  istheoverallmean.
We therefore have that

fi ( x)  1 ,
N
  i i   and
i 1
N

i 1
i
 1 . Using Inaki (2008), a social
polarisationindexcanbedefinedas:
N
P ( F )    PW (i, F )  PB (i, F )  i 1
where
PW (i, F )    1 i2
 f
1
i
( x) f i ( y )  x  y  dydx and

PB (i, F )    1 i1      i i   fi

1
( x) dx  1   i   fi
1

( x) xdx 

ThemoduleStatadspolallowsperformingthedecompositionofthesocialpolarisationindex P( F ) intogroupcomponents.
 Theusercanselecttheparameteralpha;
 Theusercanselecttheuseofafasterapproachfortheestimationofthedensityfunction;
 Standarderrorsareprovidedforallestimatedindices.Theytakeintoaccountthefull
samplingdesign;
 Theresultsaredisplayedwith6decimalsbydefault;thiscanbechanged;
 TheusercansaveresultsinExcelformat.
Theresultsshow:
 Theestimatedpopulationshareofsubgroup i :  i ;

Theestimatedincomeshareofsubgroup i :  i i /  ;

Theestimated PW (i, F ) indexofsubgroup i ;

Theestimated PB (i, F ) indexofsubgroup i ;

Theestimated PW 
i
W

Theestimated PB
i
B

Theestimatedtotalindex PF  P (i, F ) index;
  P (i, F ) index;
36
Toopenthedialogboxformoduledspol,typedbdspolinthecommandwindow.
Example:
Forillustrativepurposes,weusea1996Cameroonianhouseholdsurvey,whichismadeof
approximately1700households.Thevariablesusedare:
Variables:
Stratuminwhichahouseholdlives
STRATA
Primarysamplingunitofthehousehold
PSU
WEIGHT Samplingweight
SIZE
Householdsize
INS_LEV
Educationleveloftheheadofthehousehold
1. Primary;
2. ProfessionalTraining,secondaryandsuperior;
3. Notresponding.
We decompose the above social polarization index using the module dspol by splitting the
Cameroonian population into three exclusive groups, according to the education level of the
householdhead.Wefirstinitializethesamplingdesignofthesurveywiththedialogboxsvysetas
showninwhatfollows:
37
Afterthat,openthedialogboxbytypingdbdspol,andchoosevariablesandparametersasin:
AfterclickingSUBMIT,thefollowingresultsappear:
Mainreferences
1.
2.
3.
DUCLOS,J.‐Y.,J.ESTEBAN,ANDD.RAY(2004):“Polarization:Concepts,Measurement,Estimation,”
Econometrica,72,1737–1772.
TianZ.&all(1999)"FastDensityEstimationUsingCF‐kernelforVeryLargeDatabases".
http://portal.acm.org/citation.cfm?id=312266
IñakiPermanyer,2008."TheMeasurementofSocialPolarizationinaMulti‐groupContext,"UFAE
andIAEWorkingPapers736.08,UnitatdeFonamentsdel'AnàlisiEconòmica(UAB)andInstitut
d'AnàlisiEconòmica(CSIC).
38
15 DASPanddecompositions
15.1
FGTPoverty:decompositionbypopulationsubgroups(dfgtg)
ThedgfgtmoduledecomposestheFGTpovertyindexbypopulationsubgroups.Thisdecomposition
takestheform
G
 ( z;  )    ( g ) P
 (z;  ; g ) P
g 1
where G isthenumberofpopulationsubgroups.Theresultsshow:

 ( z;  ; g ) TheestimatedFGTindexofsubgroup g : P

Theestimatedpopulationshareofsubgroup g :  ( g ) 

 ( z;  ; g ) Theestimatedabsolutecontributionofsubgroup g tototalpoverty:  ( g ) P
Theestimatedrelativecontributionofsubgroup g tototal


 ( z;  ; g ) / P
 ( z;  ) poverty:  ( g ) P
Anasymptoticstandarderrorisprovidedforeachofthesestatistics.
Toopenthedialogboxformoduledfgtg,typedbdfgtginthecommandwindow.
Figure8:DecompositionoftheFGTindexbygroups
NotethattheusercansaveresultsinExcelformat.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.7
39
15.2 FGTPoverty:decompositionbyincomecomponentsusingtheShapley
value(dfgts)
The dfgts module decomposes the total alleviation of FGT poverty into a sum of the contributions
generated by separate income components. Total alleviation is maximal when all individuals have an
income greater than or equal to the poverty line. A negative sign on a decomposition term indicates that
an income component reduces poverty. Assume that there exist K income sources and that sk denotes
income source
k . The FGT index is defined as:
n

y
 wi 1  z
K
  z;  ; y   s   i 1
P

k
k 1 




n
 wi
i 1
where wi is the weight assigned to individual i and n is sample size. The dfgts Stata module estimates:



The share in total income of each income source
k;
  1 );
k to the value of ( P
  1 );
The relative contribution of each source k to the value of ( P
The absolute contribution of each source
Note that the dfgts ado file requires the module shapar.ado, which is programmed to perform
decompositions using the Shapley value algorithm developed by Araar and Duclos (2008).

Araar A and Duclos J‐Y (2008), “An algorithm for computing the Shapley Value”, PEP and CIRPEE. Tech.‐
Note: Novembre‐2008: http://dad.ecn.ulaval.ca/pdf_files/shap_dec_aj.pdf Empirical illustration with a Nigerian household survey
We use a survey of Nigerian households (NLSS, using 17764 observations) carried out between
September 2003 and August 2004 to illustrate the use of the dfgts module. We use per capita total
household income as a measure of individual living standards. Household observations are weighted by
household size and sampling weights to assess poverty over all individuals. The six main income
components are:






source_1: Employment income;
source_2: Agricultural income;
source_3: Fish-processing income;
source_4: Non-farm business income;
source_5: Remittances received;
source_6: All other income;
The Stata data file is saved after initializing its sampling design with the command svyset.

To open the dialog box for module dfgts, type db dfgts in the command window.
40
Figure 1: Decomposition of the FGT index by income components





Indicate the varlist of the six income sources.
Indicate that the poverty line is set to 15 000 $N.
Set the variable HOUSEHOLD SIZE.
Set the variable HOUSEHOLD WEIGHT.
Click on the button SUBMIT. The following results appear:
41
15.3
AlkireandFoster(2011)MDindexofpoverty:decompositionby
populationsubgroups(dmdafg)
ThedmdafgmoduledecomposestheMDAlkireandFosterindexofpovertyindexbypopulation
subgroups.Thisdecompositiontakestheform.Theresultsshow:
 TheestimatedAlkireandFosterindexofeachsubgroup:
 Theestimatedpopulationshareofsubgroup;
 Theestimatedabsolutecontributionofsubgroup g tototalpoverty;
 Theestimatedrelativecontributionofsubgroup g tototalpoverty;
Anasymptoticstandarderrorisprovidedforeachofthesestatistics.
15.4
AlkireandFoster(2011:decompositionbydimensionsusingthe
Shapleyvalue(dmdafs)
The dmdafs module decomposes the Alkire and Foster (2011) multidimensional poverty
indices into a sum of the contributions generated by each of the poverty dimensions. It uses the
Shapley characteristic function. The non‐presence of a given factor –dimension‐ is obtained by
settingthelevelofthatdimensiontoitsspecificpovertyline,thusensuringthenon‐contributionof
this dimension to the AF (2011) indices. Note that the dmdafs ado file requires the module
shapar.ado, which is programmed to perform decompositions using the Shapley value algorithm
developedbyAraarandDuclos(2008).
 Araar A and Duclos J‐Y (2008), “An algorithm for computing the Shapley Value”, PEP and
CIRPEE.Tech.‐Note:Novembre‐2008:http://dad.ecn.ulaval.ca/pdf_files/shap_dec_aj.pdf
42
15.5
FGTPoverty:decompositionbyincomecomponentsusingthe
Shapleyvalue(dfgts)
The dfgts module decomposes the total alleviation of FGT poverty into a sum of the
contributions generated by separate income components. Total alleviation is maximal when all
individuals have an income greater than or equal to the poverty line. A negative sign on a
decompositiontermindicatesthatanincomecomponentreducespoverty.Assumethatthereexist
K incomesourcesandthat sk denotesincomesource k . TheFGTindexisdefinedas:
n

y
 wi 1  z
K
  z;  ; y   s   i 1
P

k
k 1 




n
 wi
i 1
where wi istheweightassignedtoindividual i and n issamplesize.ThedfgtsStatamodule
estimates:
 Theshareintotalincomeofeachincomesource k ;

  1 );
Theabsolutecontributionofeachsource k tothevalueof( P

  1 );
Therelativecontributionofeachsource k tothevalueof( P
Notethatthedfgtsadofilerequiresthemoduleshapar.ado,whichisprogrammedtoperform
decompositionsusingtheShapleyvaluealgorithmdevelopedbyAraarandDuclos(2008).
 Araar A and Duclos J‐Y (2008), “An algorithm for computing the Shapley Value”, PEP and
CIRPEE.Tech.‐Note:Novembre‐2008:http://dad.ecn.ulaval.ca/pdf_files/shap_dec_aj.pdf
EmpiricalillustrationwithaNigerianhouseholdsurvey
We use a survey of Nigerian households (NLSS, using 17764 observations) carried out between
September2003andAugust2004toillustratetheuseofthedfgtsmodule.Weusepercapitatotal
household income as a measure of individual living standards. Household observations are
weighted by household size and sampling weights to assess poverty over all individuals. The six
mainincomecomponentsare:
 source_1:Employmentincome;
 source_2:Agriculturalincome;
 source_3:Fish‐processingincome;
 source_4:Non‐farmbusinessincome;
 source_5:Remittancesreceived;
 source_6:Allotherincome;
43
TheStatadatafileissavedafterinitializingitssamplingdesignwiththecommandsvyset.Toopen
thedialogboxformoduledfgts,typedbdfgtsinthecommandwindow.
Figure9:DecompositionofFGTbyincomecomponents





Indicatethevarlistofthesixincomesources.
Indicatethatthepovertylineissetto15000$N.
SetthevariableHOUSEHOLDSIZE.
SetthevariableHOUSEHOLDWEIGHT.
ClickonthebuttonSUBMIT.Thefollowingresultsappear:
44
15.6
DecompositionofthevariationinFGTindicesintogrowthand
redistributioncomponents(dfgtgr)
DattandRavallion(1992)decomposethechangeintheFGTindexbetweentwoperiods,t1andt2,
intogrowthandredistributioncomponentsasfollows:
P2  P1   P( t2 ,  t1 )  P( t1 ,  t1 )    P( t1 ,  t2 )  P( t1 ,  t1 )   R / ref  1
  


var iation
C1
C2
P2  P1   P( t2 ,  t2 )  P( t1 ,  t2 )    P( t2 ,  t2 )  P( t2 ,  t1 )   R
  
var iation
where
variation
C1
C2
R
Ref
C1
C2
=differenceinpovertybetweent1andt2;
=growthcomponent;
=redistributioncomponent;
=residual;
=periodofreference.
P (  t1 ,  t1 ) :theFGTindexofthefirstperiod
P (  t1 ,  t1 ) :theFGTindexofthesecondperiod
45
/ ref  2 P( t 2 ,  t1 ) :theFGTindexofthefirstperiodwhenallincomes y it1 ofthefirstperiodaremultiplied
by  t 2 /  t1 P( t1 ,  t 2 ) :theFGTindexofthesecondperiodwhenallincomes y it 2 ofthesecondperiodare
multipliedby  t1 /  t 2 TheShapleyvaluedecomposesthevariationintheFGTIndexbetweentwoperiods,t1andt2,into
growthandredistributioncomponentsasfollows:
P2  P1  C1  C 2



Variation




1
P ( t 2 ,  t1 )  P ( t1 ,  t1 )  P ( t 2 ,  t 2 )  P ( t1 ,  t 2 )
2
1
t1 t 2
t1 t1
t2 t2
t 2 t1
C 2  P ( ,  )  P ( ,  )  P ( ,  )  P (  ,  )
2
C1 
15.7
DecompositionofchangeinFGTpovertybypovertyandpopulation
groupcomponents–sectoraldecomposition‐(dfgtg2d).
Additive poverty measures, like the FGT indices, can be expressed as a sum of the
poverty contributions of the various subgroups of population. Each subgroup contributes
byitspopulationshareandpovertylevel.Thus,thechangeinpovertyacrosstimedepends
onthechangeinthesetwocomponents.Denotingthepopulationshareofgroup inperiod
by
, the change in poverty between two periods can be expressed as (see Huppi
(1991)andDuclosandAraar(2006)):
(06)
This decomposition use the initial period as the one. If the reference period is the
final,thedecompositiontakestheform:
46
(06)
Toremovethearbitrarnessinselectingthereferenceperiod,wecanusetheShapley
decompositionapproach,finding:
(07)
where
is
the
average
population share
and
.TheDASPmoduledfgtg2dperformsthissectoral
decomposition,andthisbyselectingthereferenceperiodoftheShapleyapproach(seethe
followingdialogbox):
47
Figure 10: Sectoral decomposition of FGT
. dfgtg2d exppc exppcz, alpha(0) hgroup(gse) pline(41099) file1(C:\data\bkf94I.dta) hsize1(size) file2(C:\data\bkf98I.dta) hsize2(size) ref(0)
Decomposition of the FGT index by groups
Group variable : gse
Parameter alpha : 0.00
Population shares and FGT indices
Group
Wage-earner (public sector)
Wage-earner (private sector)
Artisan or trader
Other type of earner
Crop farmer
Subsistence farmer
Inactive
Population
Initial
Pop. share
Initial
FGT index
Final
Pop. share
Wage-earner (public sector)
Wage-earner (private sector)
Artisan or trader
Other type of earner
Crop farmer
Subsistence farmer
Inactive
Population
Difference in
FGT index
0.042971
0.003790
0.026598
0.002164
0.062640
0.004288
0.006650
0.001308
0.104402
0.014896
0.680885
0.016403
0.075856
0.004839
0.022406
0.012599
0.067271
0.024093
0.097548
0.014712
0.194481
0.060817
0.500707
0.034911
0.514999
0.021132
0.414986
0.035336
0.041403
0.003927
0.029035
0.002624
0.055795
0.004666
0.005689
0.000923
0.167806
0.014125
0.653552
0.015083
0.046719
0.003354
0.059094
0.023396
0.111283
0.023087
0.126776
0.018202
0.293404
0.089680
0.424391
0.024457
0.533956
0.011572
0.386852
0.032340
0.036688
0.026573
0.044012
0.033369
0.029228
0.023404
0.098923
0.108357
-0.076316
0.042625
0.018957
0.024093
-0.028134
0.047901
1.000000
0.000000
0.444565
0.016124
1.000000
0.000000
0.452677
0.010927
0.008113
0.019477
Decomposition components
Group
Final
FGT index
Poverty
Component
Population
Component
Interaction
Component
0.001548
0.001117
0.001224
0.000930
0.001731
0.001380
0.000610
0.000700
-0.010387
0.005992
0.012648
0.016127
-0.001724
0.002932
-0.000064
0.001931
0.000218
0.001222
-0.000768
0.002417
-0.000234
0.000930
0.029328
0.013963
-0.014336
0.018726
-0.011681
0.004317
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.005650
===
0.002463
===
0.000000
===
48
15.8
DecompositionofFGTpovertybytransientandchronicpoverty
components(dtcpov)
Thisdecomposestotalpovertyacrosstimeintotransientandchroniccomponents.
TheJalanandRavallion(1998)approach
Let yit betheincomeofindividualiinperiodtand i beaverageincomeovertheTperiodsforthat
sameindividuali,i=1,…,N.Totalpovertyisdefinedas:
T N
t 
  w i (z  yi ) 
TP(, z)  t 1i 1
N
T  wi
i 1
Thechronicpovertycomponentisthendefinedas:
N

 w i (z  i )
CPC(, z)  i 1
N
 wi
i 1
Transientpovertyequals:
TPC(, z)  TP(, z)  CPC(, z) Duclos,AraarandGiles(2006)approach
Let yit be the income of individual i in period t and i be average income over the T periods for
individuali.Let (, z) bethe”equally‐distributed‐equivalent”(EDE)povertygapsuchthat:
1/ 
(, z)   TP(, z) 
Transientpovertyisthendefinedas
N
 w i i (, z)
TPC(, z)  i 1
N
 wi
i 1
1/ 
 T
 
where i   i  , z    i 1, z  andB  i (, z)     (z  yit )
  / T
 
  it
49
andchronicpovertyisgivenby
CPC(, z)  (, z)  TPC(, z) Notethatthenumberofperiodsavailableforthistypeofexerciseisgenerallysmall.Becauseofthis,
abias‐correctionistypicallyuseful,usingeitherananalytical/asymptoticorbootstrapapproach.
Toopenthedialogboxformoduledtcpov,typedbdtcpovinthecommandwindow.
Figure11:Decompositionofpovertyintotransientandchroniccomponents





Theusercanselectmorethanonevariableofinterestsimultaneously,whereeachvariable
representsincomeforoneperiod.
Theusercanselectoneofthetwoapproachespresentedabove.
Small‐T‐bias‐correctionscanbeapplied,usingeitherananalytical/asymptoticora
bootstrapapproach.
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
References
JalanJyotsna,andMartinRavallion.(1998)"TransientPovertyinPostreformRuralChina"Journalof
ComparativeEconomics,26(2),pp.338:57.
Jean‐Yves Duclos & Abdelkrim Araar & John Giles, 2006. "Chronic and Transient Poverty:
MeasurementandEstimation,withEvidencefromChina,"WorkingPaper0611,CIRPEE.
50
15.9
Inequality:decompositionbyincomesources(diginis)
Analyticalapproach
Thediginismoduledecomposesthe(usual)relativeortheabsoluteGiniindexbyincomesources.
Thethreeavailableapproachesare:
 Rao’sapproach(1969)
 LermanandYitzhaki’sapproach(1985)
 Araar’sapproach(2006)
Reference(s)
 Lerman, R. I., and S. Yitzhaki. "Income Inequality Effects by Income Source: A New
Approach and Applications to the United States." Review of Economics and Statistics 67
(1985):151‐56.
 AraarAbdelkrim(2006).OntheDecompositionoftheGiniCoefficient:anExactApproach,
withanIllustrationUsingCameroonianData,Workingpaper02‐06,CIRPEE.
Shapleyapproach
The dsineqs module decomposes inequality indices into a sum of the contributions generated by
separateincomecomponents.ThedsineqsStatamoduleestimates:
 Theshareintotalincomeofeachincomesource k ;
 Theabsolutecontributionofeachsource k totheGiniindex;
 Therelativecontributionofeachsource k totheGiniindex;
For the Shapley decomposition, the rule that is used to estimate the inequality index for a
subset of components is by suppressing the inequality generated by the complement subset of
components. For this, we generate a counterfactual vector of income that equals the sum of the
componentsofthesubsetplustheaverageofthecomplementsubset.Notethatthedsineqsado
file requires the module shapar.ado, which is programmed to perform decompositions using the
ShapleyvaluealgorithmdevelopedbyAraarandDuclos(2008).

Araar A and Duclos J‐Y (2008), “An algorithm for computing the Shapley Value”, PEP and
CIRPEE.Tech.‐Note:Novembre‐2008::http://dad.ecn.ulaval.ca/pdf_files/shap_dec_aj.pdf
To open the dialog box for module dsginis, type db dsginis in the command window.
51
Figure 12: Decomposition of the Gini index by income sources (Shapley approach)
15.10 Regression‐baseddecompositionofinequalitybyincomesources
A useful approach to show the contribution of income covariates to total inequality is by
decomposingthelatterbythepredictedcontributionsofcovariates.Formally,denotetotalincome
by y andthesetofcovariatesby X  x1, x2 , , xK .Usingalinearmodelspecification,wehave:


y  ˆ0  ˆ1 x1  ˆ2 x2    ˆk xk    ˆK xK  ˆ where ̂ 0 and ˆ denoterespectivelytheestimatedconstanttermandtheresidual.
Twoapproachesforthedecompositionoftotalinequalitybyincomesourcesareused:
1‐ The Shapley approach: This approach is based on the expected marginal contribution of
incomesourcestototalinequality.
2‐ The Analytical approach: This approach is based on algebraic developments that express
totalinequalityasasumofinequalitycontributionsofincomesources.
WiththeShapleyapproach:
 Theusercanselectamongthefollowingrelativeinequalityindices;
 Giniindex
 Atkinsonindex
 Generalizedentropyindex
 Coefficientvariationindex
 Theusercanselectamongthefollowingmodelspecifications;

Linear: y  ˆ0  ˆ1 x1  ˆ2 x2    ˆK xK  ˆ 
SemiLogLinear: log( y )  ˆ0  ˆ1 x1  ˆ2 x2    ˆK xK  ˆ 52
WiththeAnalyticalapproach:
 Theusercanselectamongthefollowingrelativeinequalityindices;
 Giniindex
 Squaredcoefficientvariationindex
 Themodelspecificationislinear.
Decomposingtotalinequalitywiththeanalyticalapproach:
Total income equals y  s0  s1  s2    sK  sR where s0 is the estimated constant, sk  ˆk X k and sR is the estimated residual. As reported by Wang 2004, relative inequality indices are not
defined when the average of the variable of interest equals zero (the case of the residual). Also,
inequalityindicesequalzerowhenthevariableofinterestisaconstant(thecaseoftheestimated
constant).Todealwiththesetwoproblems,Wang(2004)proposesthefollowingbasicrules:
Let yˆ  s0  s1  s2    sK and y  s1  s2    sK ,then: I ( y )  cs0  I ( y )  csr Thecontributionoftheconstant: cs0  I ( y )  I ( yˆ ) Thecontributionoftheresidual: csR  I ( yˆ )  I ( y ) TheGiniindex:
UsingRao1969’sapproach,therelativeGiniindexcanbedecomposedasfollows:
I ( y ) 
k 
C  y k
where  y istheaverageof y and C k isthecoefficientofconcentrationof sk when y istheranking
variable.
TheSquaredcoefficientofvariationindex:
AsshownbyShorrocks1982,thesquaredcoefficientofvariationindexcanbedecomposedas:
K
I ( y )  
C ov( y , sk )
k 1
 y2
Shapleydecompositions:
TheShapleyapproachisbuiltaroundtheexpectedmarginalcontributionofacomponent.Theuser
canselectamongtwomethodstodefinetheimpactofmissingagivencomponent.
 Withoption:method(mean),whenacomponentismissingfromagivensetofcomponents,
itisreplacedbyitsmean.
 Withoption:method(zero),whenacomponentismissingfromagivensetofcomponents,it
isreplacedbyzero.
Asindicatedabove,wecannotestimaterelativeinequalityfortheresidualcomponent.
53

Forthelinearmodel,thedecompositiontakesthefollowingform: I ( y )  I ( yˆ )  csr ,where
thecontributionoftheresidualis csr  I ( y )  I ( yˆ ) .

FortheSemi‐loglinearmodel,theShapleydecompositionisappliedtoallcomponents
includingtheconstantandtheresidual.
WiththeShapleyapproach,theusercanusetheloglinearspecification.However,theusermust
indicatetheincomevariableandnotthelogofthatvariable(DASPautomaticallyrunsthe
regressionwithlog(y)asthedependentvariable).
Example1
54
55
56
Example2
Withthisspecification,wehave y  E xp( s0  s1  s2    sK  sR ) .Then:

Wecannotestimatetheincomeshare(nolinearform);
57

K
 E xp( s ).E xp( s
Thecontributionoftheconstantisnil. y  E xp( s0 ).
k 1
k
E
) .Addinga
constantwillhavenotanyimpact.
Example3
15.11 Giniindex:decompositionbypopulationsubgroups(diginig).
The diginig module decomposes the (usual) relative or the absolute Gini index by population
subgroups. Let there be G population subgroups. We wish to determine the contribution of every
oneofthosesubgroupstototalpopulationinequality.TheGiniindexcanbedecomposedasfollows:
G
I   g g Ig  I  R

g 1


 Within Overlap Between
where
58
g
g
I
R
thepopulationshareofgroupg;
theincomeshareofgroupg.
between‐groupinequality(wheneachindividualisassignedtheaverageincome
ofhisgroup).
Theresidueimpliedbygroupincomeoverlap
15.12 Generalizedentropyindicesofinequality:decompositionby
populationsubgroups(dentropyg).
TheGeneralisedEntropyindicesofinequalitycanbedecomposedasfollows:

K
ˆI()   ˆ (k)  ˆ (k)  .I(k;
ˆ )  I()  ˆ 
  
k 1
where:
B ( k ) B ( k ) istheproportionofthepopulationfoundinsubgroupk.
isthemeanincomeofgroupk.
isinequalitywithingroupk.
B Ik;  is population inequality if each individual in subgroup k is given the mean
B I incomeofsubgroupk, (k) .
15.13 Polarization:decompositionoftheDERindexbypopulationgroups
(dpolag)
As proposed by Araar (2008), the Duclos, Esteban and Ray index can be decomposed as
follows:
P    1g 1g Rg Pg  
P  Between
g

Within
where
Rg 

a
g
( x) g ( x) f ( x)1 dx
 g  ag ( x) f g ( x)
1

dx
 g and g arerespectivelythepopulationandincomesharesofgroup g .
59
 g ( x) denotesthelocalproportionofindividualsbelongingtogroup g andhaving

income x ;
 P istheDERpolarizationindexwhenthewithin‐grouppolarizationorinequalityis
ignored;
 ThedpolasmoduledecomposestheDERindexbypopulationsubgroups.
Reference(s)
Abdelkrim Araar, 2008. "On the Decomposition of Polarization Indices: Illustrations
with Chinese and Nigerian Household Surveys," Cahiers de recherche 0806, CIRPEE.
15.14 Polarization:decompositionoftheDERindexbyincomesources
(dpolas)
As proposed by Araar (2008), the Duclos, Esteban and Ray index can be decomposed as
follows:
P    k CPk
k
 f ( x)

1
where CPk
ak ( x)dx
 k k 1

and k arerespectivelythepseudoconcentrationindexand
incomeshareofincomesource k .ThedpolasmoduledecomposestheDERindexbyincome
sources.
Reference(s)
Abdelkrim Araar, 2008. "On the Decomposition of Polarization Indices: Illustrations
with Chinese and Nigerian Household Surveys," Cahiers de recherche 0806, CIRPEE.
16 DASPandcurves.
16.1
FGTCURVES(cfgt).
FGTcurvesareusefuldistributivetoolsthatcaninteraliabeusedto:
1. Showhowthelevelofpovertyvarieswithdifferentpovertylines;
2. Testforpovertydominancebetweentwodistributions;
60
3. Testpro‐poorgrowthconditions.
FGTcurvesarealsocalledprimaldominancecurves.Thecfgtmoduledrawssuchcurveseasily.The
modulecan:
 drawmorethanoneFGTcurvesimultaneouslywhenevermorethanonevariableofinterest
isselected;
 drawFGTcurvesfordifferentpopulationsubgroupswheneveragroupvariableisselected;
 drawFGTcurvesthatarenotnormalizedbythepovertylines;
 drawdifferencesbetweenFGTcurves;
 listorsavethecoordinatesofthecurves;
 savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
 Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.
Toopenthedialogboxofthemodulecfgt,typethecommanddbdfgtinthecommandwindow.
Figure13:FGTcurves
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.4.
61
FGTCURVEwithconfidenceinterval(cfgts).
ThecfgtsmoduledrawsanFGTcurveanditsconfidenceintervalbytakingintoaccountsampling
design.Themodulecan:
 drawanFGTcurveandtwo‐sided,lower‐boundedorupper‐boundedconfidenceintervals
aroundthatcurve;
 conditiontheestimationonapopulationsubgroup;
 drawaFGTcurvethatisnotnormalizedbythepovertylines;
 listorsavethecoordinatesofthecurveandofitsconfidenceinterval;
 savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
 Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.5.
16.3
DifferencebetweenFGTCURVESwithconfidenceinterval(cfgts2d).
Thecfgts2dmoduledrawsdifferencesbetweenFGTcurvesandtheirassociatedconfidenceinterval
bytakingintoaccountsamplingdesign.Themodulecan:
 drawdifferencesbetweenFGTcurvesandtwo‐sided,lower‐boundedorupper‐bounded
confidenceintervalsaroundthesedifferences;
 normalizeornottheFGTcurvesbythepovertylines;
 listorsavethecoordinatesofthedifferencesbetweenthecurvesaswellastheconfidence
intervals;
 savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
 Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.5.
LorenzandconcentrationCURVES(clorenz).
Lorenzandconcentrationcurvesareusefuldistributivetoolsthatcaninteraliabeusedto:
1. showthelevelofinequality;
2. testforinequalitydominancebetweentwodistributions;
3. testforwelfaredominancebetweentwodistributions;
4. testforprogressivity.
TheclorenzmoduledrawsLorenzandconcentrationcurvessimultaneously.Themodulecan:
62







drawmorethanoneLorenzorconcentrationcurvesimultaneouslywhenevermorethan
onevariableofinterestisselected;
drawmorethanonegeneralizedorabsoluteLorenzorconcentrationcurvesimultaneously
whenevermorethanonevariableofinterestisselected;
drawmorethanonedeficitsharecurve;
drawLorenzandconcentrationcurvesfordifferentpopulationsubgroupswheneveragroup
variableisselected;
drawdifferencesbetweenLorenzandconcentrationcurves;
listorsavethecoordinatesofthecurves;
savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.

Toopenthedialogboxofthemoduleclorenz,typethecommanddbclorenzinthecommand
window.
Figure14:Lorenzandconcentrationcurves
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.8.
16.5
Lorenz/concentrationcurveswithconfidenceintervals(clorenzs).
TheclorenzsmoduledrawsaLorenz/concentrationcurveanditsconfidenceintervalbytaking
samplingdesignintoaccount.Themodulecan:
63






drawaLorenz/concentrationcurveandtwo‐sided,lower‐boundedorupper‐bounded
confidenceintervals;
conditiontheestimationonapopulationsubgroup;
drawLorenz/concentrationcurvesandgeneralizedLorenz/concentrationcurves;
listorsavethecoordinatesofthecurvesandtheirconfidenceinterval;
savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.
16.6
DifferencesbetweenLorenz/concentrationcurveswithconfidence
interval(clorenzs2d)
Theclorenz2dmoduledrawsdifferencesbetweenLorenz/concentrationcurvesandtheir
associatedconfidenceintervalsbytakingsamplingdesignintoaccount.Themodulecan:
 drawdifferencesbetweenLorenz/concentrationcurvesandassociatedtwo‐sided,lower‐
boundedorupper‐boundedconfidenceintervals;
 listorsavethecoordinatesofthedifferencesandtheirconfidenceintervals;
 savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
 Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.
16.7
Povertycurves(cpoverty)
Thecpovertymoduledrawsthepovertygaporthecumulativepovertygapcurves.
o Thepovertygapatapercentile p is: G ( p; z )  ( z  Q( p ))  o
Thecumulativepovertygapatapercentile p ,notedby CPG ( p; z ) ,isgivenby:
n
 wi ( z  yi )  I ( yi  Q( p ))
CPG ( p; z )  i 1
n
 wi
i 1
Themodulecanthus:
 drawmorethanonepovertygaporcumulativepovertygapcurvessimultaneously
whenevermorethanonevariableofinterestisselected;
 drawpovertygaporcumulativepovertygapcurvesfordifferentpopulationsubgroups
wheneveragroupvariableisselected;
64




drawdifferencesbetweenpovertygaporcumulativepovertygapcurves;
listorsavethecoordinatesofthecurves;
savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.
16.8
Consumptiondominancecurves(cdomc)
Consumption dominance curves are useful tools for studying the impact of indirect tax fiscal reforms on
poverty. The jth Commodity or Component dominance (C-Dominance for short) curve is defined as
follows:
 n
s 2 j
  wi ( z  yi )  yi
 i 1
n

wi



i 1
j
CD ( z , s )  
n
j

 wi K ( z  yi ) yi

j
i 1
 E  y | y  z  f ( z ) 
n

 wi

i 1
if s  2
if s  1
where K( ) is a kernel function and yj is the jth commodity. Dominance of order s is checked by
setting   s  1 . Thecdomcmoduledrawssuchcurveseasily.Themodulecan:
 drawmorethanoneCDcurvesimultaneouslywhenevermorethanonecomponentis
selected;
 drawtheCDcurveswithconfidenceintervals;
 estimatetheimpactofchangeinpriceofagivencomponentonFGTindex(CDcurve)fora
specifiedpovertyline;
 drawthenormalizedCDcurvesbytheaverageofthecomponent;
 listorsavethecoordinatesofthecurves;
 savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
 Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.
Toopenthedialogboxofthemodulecdomc,typethecommanddbcdomcinthecommandwindow.
65
Figure15:Consumptiondominancecurves
16.9
Difference/Ratiobetweenconsumptiondominancecurves
(cdomc2d)
Thecdomc2dmoduledrawsdifferenceorratiobetweenconsumptiondominancecurvesandtheir
associatedconfidenceintervalsbytakingsamplingdesignintoaccount.Themodulecan:
 drawdifferencesbetweenconsumptiondominancecurvesandassociatedtwo‐sided,lower‐
boundedorupper‐boundedconfidenceintervals;
 listorsavethecoordinatesofthedifferencesandtheirconfidenceintervals;
 savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
 Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.
16.10 DASPandtheprogressivitycurves
16.10.1
Checkingtheprogressivityoftaxesortransfers
The module cprog allows checking whether taxes or transfers are progressive.
Let X be a gross income, T be a given tax and B be a given transfer.
The tax T is Tax Redistribution (TR) progressive if :
PR  p   L X  p   CT  p   0 p  0,1
66
The transfer B is Tax Redistribution (TR) progressive if :
PR  p   C B  p   L X  p   0 p  0,1
The tax T is Income Redistribution (IR) progressive if :
PR  p   C X T  p   L X  p   0 p  0,1
The transfer B is Income Redistribution (IR) progressive if :
PR  p   C X  B  p   L X  p   0 p  0,1
16.10.2
Checkingtheprogressivityoftransfervstax
The module cprogbt allows checking whether a given transfer is more progressive than a given
tax.
The transfer B is more Tax Redistribution (TR) progressive than a tax T if :
PR  p   C B  p   CT  p   2L X  p   0 p  0,1
The transfer B is more Income Redistribution (TR) progressive than a tax T if :
PR  p   C X  B  p  -C X T  p   0 p  0,1
17 Dominance
17.1
Povertydominance(dompov)

Distribution1dominatesdistribution2atordersovertherange z  , z 

ifonlyif:
P1 ( ;  )  P2 ( ;  )     z , z  for   s  1.


ThisinvolvescomparingstochasticdominancecurvesatordersorFGTcurveswith   s  1 .This
applicationestimatesthepointsatwhichthereisareversaloftherankingofthecurves.Said
differently,itprovidesthecrossingpointsofthedominancecurves,thatis,thevaluesof  and
P1 ( ;  ) forwhich P1 ( ;  )  P2 ( ;  ) when:
sign( P1 (   ;  )  P2 (   ;  ))  sign( P2 (   ;  )  P1 (   ;  )) forasmall .Thecrossing
points  canalsobereferredtoas“criticalpovertylines”.
Thedompovmodulecanbeusedtocheckforpovertydominanceandtocomputecriticalvalues.
ThismoduleismostlybasedonAraar(2006):
67
Araar,Abdelkrim,(2006),Poverty,InequalityandStochasticDominance,TheoryandPractice:
Illustration with Burkina Faso Surveys, Working Paper: 06‐34. CIRPEE, Department of
Economics,UniversitéLaval.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.6.
17.2
Inequalitydominance(domineq)
Distribution1inequality‐dominatesdistribution2atthesecondorderifandonlyif:
L1 ( p )  L2 ( p )  p   0,1 Themoduledomineqcanbeusedtocheckforsuchinequalitydominance.Itisbasedmainlyon
Araar(2006):
Araar,Abdelkrim,(2006),Poverty,InequalityandStochasticDominance,TheoryandPractice:
Illustration with Burkina Faso Surveys, Working Paper: 06‐34. CIRPEE, Department of
Economics,UniversitéLaval.
Intersectionsbetweencurvescanbeestimatedwiththismodule.Itcanalsousedtocheckfortax
andtransferprogressivitybycomparingLorenzandconcentrationcurves.
17.3
DASPandbi‐dimensionalpovertydominance(dombdpov)
Lettwodimensionsofwell‐beingbedenotedby k  1, 2 .Theintersectionbi‐dimensionalFGTindex
fordistribution D isestimatedas
n
 2 k
k  
 wi   ( z  yi ) k 

 D ( Z ; A )  i 1  k 1
P
n
 wi
i 1
where Z   z1 , z2  and A  1 ,  2  arevectorsofpovertylinesandparameters  respectively,
and x  max( x, 0) .
Distribution1dominatesdistribution2atorders  s1 , s2  overtherange  0, Z   ifandonlyif:


P1 ( Z ; A  s  1)  P2 ( Z ; A  s  1)  Z  0, z1    0, z2   andfor 1  s1  1,  2  s2  1 .
TheDASPdombdpovmodulecanbeusedtocheckforsuchdominance.
Foreachofthetwodistributions:
 Thetwovariablesofinterest(dimensions)shouldbeselected;
 Conditionscanbespecifiedtofocusonspecificpopulationsubgroups;
 Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
68



Surfacesshowingthedifference,thelowerboundandtheupperboundoftheconfidence
surfacesareplottedinteractivelywiththeGnuPlottool.
Coordinatescanbelisted.
CoordinatescanbesavedinStataorGnuPlot‐ASCIIformat.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.12.
18 Distributivetools
18.1
Quantilecurves(c_quantile)
Thequantileatapercentilepofacontinuouspopulationisgivenby:
Q ( p )  F 1 ( p ) where p  F ( y ) isthecumulativedistributionfunctionaty.
For a discrete distribution, let n observations of living standards be ordered such that
y1  y2    yi  yi 1    yn . If F ( yi )  p  F ( yi 1 ) , we define Q( p)  yi 1 . The normalised
quantileisdefinedas Q ( p )  Q ( p ) /  .
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.10.
18.2
Incomeshareandcumulativeincomesharebygroupquantiles
(quinsh)
Thismodulecanbeusedtoestimate theincomeshares,aswellas,thecumulativeincome
sharesbyquantilegroups.Theusercanindicatethenumberofgrouppartition.Forinstance,ifthe
number is five, the quintile income shares are provided. We can also plot the graph bar of the
estimatedincomeshares.
18.3
Densitycurves(cdensity)
TheGaussiankernelestimatorofadensityfunction f ( x ) isdefinedby

fˆ ( x)  i
wi Ki ( x)
n
w
i 1
and
Ki ( x) 
1
exp  0.5 i ( x)2  and
h 2
i ( x) 
x  xi
h
i
wherehisabandwidththatactsasa“smoothing”parameter.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.10.
Boundary bias correction:
A problem occurs with kernel estimation when a variable of interest is bounded. It may be for instance
that consumption is bounded between two bounds, a minimum and a maximum, and that we wish to
estimate its density “close” to these two bounds. If the true value of the density at these two bounds is
69
positive, usual kernel estimation of the density close to these two bounds will be biased. A similar
problem occurs with non-parametric regressions.
Renormalisation approach:
One way to alleviate these problems is to use a smooth “corrected” Kernel estimator, following a paper by
Peter Bearse, Jose Canals and Paul Rilstone. A boundary-corrected Kernel density estimator can then be
written as
f̂ (x) 
*
i w i K i (x)K i (x)
n
 wi
i 1
where
K i (x) 
1
h 2

exp  0.5  i ( x ) 2

and  i ( x ) 
x  xi
h
and where the scalar K *i ( x ) is defined as
K *i ( x )  ( x ) P( i ( x ))

P()  1 

s 1 

s  1! 
2

2!
1
B
x  max
x  min




, B
, l s  (1 0 0 0)
( x )  M l s    K ()P()P() d  l s : A 
A


h
h
1

min is the minimum bound, and max is the maximum one. h is the usual bandwidth. This correction
removes bias to order hs.
DASP offers four options, without correction, and with correction of order 1, 2 and 3.
Refs:
 Jones,M.C.1993,simplyboundarycorrectionforKerneldensityestimation.Statisticsand
Computing3:135‐146.
 Bearse,P.,Canals,J.andRilstone,P.EfficientSemiparametricEstimationofDuration
ModelsWithUnobservedHeterogeneity,EconometricTheory,23,2007,281–308
Reflection approach:
The reflection estimator approaches the boundary estimator by “reflecting” the data at the
boundaries:
f̂ (x) 
r
i w i K i (x)
n
 wi
i 1
 xX
 x  X  2 min   x  X  2 max 
K r (x)  K 
 K
K

h
h
 h 

 

Refs:
 CwikandMielniczuk(1993),Data‐dependentBandwidthChoiceforaGradeDensityKernel
Estimate.StatisticsandprobabilityLetters16:397‐405
70

18.4
Silverman,B.W.(1986),DensityforStatisticsandDataAnalysis.LondonChapmanandHall
(p30).
Non‐parametricregressioncurves(cnpe)
Non‐parametric regression is useful to show the link between two variables without specifying
beforehandafunctionalform.Itcanalsobeusedtoestimatethelocalderivativeofthefirstvariable
withrespecttothesecondwithouthavingtospecifythefunctionalformlinkingthem.Regressions
withthecnpemodulecanbeperformedwithoneofthefollowingtwoapproaches:
18.4.1 Nadaraya‐Watsonapproach
AGaussiankernelregressionofyonxisgivenby:
E  y x    ( y | x) 
i wi Ki ( x) yi
i wi Ki ( x)
Fromthis,thederivativeof  ( y | x ) withrespecttoxisgivenby
 dy   ( y | x )
E
x 
x
 dx 
18.4.2 Locallinearapproach
ThelocallinearapproachisbasedonalocalOLSestimationofthefollowingfunctionalform:
1
1
1
K i ( x) 2 yi   ( x) K i ( x) 2   ( x) K i ( x) 2 ( xi  x)  v
or,alternatively,of:
1
1
1
K i ( x) 2 yi   K i ( x) 2   K i ( x) 2 ( xi  x)  vi Estimatesarethengivenby:
 dy 
x   E  y x    , E 
 dx 
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.10.
18.5
DASPandjointdensityfunctions.
Themodulesjdensitycanbeusedtodrawajointdensitysurface.TheGaussiankernelestimatorof
thejointdensityfunction f ( x, y ) isdefinedas:
71
2 

2





x
x
y
y


1



i
i  
f̂ (x, y) 
 w i exp      
  
n


2
h
h
     x   y   
2h x h y  w i i 1



n
1
i 1
Withthismodule:
 Thetwovariablesofinterest(dimensions)shouldbeselected;
 specificpopulationsubgroupcanbeselected;
 surfacesshowingthejointdensityfunctionareplottedinteractivelywiththeGnuPlottool;
 coordinatescanbelisted;c
 coordinatescanbesavedinStataorGnuPlot‐ASCIIformat.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.11???
18.6
DASPandjointdistributionfunctions
Themodulesjdistrubcanbeusedtodrawjointdistributionsurfaces.Thejointdistribution
function F ( x , y ) isdefinedas:
n
 w i I(x i  x)I(yi  y)
F̂(x, y)  i 1
n
 wi
i 1
Withthismodule:
 Thetwovariablesofinterest(dimensions)shouldbeselected;
 specificpopulationsubgroupscanbeselected;
 surfacesshowingthejointdistributionfunctionareplottedinteractivelywiththeGnuPlot
tool;
 coordinatescanbelisted;
 coordinatescanbesavedinStataorGnuPlot‐ASCIIformat.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.11
19 DASPandpro‐poorgrowth
19.1
DASPandpro‐poorindices
Themoduleipropoorestimatessimultaneouslythethreefollowingpro‐poorindices:
1. TheChenandRavallionpro‐poorindex(2003):
72
W ( z )  W2 ( z )
Index  1
F1( z )
where WD ( z ) istheWattsindexfordistribution D  1, 2 and F1( z ) istheheadcountfor
indexforthefirstdistribution,bothwithpovertylinesz.
2. TheKakwaniandPerniapro‐poorindex(2000):
Index 
P1( z, )  P2 ( z )
P1( z, )  P1( z( 1 / 2 ), )
3. TheKakwani,KhandkerandSonpro‐poorindex(2003):
Index _ 1  g





P1( z, )  P2 ( z )
P1( z, )  P1( z( 1 / 2 ), )
wheretheaveragegrowthis g( 2  1 ) / 1 andwhereasecondindexisgivenby:
Index _ 2  Index _ 1  g Onevariableofinterestshouldbeselectedforeachdistribution.
Conditionscanbespecifiedtofocusonspecificpopulationsubgroups.
Standarderrorsandconfidenceintervalswithaconfidencelevelof95%areprovided.Both
thetypeofconfidenceintervalsprovidedandthelevelofconfidenceusedcanbechanged.
Theresultsaredisplayedwith6decimals;thiscanbechanged.
Alevelfortheparameter  canbechosenforeachofthetwodistributions.
19.2
DASPandpro‐poorcurves
Pro‐poorcurvescanbedrawnusingeithertheprimalorthedualapproach.Theformerusesincome
levels.Thelatterisbasedonpercentiles.
19.2.1 Primalpro‐poorcurves
Thechangeinthedistributionfromstate1tostate2iss‐orderabsolutelypro‐poorwithstandard
cons if:
( z , s )   P2 ( z  cons,   s  1)  P1 ( z,   s  1)  <0  z  0,z +  Thechangeinthedistributionfromstate1tostate2iss‐orderrelativelypro‐poorif:



 ( z , s )  z  P2 ( z 2 ,   s  1)  P1  z ,   s  1  <0  z  0,z +  1


The module cpropoorp can be used to draw these primal pro‐poor curves and their associated
confidenceintervalbytakingintoaccountsamplingdesign.Themodulecan:
73
drawpro‐poorcurvesandtheirtwo‐sided,lower‐boundedorupper‐boundedconfidence
intervals;
 listorsavethecoordinatesofthedifferencesbetweenthecurvesaswellasthoseofthe
confidenceintervals;
 savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.

InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.13.
19.2.2 Dualpro‐poorcurves
Let:
Q( p) :quantileatpercentile p .
GL( p) :GeneralisedLorenzcurveatpercentile p .

:averagelivingstandards.
Thechangeinthedistributionfromstate1tostate2isfirst‐orderabsolutelypro‐poorwith
standardcons=0if:
( z , s )  Q2 ( p)  Q1 ( p)>0  p  0, p +  F ( z  )  orequivalentlyif:
( z, s) 
Q2 ( p)  Q1 ( p)
>0  p  0, p +  F ( z  )  Q1 ( p )
Thechangeinthedistributionfromstate1tostate2isfirst‐orderrelativelypro‐poorif:
( z, s) 
Q2 ( p) 2
- >0  p  0, p +  F ( z  )  Q1 ( p) 1
Thechangeinthedistributionfromstate1tostate2issecond‐orderabsolutelypro‐poorif:
( z , s )  GL2 ( p )  GL1 ( p )>0  p  0, p +  F ( z  )  orequivalentlyif:
( z, s) 
GL2 ( p )  GL1 ( p)
>0  p   0, p +  F ( z  )  GL1 ( p )
Thechangeinthedistributionfromstate1tostate2isfirst‐orderrelativelypro‐poorif:
74
( z, s) 
GL2 ( p ) 2
- >0  p   0, p +  F ( z  )  GL1 ( p ) 1
The module cpropoord can be used to draw these dual pro‐poor curves and their associated
confidenceintervalbytakingintoaccountsamplingdesign.Themodulecan:
 drawpro‐poorcurvesandtheirtwo‐sided,lower‐boundedorupper‐boundedconfidence
intervals;
 listorsavethecoordinatesofthedifferencesbetweenthecurvesaswellasthoseofthe
confidenceintervals;
 savethegraphsindifferentformats:
o *.gph:Stataformat;
o *.wmf:typicallyrecommendedtoinsertgraphsinWorddocuments;
o *.eps:typicallyrecommendedtoinsertgraphsinTex/Latexdocuments.
Manygraphicaloptionsareavailabletochangetheappearanceofthegraphs.
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.13
20 DASPandBenefitIncidenceAnalysis
20.1
Benefitincidenceanalysis
Themainobjectiveofbenefitincidenceistoanalysethedistributionofbenefitsfromtheuse
ofpublicservicesaccordingtothedistributionoflivingstandards.
Two main sources of information are used. The first informs on access of household
memberstopublicservices.Thisinformationcanbefoundinusualhouseholdsurveys.Thesecond
deals with the amount of total public expenditures on each public service. This information is
usuallyavailableatthenationallevelandsometimesinamoredisaggregatedformat,suchasatthe
regionallevel.Thebenefitincidenceapproachcombinestheuseofthesetwosourcesofinformation
toanalysethedistributionofpublicbenefitsanditsprogressivity.
Formally,let
bethesamplingweightofobservation i ;
wi bethelivingstandardofmembersbelongingtoobservation i (i.e.,percapitaincome);
yi s
bethenumberof“eligible”membersofobservationi,i.e.,membersthat“need”the
ei publicserviceprovidedbysectors.ThereareSsectors;
s
bethenumberofmembersofobservationi thateffectivelyusethepublicservice
fi providedbysectors;
bethesocio‐economicgroupofeligiblemembersofobservationi (typicallyclassified
gi byincomepercentiles);
75
beasubgroupindicatorforobservationi (e.g.,1foraruralresident,and2foranurban
resident).Eligiblememberscanthusbegroupedintopopulationexclusivesubgroups;
betotalpublicexpendituresonsector s inarea r .ThereareRareas(theareahere
referstothegeographicaldivisionwhichonecanhavereliableinformationontotal
publicexpendituresonthestudiedpublicservice);
ci E sr Es 
betotalpublicexpendituresonsector s  E s 

R

r 1

 Esr  .
Herearesomeofthestatisticsthatcanbecomputed.
1. Theshareofaginsector s isdefinedasfollows:
n
SH sg 
 w ifis I(i  g)
i 1
n

w i fis
i 1
G
Notethat:
 SHsg  1 .
g 1
2. Therateofparticipationofagroupginsector s isdefinedasfollows:
n
CR sg 
 w ifis I(i  g)
i 1
n

i 1
Thisratecannotexceed100%since f is
w i esi I(i  g)
 esi i .
3. Theunitcostofabenefitinsectorsforobservation j ,whichreferstothehousehold
membersthatliveinarea r :
UCsj

Esr
nr

j1
w jf js
where n r isthenumberofsampledhouseholdsinarear.
4. Thebenefitofobservation ifromtheuseofpublicsector s is:
Bsi  fis UCsi 5. Thebenefitofobservation i fromtheuseoftheSpublicsectorsis:
76
S
Bi   Bsi s 1
6. Theaveragebenefitatthelevelofthoseeligibletoaservicefromsectorsandforthose
observationsthatbelongtoagroup g ,isdefinedas:
n
ABEsg 
 w i Bsi I(i  g)
i 1
n

i 1
w i esi I(i  g)
7. Theaveragebenefitforthosethatusetheservice s andbelongtoagroup g isdefinedas:
n
s
ABFgs

 w i Bi I(i  g)
i 1
n
 w i fis I(i  g)
i 1
8. Theproportionofbenefitsfromtheservicefromsector s thataccruestoobservationsthat
belongtoagroup g isdefinedas:
PBsg 
where Bsg 
Bsg
Es
n
 w i Bsi I(i  g) .
i 1
These statistics can be restricted to specific socio‐demographic groups (e.g.,. rural/urban) by
replacing I(i  g) by I(i  c) .
.
Thebian.adomoduleallowsthecomputationofthesedifferentstatistics.
Somecharacteristicsofthemodule:
o Possibilityofselectingbetweenoneandsixsectors.
o Possibilityofusingfrequencydataapproachwheninformationabouttheleveloftotalpublic
expendituresisnotavailable.
o Generation of benefit variables by the type of public services (ex: primary, secondary and
tertiaryeducationlevels)andbysector.
o Generationofunitcostvariablesforeachsector.
o Possibilityofcomputingstatisticsaccordingtogroupsofobservations.
o Generationofstatisticsaccordingtosocial‐demographicgroups,suchasquartiles,quintiles
ordeciles.
77
Publicexpendituresonagivenserviceoftenvaryfromonegeographicaloradministrativeareato
another. When information about public expenditures is available at the level of areas, this
informationcanbeusedwiththebianmoduletoestimateunitcostmoreaccurately.
Example1
Observationi
1
2
3
4
5
HH EligibleHH
size members
7
4
5
6
4
3
2
5
3
2
Frequency
Areaindicator
2
2
3
2
1
1
1
1
2
2
Totallevel of
regionalpublic
expenditures
14000
14000
14000
12000
12000
Inthisexample,thefirstobservationcontainsinformationonhousehold1.
 Thishouseholdcontains7individuals;
 Threeindividualsinthishouseholdareeligibletothepublicservice;
 Only2amongthe3eligibleindividualsbenefitfromthepublicservice;
 This household lives in area 1. In this area, the government spends a total of 14000 to
providethepublicserviceforthe7usersofthisarea(2+2+3).
Theunitcostinarea1equals:14000/7=2000
Theunitcostinarea2equals:12000/3=4000
Bydefault,theareaindicatorissetto1forallhouseholds.Whenthisdefaultisused,thevariable
Regionalpublicexpenditures(thefifthcolumnthatappearsinthedialogbox)shouldbesettototal
public expenditures at the national level. This would occur when the information on public
expendituresisonlyavailableatthenationallevel.
Example2
Observationi HH
Eligible
Frequency
Areaindicator
Regionalpublic
size members
expenditures
1
7
3
2
1
28000
2
4
2
2
1
28000
3
5
5
3
1
28000
4
6
3
2
1
28000
5
4
2
1
1
28000
Theunitcostbenefit(atthenationallevel)equals:28000/10=2800
InterestedusersareencouragedtoconsidertheexercisesthatappearinSection23.14
78
21 Disaggregatinggroupeddata
TheungroupDASPmodulegeneratesdisaggregateddatafromaggregatedistributiveinformation.
Aggregate information is obtained from cumulative income shares (or Lorenz curve ordinates) at
somepercentiles.Forinstance:
Percentile(p)
0.10
0.30
0.50
0.60
0.90
1.00
Lorenzvalues:L(p)
0.02
0.10
0.13
0.30
0.70
1.00
Theusermustspecifythetotalnumberofobservationstobegenerated.Theusercanalsoindicate
the number of observations to be generated specifically at the top and/or at the bottom of the
distribution,inwhichcasetheproportion(in%)ofthepopulationfoundatthetoporatthebottom
mustalsobespecified.
Remarks:
 If only the total number of observations is set, the generated data are self weighted (or
uniformlydistributedoverpercentiles).
 Ifanumberofobservationsissetforthebottomand/ortoptails,thegenerateddataarenot
selfweightedandaweightvariableisprovidedinadditiontothegeneratedincomevariable.
 Example:Assumethatthetotalnumberofobservationstobegeneratedissetto1900,
but that we would like the bottom 10% of the population to be represented by 1000
observations.Inthiscase,weightswillequal1/1000forthebottom1000observations
and1/100fortheremainingobservations(thesumofweightsbeingnormalizedtoone).
 Thegeneratedincomevectortakesthenameof_yandthevectorweight,_w.
 The number of observations to be generated does not have to equal the number of
observations of the sample that was originally used to generate the aggregated data. The
ungroup module cannot in itself serve to estimate the sampling errors that would have
occurred had the original sample data been used to estimate poverty and/or inequality
estimates.
 Theusercanselectanysamplesizethatexceeds(number_of_classes+1),butitmaybemore
appropriateforstatisticalbias‐reductionpurposestoselectrelativelylargesizes.
STAGEIGeneratinganinitialdistributionofincomesandpercentiles
S.1.1:Generatingavectorofpercentiles
Starting from information on the importance of bottom and top groups and on the number of
observationstobegenerated,wefirstgenerateavectorofpercentiles.
79
Examples:
Notations:
NOBS:numberoftotalobservations
F:vectorofpercentiles
B_NOBS:numberofobservationsforthebottomgroup
T_NOBS:numberofobservationsforthetopgroup.
 ForNOBS=1000spreadequallyacrossallpercentiles,F=0.001,0.002...0.999,1.Toavoid
the value F=1 for the last generated observation, we can simply replace F by F‐
(0.5/NOBS).
 For NOBS=2800, B_NOBS=1000 and T_NOBS=1000, with the bottom and top groups
beingthefirstandlastdeciles:
a. F=0.0001,0.0002,...,0.0999,0.1000in0001/1000
b. F=0.1010,0.1020,…,0.8990,0.9000in1001/1800
c. F=0.9001,0.9002,...,0.9999,1.0000in1801/2800
AdjustmentscanalsobemadetoavoidthecaseofF(1)=1.
Theweightvectorcaneasilybegenerated.
S.1.2:Generatinganinitialdistributionofincomes
Theusermustindicatetheformofdistributionofthedisaggregateddata.
‐Normalandlognormaldistributions:
Assumethat x followsalognormaldistributionwithmean  andvariance  2 .TheLorenzcurveis
definedasfollows:
 Ln( x)  (    2 ) 
 Ln( x )   
L( p )   
 and p   







Weassumethat   1 andweestimatethevarianceusingtheproceduresuggestedbyShorrrocks
andWan(2008):avalueforthestandarddeviationoflogincomes,σ,isobtainedbyaveragingthe
m  1 estimatesof  k   1  pk    1  L( pk )  k  1, , m  1 where m isthenumberofclassesandΦisthestandardnormaldistributionfunction(Aitchisonand
Brown1957;KolenikovandShorrocks2005,Appendix).
‐GeneralizedQuadraticLorenzCurve:
Itisassumedthat:
L(1  L)  a( p 2  L)  bL( p  1)  c( p  L) Wecanregress L (1  L ) on ( p  L) , L( p  1) and ( p  L ) withoutanintercept,droppingthelast
observationsincethechosenfunctionalformforcesthecurvetogothrough(1,1).
2
2
2
b  2mp  n   mp  np  e 
Wehave Q ( p )   
2
4
0.5
80
e
 a  b  c 1
m 
n

b 2  4a 2be  4c
‐BetaLorenzCurve:
Itisassumedthat:
log  p  L   log( )   log( p )   log(1  p ) Afterestimatingtheparameters,wecangeneratequantilesasfollows
 
 
Q  p     p  1  p   


p
1
p




SeealsoDatt(1998).
‐TheSingh‐Maddaladistribution
ThedistributionfunctionproposedbySinghandMaddala(1976)takesthefollowingform:
q


1
F ( x)  1  
a 
1  ( x / b) 
where a  0, b  0, q  1/ a are parameters to be estimated. The income ( x ) is assumed to be
equaltoorgreaterthanzero.Thedensityfunctionisdefinedasfollows:

f ( x )   aq / b  1   x / b 
Quantilesaredefinedasfollows:

Q ( p )  b 1  p 

a  ( q 1)
1/ q
 x / b 

1
1/ a
a 1
WefollowJenkins(2008)’sapproachfortheestimationofparameters.Forthis,wemaximizethe
likelihood function, which is simply the product of density functions evaluated at the average
incomeofeachclass:
http://stata‐press.com/journals/stbcontents/stb48.pdf
STAGEIIAdjustingtheinitialdistributiontomatchtheaggregateddata(optional).
ThisstageadjuststheinitialvectorofincomesusingtheShorrocksandWan(2008)procedure.This
procedureproceedswithtwosuccessiveadjustments:
 Adjustment1:Correctingtheinitialincomevectortoensurethateachincomegrouphasits
originalmeanincome.
 Adjustment2:Smoothingtheinter–classdistributions.
The generated sample is saved automatically in a new Stata data file (called by default
ungroup_data.dta;namesanddirectoriescanbechanged).TheusercanalsoplottheLorenzcurves
oftheaggregated(whenweassumethateachindividualhastheaverageincomeofhisgroup)and
generateddata.
Dialogboxoftheungroupmodule
81
Figure 16: ungroup dialog box
IllustrationwithBurkinaFasohouseholdsurveydata
In this example, we use disaggregated data to generate aggregated information. Then, we
compare the density curve of the true data with those of the data generated through
disaggregationofthepreviouslyaggregateddata.
genfw=size*weight
Aggregatedinformation:
geny=exppc/r(mean)
clorenzy,hs(size)lres(1)
pL(p)
.1.0233349
.2.0576717
.3.0991386
.4.1480407
.5.2051758
.6.2729623
.7.3565971
.8.4657389
.9.6213571
11.00000
Density functions
(without adjustment)
(with adjustment)
0
0
.5
.5
1
1
1.5
1.5
Density functions
0
2
4
Normalised per capita expenditures
True distribition
Uniform
Generalized Quadratic LC
6
0
2
4
Normalised per capita expenditures
True distribition
Uniform
Generalized Quadratic LC
Log Normal
Beta LC
SINGH & MADALLA
82
Log Normal
Beta LC
SINGH & MADALLA
6
22 Appendices
22.1
AppendixA:illustrativehouseholdsurveys
22.1.1 The1994BurkinaFasosurveyofhouseholdexpenditures(bkf94I.dta)
Thisisanationallyrepresentativesurvey,withsampleselectionusingtwo‐stagestratifiedrandom
sampling.Sevenstratawereformed.Fiveofthesestratawereruralandtwowereurban.Primary
samplingunitsweresampledfromalistdrawnfromthe1985census.Thelastsamplingunitswere
households.
Listofvariables
strata
Stratuminwhichahouseholdlives
psu
Primarysamplingunit
weight
Samplingweight
size
Householdsize
exp
Totalhouseholdexpenditures
expeq
Totalhouseholdexpendituresperadultequivalent
expcp
Totalhouseholdexpenditurespercapita
gse
Socio‐economicgroupofthehouseholdhead
1wage‐earner(publicsector)
2wage‐earner(privatesector)
3Artisanortrader
4Othertypeofearner
5Cropfarmer
6Subsistencefarmer
7Inactive
sex
Sexofhouseholdhead
1Male
2Female
zone
Residentialarea
1Rural
2Urban
83
22.1.2 The1998BurkinaFasosurveyofhouseholdexpenditures(bkf98I.dta)
Thissurveyissimilartothe1994one,althoughtenstratawereusedinsteadofsevenfor1994.To
express 1998 data in 1994 prices, two alternative procedures have been used. First, 1998
expendituredataweremultipliedbytheratioofthe1994officialpovertylinetothe1998official
poverty line: z_1994/z_1998. Second, 1998 expenditure data were multiplied by the ratio of the
1994consumerpriceindextothe1998consumerpriceindex:ipc_1994/ipc_1998.
Listofnewvariables
expcpz Totalhouseholdexpenditurespercapitadeflatedby(z_1994/z_1998)
Totalexpenditurespercapitadeflatedby(ipc_1994/ipc_1998)
expcpi
22.1.3
CanadianSurveyofConsumerFinance(asubsampleof1000
observations–can6.dta)
Listofvariables
X
Yearlygrossincomeperadultequivalent.
T
Incometaxesperadultequivalent.
B1
Transfer1peradultequivalent.
B2
Transfer2peradultequivalent.
B3
Transfer3peradultequivalent.
B
SumoftransfersB1,B2andB3
N
Yearlynetincomeperadultequivalent(X minusT plusB)
22.1.4 PeruLSMSsurvey1994(Asampleof3623householdobservations‐
PEREDE94I.dta)
Listofvariables
exppc
Totalexpenditures,percapita(constantJune1994solesperyear).
weight
Samplingweight
84
size
npubprim
npubsec
npubuniv
Householdsize
Numberofhouseholdmembersinpublicprimaryschool
Numberofhouseholdmembersinpublicsecondaryschool
Numberofhouseholdmembersinpublicpost‐secondaryschool
22.1.5 PeruLSMSsurvey1994(Asampleof3623householdobservations–
PERU_A_I.dta)
Listofvariables
hhid
HouseholdId.
exppc
Totalexpenditures,percapita(constantJune1994solesperyear).
size
Householdsize
literate
Numberofliteratehouseholdmembers
pliterate
literate/size
22.1.6 The1995ColombiaDHSsurvey(columbiaI.dta)
ThissampleisapartoftheDatafromtheDemographicandHealthSurveys(Colombia_1995)witch
containsthefollowinginformationforchildrenaged0‐59months
Listofvariables
hid Householdid
haz height‐for‐age
waz weight‐for‐age
whz weight‐for‐height
sprob survivalprobability
wght samplingweight
Asset
assetindex
22.1.7 The1996DominicanRepublicDHSsurvey
(Dominican_republic1996I.dta)
ThissampleisapartoftheDatafromtheDemographicandHealthSurveys(Republic
Dominican_1996)witchcontainsthefollowinginformationforchildrenaged0‐59months
85
Listofvariables
hid Householdid
haz height‐for‐age
waz weight‐for‐age
whz weight‐for‐height
sprob survivalprobability
wght samplingweight
Asset
assetindex
22.2


AppendixB:labellingvariablesandvalues
Thefollowing.dofilecanbeusedtosetlabelsforthevariablesinbkf94.dta.
Formoredetailsontheuseoflabelcommand,typehelplabelinthecommandwindow.
=================================lab_bkf94.do==================================
#delim;
/*Todropalllabelvalues*/
labeldrop_all;
/*Toassignlabels*/
labelvarstrata"Stratuminwhichahouseholdlives";
labelvarpsu"Primarysamplingunit";
labelvarweight"Samplingweight";
labelvarsize"Householdsize";
labelvartotexp"Totalhouseholdexpenditures";
labelvarexppc"Totalhouseholdexpenditurespercapita";
labelvarexpeq"Totalhouseholdexpendituresperadultequivalent";
labelvargse"Socio‐economicgroupofthehouseholdhead";
/*Todefinethelabelvaluesthatwillbeassignedtothecategoricalvariablegse*/
labeldefinelvgse
1"wage‐earner(publicsector)"
2"wage‐earner(privatesector)"
3"Artisanortrader"
4"Othertypeofearner"
5"Cropfarmer"
6"Subsistencefarmer"
7"Inactive"
;
/*Toassignthelabelvalues"lvgse"tothevariablegse*/
labelvalgselvgse;
labelvarsex"Sexofhouseholdhead";
86
labeldeflvsex
1Male
2Female
;
labelvalsexlvsex;
labelvarzone"Residentialarea";
labeldeflvzone
1Rural
2Urban
;
labelvalzonelvzone;
====================================End======================================
22.3
AppendixC:settingthesamplingdesign
Tosetthesamplingdesignforthedatafilebkf94.dta,openthedialogboxforthecommandsvyset
bytypingthesyntaxdbsvysetinthecommandwindow.IntheMainpanel,setSTRATAandSAMPLING
UNITSasfollows:
Figure17:Surveydatasettings
IntheWeightspanel,setSAMPLINGWEIGHTVARIABLEasfollows:
87
Figure18:Settingsamplingweights
ClickonOKandsavethedatafile.
Tocheckifthesamplingdesignhasbeenwellset,typethecommandsvydes.Thefollowingwillbe
displayed:
88
23 Examplesandexercises
23.1
EstimationofFGTpovertyindices
“HowpoorwasBurkinaFasoin1994?”
1. Open the bkf94.dta file and label variables and values using the information of Section
22.1.1.Typethedescribecommandandthenlabellisttolistlabels.
2. UsetheinformationofSection22.1.1.tosetthesamplingdesignandthensavethefile.
3. Estimatetheheadcountindexusingvariablesofinterestexpccandexpeq.
a. You should set SIZE to household size in order to estimate poverty over the
populationofindividuals.
b. Usetheso‐called1994officialpovertylineof41099FrancsCFAperyear.
4. Estimate the headcount index using the same procedure as above except that the poverty
lineisnowsetto60%ofthemedian.
5. Usingtheofficialpovertyline,howdoestheheadcountindexformale‐andfemale‐headed
householdscompare?
6. Can you draw a 99% confidence interval around the previous comparison? Also, set the
numberofdecimalsto4.
Answer
Q.1
Ifbkf94.dtaissavedinthedirectoryc:/data,typethefollowingcommandtoopenit:
use"C:\data\bkf94.dta",clear
Iflab_bkf94.doissavedinthedirectoryc:/do_files,typethefollowingcommandtolabelvariables
andlabels:
do"C:\do_files\lab_bkf94.do"
Typingthecommanddescribe,weobtain:
obs:
8,625 vars:
9
31Oct200613:48
size:
285,087(99.6%of
memoryfree)
storagedisplay value
variable name type format label
weight float %9.0g size
byte %8.0g strata byte %8.0g psu
byte %8.0g gse
byte %29.0g gse
sex
byte %8.0g sex
zone
byte %8.0g
zone
exp
double %10.0g expeq double %10.0g exppc float %9.0g Typinglabellist,wefind:
zone:
1
2
variablelabel
Samplingweight
Householdsize
Stratuminwhichahouseholdlives
Primarysamplingunit
Socio‐economicgroupofthehouseholdhead
Sexofhouseholdhead
Residentialarea
Totalhouseholdexpenditures
Totalhouseholdexpendituresperadultequivalent
Totalhouseholdexpenditurespercapita
Rural
Urban
89
sex:
gse:
1
2
Male
Female
1
2
3
4
5
6
7
wage‐earner(publicsector)
wage‐earner(privatesector)
Artisanortrader
Othertypeofearner
Cropfarmer
Foodfarmer
Inactive
Q.2
Youcansetthesamplingdesignwithadialogbox,asindicatedinSection22.3,orsimplybytyping
svysetpsu[pweight=weight],strata(strata)vce(linearized)
Typingsvydes,weobtain
Q.3
TypebdifgttoopenthedialogboxfortheFGTpovertyindexandchoosevariablesandparameters
asindicatedinthefollowingwindow.ClickonSUBMIT.
90
Figure19:EstimatingFGTindices
Thefollowingresultsshouldthenbedisplayed:
Q.4
SelectRELATIVEforthepovertylineandsettheotherparametersasabove.
91
Figure20:EstimatingFGTindiceswithrelativepovertylines
AfterclickingonSUBMIT,thefollowingresultsshouldbedisplayed:
Q.5
Setthegroupvariabletosex.
92
Figure21:FGTindicesdifferentiatedbygender
ClickingonSUBMIT,thefollowingshouldappear:
Q.6
UsingthepanelCONFIDENCEINTERVAL,settheconfidencelevelto99%andsetthenumberof
decimalsto4intheRESULTSpanel.
93
94
23.2
EstimatingdifferencesbetweenFGTindices.
“HaspovertyBurkinaFasodecreasedbetween1994and1998?”
1. OpenthedialogboxforthedifferencebetweenFGTindices.
2. Estimatethedifferencebetweenheadcountindiceswhen
a. Distribution1isyear1998anddistribution2isyear1994;
b. Thevariableofinterestisexppcfor1994andexppczfor1998.
c. You should set size to household size in order to estimate poverty over the
populationofindividuals.
d. Use41099FrancsCFAperyearasthepovertylineforbothdistributions.
3. Estimatethedifferencebetweenheadcountindiceswhen
a. Distribution1isruralresidentsinyear1998anddistribution2isruralresidentsin
year1994;
b. Thevariableofinterestisexppcfor1994andexppczfor1998.
c. You should set size to household size in order to estimate poverty over the
populationofindividuals.
d. Use41099FrancsCFAperyearasthepovertylineforbothdistributions.
4. Redothelastexerciseforurbanresidents.
5. Redothelastexerciseonlyformembersofmale‐headedhouseholds.
6. Testiftheestimateddifferenceinthelastexerciseissignificantlydifferentfromzero.Thus,
test:
H 0 : P( z  41099,   0)  0 against H1 : P( z  41099,   0)  0 Set the significance level to 5% and assume that the test statistics follows a normal
distribution.
Answers
Q.1
Openthedialogboxbytyping
dbdifgt
Q.2
 Fordistribution1,choosetheoptionDATAINFILEinsteadofDATAINMEMORYandclickon
BROWSEtospecifythelocationofthefilebkf98I.dta.
 Followthesameprocedurefordistribution2tospecifythelocationofbkf94I.dta.
 Choosevariablesandparametersasfollows:
95
Figure22:EstimatingdifferencesbetweenFGTindices
AfterclickingonSUBMIT,thefollowingshouldbedisplayed:
96
Q.3

Restricttheestimationtoruralresidentsasfollows:
o SelecttheoptionCondition(s)
o WriteZONEinthefieldnexttoCONDITION(1)andtype1inthenextfield.
Figure23:EstimatingdifferencesinFGTindices
AfterclickingonSUBMIT,weshouldsee:
Q.4
97
Onecanseethatthechangeinpovertywassignificantonlyforurbanresidents.Q.5
Restricttheestimationtomale‐headedurbanresidentsasfollows:
o SetthenumberofCondition(s)to2;
o SetsexinthefieldnexttoCondition(2)andtype1inthenextfield.
Figure24:FGTdifferencesacrossyearsbygenderandzone
AfterclickingonSUBMIT,thefollowingshouldbedisplayed:
Q.6
98
Wehavethat:
LowerBound:=0.0222
UpperBound:=0.1105
Thenullhypothesisisrejectedsincethelowerboundofthe95%confidenceintervalisabovezero.
23.3
Estimatingmultidimensionalpovertyindices
“Howmuchisbi‐dimensionalpoverty(totalexpendituresandliteracy)inPeruin1994?”
Usingtheperu94I.dtafile,
1. EstimatetheChakravartyetal(1998)indexwithparameteralpha=1and
Pov.line
a_j
Var.ofinterest
Dimension1
exppc
400
1
Dimension2
pliterate
0.90
1
2. EstimatetheBourguignonandChakravarty(2003)indexwithparameters
alpha=beta=gamma=1and
Pov.line
Var.ofinterest
Dimension1
exppc
400
Dimension2
literate
0.90
Q.1
Steps:
 Type
use"C:\data\ peru94_A_I.dta",clear
 Toopentherelevantdialogbox,type
dbimdp_bci
 Choosevariablesandparametersasin
99
Figure25:Estimatingmultidimensionalpovertyindices(A)
AfterclickingSUBMIT,thefollowingresultsappear.
Q.2

Toopentherelevantdialogbox,type
dbimdp_cmr
Steps:
 Choosevariablesandparametersasin
100
Figure26:Estimatingmultidimensionalpovertyindices(B)
AfterclickingSUBMIT,thefollowingresultsappear.
101
23.4
EstimatingFGTcurves.
“Howsensitivetothechoiceofapovertylineistherural‐urbandifferenceinpoverty?”
1. Openbkf94I.dta
2. OpentheFGTcurvesdialogbox.
3. DrawFGTcurvesforvariablesofinterestexppcandexpeqwith
a. parameter   0 ;
b. povertylinebetween0and100,000FrancCFA;
c. sizevariablesettosize;
d. subtitleofthefiguresetto“Burkina1994”.
4. DrawFGTcurvesforurbanandruralresidentswith
a. variableofinterestsettoexpcap;
b. parameter   0 ;
c. povertylinebetween0and100,000FrancCFA;
d. sizevariablesettosize.
5. Drawthedifferencebetweenthesetwocurvesand
a. save the graph in *.gph format to be plotted in Stata and in *.wmf format to be
insertedinaWorddocument.
b. Listthecoordinatesofthegraph.
6. Redothelastgraphwith   1 .
Answers
Q.1
Openthefilewith
use"C:\data\bkf94I.dta",clear
Q.2
Openthedialogboxbytyping
dbdifgt
Q.3
Choosevariablesandparametersasfollows:
102
Figure27:DrawingFGTcurves
Tochangethesubtitle,selecttheTitlepanelandwritethesubtitle.
Figure28:EditingFGTcurves
AfterclickingSUBMIT,thefollowinggraphappears:
103
Figure29:GraphofFGTcurves
104
Q.4
Choosevariablesandparametersasinthefollowingwindow:
Figure30:FGTcurvesbyzone
AfterclickingSUBMIT,thefollowinggraphappears:
105
Figure31:GraphofFGTcurvesbyzone
106
Q.5




ChoosetheoptionDIFFERENCEandselect:WITHTHEFIRSTCURVE;
Indicatethatthegroupvariableiszone;
SelecttheResultspanelandchoosetheoptionLISTintheCOORDINATESquadrant.
IntheGRAPHquadrant,selectthedirectoryinwhichtosavethegraphingphformatandto
exportthegraphinwmfformat.
Figure32:DifferencesofFGTcurves
107
Figure33:Listingcoordinates
108
AfterclickingSUBMIT,thefollowingappears:
Figure34:DifferencesbetweenFGTcurves
Q.6
109
Figure35:DifferencesbetweenFGTcurves
23.5
EstimatingFGTcurvesanddifferencesbetweenFGTcurveswith
confidenceintervals
“Isthepovertyincreasebetween1994and1998inBurkinaFasostatisticallysignificant?”
1) Using the file bkf94I.dta, draw the FGT curve and its confidence interval for the variable of
interestexppcwith:
a) parameter   0 ;
b) povertylinebetween0and100,000FrancCFA;
c) sizevariablesettosize.
2) Using simultaneously the files bkf94I.dta and bkf98I.dta, draw the difference between FGT
curvesandassociatedconfidenceintervalswith:
a) Thevariableofinterestexppcfor1994andexppczfor1998.
b) parameter   0 ;
c) povertylinebetween0and100,000FrancCFA;
d) sizevariablesettosize.
3) Redo2)withparameter   1 .
Answers
Q.1
110
Steps:
 Type
use"C:\data\bkf94I.dta",clear
 Toopentherelevantdialogbox,type
dbcfgts
 Choosevariablesandparametersasin
Figure36:DrawingFGTcurveswithconfidenceinterval
AfterclickingSUBMIT,thefollowingappears:
111
Figure37:FGTcurveswithconfidenceinterval
FGT curve (alpha = 0)
0
.2
.4
.6
.8
Burkina Faso
0
20000
40000
60000
80000
100000
Poverty line (z)
Confidence interval (95 %)
Estimate
Q.2
Steps:
 Toopentherelevantdialogbox,type
dbcfgtsd2
 Choosevariablesandparametersasin
112
Figure38:DrawingthedifferencebetweenFGTcurveswithconfidenceinterval
Figure39:DifferencebetweenFGTcurveswithconfidenceinterval (  0) Difference between FGT curves
-.1
-.05
0
.05
(alpha = 0)
0
20000
40000
60000
80000
100000
Poverty line (z)
Confidence interval (95 %)
Estimated difference
113
Figure40:DifferencebetweenFGTcurveswithconfidenceinterval (  1) Difference between FGT curves
-.04
-.02
0
.02
(alpha = 1)
0
20000
40000
60000
80000
100000
Poverty line (z)
Confidence interval (95 %)
Estimated difference
23.6
Testingpovertydominanceandestimatingcriticalvalues.
“HasthepovertyincreaseinBurkinaFasobetween1994and1998beenstatisticallysignificant?”
1) Usingsimultaneouslyfilesbkf94I.dtaandbkf98I.dta,checkforsecond‐orderpovertydominance
andestimatethevaluesofthepovertylineatwhichthetwoFGTcurvescross.
a) Thevariableofinterestisexppcfor1994andexppczfor1998;
b) Thepovertylineshouldvarybetween0and100,000FrancCFA;
c) Thesizevariableshouldbesettosize.
Answers
Q.1
Steps:
 Toopentherelevantdialogbox,type
dbdompov
 Choosevariablesandparametersasin
114
Figure41:Testingforpovertydominance
AfterclickingSUBMIT,thefollowingresultsappear:
23.7
DecomposingFGTindices.
“WhatisthecontributionofdifferenttypesofearnerstototalpovertyinBurkinaFaso?” 1. Openbkf94I.dtaanddecomposetheaveragepovertygap
a. withvariableofinterestexppc;
b. withsizevariablesettosize;
c. attheofficialpovertylineof41099FrancsCFA;
d. andusingthegroupvariablegse(Socio‐economicgroups).
2. Dotheaboveexercisewithoutstandarderrorsandwiththenumberofdecimalssetto4.
115
Answers
Q.1
Steps:
 Type
use"C:\data\bkf94I.dta",clear
 Toopentherelevantdialogbox,type
dbdfgtg
 Choosevariablesandparametersasin
Figure42:DecomposingFGTindicesbygroups
AfterclickingSUBMIT,thefollowinginformationisprovided:
116
Q.2
UsingtheRESULTSpanel,changethenumberofdecimalsandunselecttheoptionDISPLAY STANDARD
ERRORS.
AfterclickingSUBMIT,thefollowinginformationisobtained:
117
23.8
EstimatingLorenzandconcentrationcurves.
“HowmuchdotaxesandtransfersaffectinequalityinCanada?”
Byusingthecan6.dtafile,
1. Draw the Lorenz curves for gross income X and net income N. How can you see the
redistributionofincome?
2. Draw Lorenz curves for gross income X and concentration curves for each of the three
transfers B1, B2 and B3 and the tax T. What can you say about the progressivity of these
elementsofthetaxandtransfersystem?
“WhatistheextentofinequalityamongBurkinaFasoruralandurbanhouseholdsin1994?”
Byusingthebkf94I.dtafile,
3. DrawLorenzcurvesforruralandurbanhouseholds
a. withvariableofinterestexppc;
b. withsizevariablesettosize;
c. andusingthegroupvariablezone(asresidentialarea).
Q.1
Steps:
 Type
use"C:\data\can6.dta",clear
 Toopentherelevantdialogbox,type
dbclorenz
 Choosevariablesandparametersasin
118
Figure43:Lorenzandconcentrationcurves
AfterclickingSUBMIT,thefollowingappears:
119
Figure44:Lorenzcurves
Q.2
Steps:

Choosevariablesandparametersasin
120
Figure45:Drawingconcentrationcurves
AfterclickingonSUBMIT,thefollowingappears:
121
Figure46:Lorenzandconcentrationcurves
Q.3
Steps:
 Type
use"C:\data\bkf94I.dta",clear
 Choosevariablesandparametersasin
122
Figure47:DrawingLorenzcurves
Figure48:Lorenzcurves
123
23.9
EstimatingGiniandconcentrationcurves
“ByhowmuchdotaxesandtransfersaffectinequalityinCanada?”
Usingthecan6.dtafile,
1. EstimatetheGiniindicesforgrossincomeXandnetincomeN.
2. Estimate the concentration indices for variables T and N when the ranking variable is
grossincomeX.
“ByhowmuchhasinequalitychangedinBurkinaFasobetween1994and1998?”
Usingthebkf94I.dtafile,
3. EstimatethedifferenceinBurkinaFaso’sGiniindexbetween1998and1994
a. withvariableofinterestexpeqzfor1998andexpeqfor1994;
b. withsizevariablesettosize.
Q.1
Steps:
 Type
use"C:\data\can6.dta",clear
 Toopentherelevantdialogbox,type
dbigini
 Choosevariablesandparametersasin
124
Figure49:EstimatingGiniandconcentrationindices
AfterclickingSUBMIT,thefollowingresultsareobtained:
Q.2
Steps:

Choosevariablesandparametersasin
125
Figure50:Estimatingconcentrationindices
AfterclickingSUBMIT,thefollowingresultsareobtained:
Q.3
Steps:
 Toopentherelevantdialogbox,type
dbdigini
 Choosevariablesandparametersasin
126
Figure51:EstimatingdifferencesinGiniandconcentrationindices
AfterclickingSUBMIT,thefollowinginformationisobtained:
127
23.10 Usingbasicdistributivetools
“WhatdoesthedistributionofgrossandnetincomeslooklikeinCanada?”
Usingthecan6.dtafile,
1. DrawthedensityforgrossincomeXandnetincomeN.
‐ Therangeforthexaxisshouldbe[0,60000].
2. DrawthequantilecurvesforgrossincomeXandnetincomeN.
‐ Therangeofpercentilesshouldbe[0,0.8]
3. Drawtheexpectedtax/benefitaccordingtogrossincomeX.
‐ Therangeforthexaxisshouldbe[0,60000]
‐ Usealocallinearestimationapproach.
4. EstimatemarginalratesfortaxesandbenefitsaccordingtogrossincomeX.
‐ Therangeforthexaxisshouldbe[0,60000]
‐ Usealocallinearestimationapproach.
Q.1
Steps:
 Type
use"C:\data\can6.dta",clear
 Toopentherelevantdialogbox,type
dbcdensity
 Choosevariablesandparametersasin
Figure52:Drawingdensities
128
AfterclickingSUBMIT,thefollowingappears:
Figure53:Densitycurves
.00003
0
.00001
.00002
f(y)
.00004
.00005
Density Curves
0
12000
24000
36000
48000
60000
y
X
Q.2
Steps:
 Toopentherelevantdialogbox,type
dbc_quantile
 Choosevariablesandparametersasin
129
N
Figure54:Drawingquantilecurves
AfterclickingSUBMIT,thefollowingappears:
Figure55:Quantilecurves
0
10000
Q(p)
20000
30000
Quantile Curves
0
.2
.4
Percentiles (p)
X
130
.6
.8
N
Q.3
Steps:
 Toopentherelevantdialogbox,type
dbcnpe
 Choosevariablesandparametersasin
Figure56:Drawingnon‐parametricregressioncurves
AfterclickingSUBMIT,thefollowingappears:
131
Figure57:Non‐parametricregressioncurves
20000
Non parametric regression
10000
0
5000
E(Y|X)
15000
(Linear Locally Estimation Approach | Bandwidth = 3699.26 )
0
12000
24000
36000
48000
60000
X values
t
b
Q.4
Steps:
 Choosevariablesandparametersasin
132
Figure58:Drawingderivativesofnon‐parametricregressioncurves
AfterclickingSUBMIT,thefollowingappears:
Figure59:Derivativesofnon‐parametricregressioncurves
Non parametric derivative regression
0
-.5
-1
dE[Y|X]/dX
.5
1
(Linear Locally Estimation Approach | Bandwidth = 3699.26 )
0
12000
24000
36000
48000
60000
X values
t
133
b
23.11 Plottingthejointdensityandjointdistributionfunction
“WhatdoesthejointdistributionofgrossandnetincomeslooklikeinCanada?”
Usingthecan6.dtafile,
4. EstimatethejointdensityfunctionforgrossincomeXandnetincomeN.
o Xrange:[0,60000]
o Nrange:[0,60000]
5. EstimatethejointdistributionfunctionforgrossincomeXandnetincomeN.
o Xrange:[0,60000]
o Nrange:[0,60000]
Q.1
Steps:
 Type
use"C:\data\can6.dta",clear
 Toopentherelevantdialogbox,type
dbsjdensity
 Choosevariablesandparametersasin
Figure60:Plottingjointdensityfunction
AfterclickingSUBMIT,thefollowinggraphisplottedinteractivelywithGnuPlot4.2:
134
Joint Density Function
f(x,y)
3e-009
2.5e-009
2e-009
1.5e-009
1e-009
5e-010
0
0
10000
20000
0
10000
30000
Dimension 1
40000
20000
30000
Dimension 2
40000
50000
50000
6000060000
Q.2
Steps:
 Toopentherelevantdialogbox,type
dbsjdistrub
 Choosevariablesandparametersasin
135
Figure61:Plottingjointdistributionfunction
AfterclickingSUBMIT,thefollowinggraphisplottedinteractivelywithGnuPlot4.2:
Joint Distribution Function
F(x,y)
1
0.9
0.8
0.7
0.6
0.5
0.4
0.3
0.2
0.1
0
60000
50000
40000
30000
20000
Dimension 2
10000
0 0
10000
40000
30000
20000 Dimension 1
50000
60000
136
23.12 Testingthebi‐dimensionalpovertydominance
Using the columbia95I.dta (distribution_1) and the dominican_republic95I.dta (distribution_2)
files,
1.
Draw the difference between the bi‐dimensional multiplicative FGT surfaces and the
confidenceintervalofthatdifferencewhen
Range
alpha_j
Var.ofinterest
Dimension1
haz:height‐for‐age
‐3.0/6.0
0
Dimension2
sprob:survival
0.7/1.0
0
probability
2.
Testforbi‐dimensionalpovertyusingtheinformationabove.
Answer:
Q.1
Steps:
 Toopentherelevantdialogbox,type
dbdombdpov
 Choosevariablesandparametersasin
137
Figure62:Testingforbi‐dimensionalpovertydominance
AfterclickingSUBMIT,thefollowinggraphisplottedinteractivelywithGnuPlot4.2:
Bi-dimensional poverty dominance
0.5
0.4
0.3
0.2
0.1
0
-0.1
-0.2
-0.3
-0.4
6
Difference
Lower-bounded
Upper-bounded
5
4
3
2
1
Dimension 1
0
-1
-2
-3 1
0.8
0.840.82
0.880.86
0.9
0.940.92
Dimension 2
0.980.96
0.78
Q.2
138
To make a simple test of multidimensional dominance, one should check if the lower‐bounded
confidenceintervalsurfaceisalwaysabovezeroforallcombinationsofrelevantpovertylines–or
conversely.
o Forthis,clickonthepanel“Confidenceinterval”andselecttheoptionlower‐bounded.
o ClickagainonthebuttonSubmit.
AfterclickingSUBMIT,thefollowinggraphisplottedinteractivelywithGnuPlot4.2:
Bi-dimensional poverty dominance
Lower-bounded
0.05
0
-0.05
-0.1
-0.15
-0.2
-0.25
-0.3
-0.35
-3
-2
-1
0
Dimension 1
1
2
3
4
0.96
0.9 0.92 0.94
0.88
5
0.86
0.84
6 0.78 0.8 0.82
Dimension 2
0.98 1
139
23.13 Testingforpro‐poornessofgrowthinMexico
The three sub‐samples used in these exercises are sub‐samples of 2000 observations drawn
randomlyfromthethreeENIGHMexicanhouseholdsurveysfor1992,1998and2004.Eachofthese
threesub‐samplescontainsthefollowingvariables:
strata Thestratum
psu
Theprimarysamplingunit
weight Samplingweight
inc
Income
hhsz
Householdsize
1. Usingthefilesmex_92_2mI.dtaandmex_98_2mI.dta,testforfirst‐orderrelativepro‐
poornessofgrowthwhen:
 Theprimalapproachisused.
 Therangeofpovertylinesis[0,3000].
2. Repeatwiththedualapproach.
3. Byusingthefilesmex_98_2mI.dtaandmex_04_2mI.dta,testforabsolutesecond‐orderpro‐
poornesswiththedualapproach.
4. Usingmex_98_2mI.dtaandmex_04_2mI.dta,estimatethepro‐poorindicesofmodule
ipropoor.
 Parameteralphasetto1.
 Povertylineequalto600.
Answer:
Q.1
Steps:
 Toopentherelevantdialogbox,type
dbcpropoorp
140
Choosevariablesandparametersasin(selecttheupper‐boundedoptionfortheconfidence
interval):
Figure63:Testingthepro‐poorgrowth(primalapproach)

AfterclickingSUBMIT,thefollowinggraphappears
141
Relative propoor curve
-.15
-.1
-.05
0
.05
(Order : s=1 | Dif. = P_2( (m2/m1)z, a=s-1) - P_1(z,a=s-1))
0
600
Difference
Null horizontal line
1200
1800
Poverty line (z)
2400
3000
Upper bound of 95% confidence interval
Q.2
Steps:
 Toopentherelevantdialogbox,type
dbcpropoord
 Choose variables and parameters as in (with the lower‐bounded option for the confidence
interval):
Figure64:Testingthepro‐poorgrowth(dualapproach)‐A
142
AfterclickingSUBMIT,thefollowinggraphappears
Absolute propoor curves
-.4
-.2
0
.2
.4
(Order : s=1 | Dif. = Q_2(p) /Q_1(p) - mu_2/mu_1 )
0
.184
.368
.552
Percentiles (p)
Difference
Null horizontal line
.736
.92
Lower bound of 95% confidence interval
Q.2
Steps:
143
 Toopentherelevantdialogbox,type
dbcpropoord
 Choose variables and parameters as in (with the lower‐bounded option for the confidence
interval):
Figure65:Testingthepro‐poorgrowth(dualapproach)–B
AfterclickingSUBMIT,thefollowinggraphappears
144
Absolute propoor curves
0
2
4
6
(Order : s=2 | Dif. = (GL_2(p) - GL_1(p) ) / GL_2(p) )
0
.184
.368
.552
Percentiles (p)
Difference
Null horizontal line
Q.4
Steps:
 Toopentherelevantdialogbox,type
dbipropoor
 Choosevariablesandparametersas.
.736
.92
Lower bound of 95% confidence interval
145
AfterclickingSUBMIT,thefollowingresultsappear:
23.14 BenefitincidenceanalysisofpublicspendingoneducationinPeru
(1994).
1. Usingtheperedu94I.dtafile,estimateparticipationandcoverageratesoftwotypesofpublic
spendingoneducationwhen:
‐ Thestandardoflivingisexppc
‐ The number of household members that benefit from education is fr_prim for the
primarysectorandfr_secforthesecondaryone.
‐ The number of eligible household members is el_prim for the primary sector and
el_secforthesecondaryone.
‐ Socialgroupsarequintiles.
146
Answer:
Typedbbianinthewindowscommandandsetvariablesandoptionsasfollows:
Figure66:Benefitincidenceanalysis
AfterclickingonSubmit,thefollowingappears:
147
To estimate total public expenditures on education by sector at the national level, the
followingmacroinformationwasused:
‐ Pre‐primary and primary public education expenditure (as % of all levels), 1995:
35.2%
‐ Secondarypubliceducationexpenditure(as%ofalllevels),1995:21.2%
‐ Tertiarypubliceducationexpenditure(as%ofalllevels),1995:16%
‐ Publiceducationexpenditure(as%ofGNP),1995=3%
‐ GDPpercapita:about3800.
Usingthisinformation,thefollowingvariablesaregenerated
capdrop_var1;
gen_var1=size*weight*3800;
quisum_var1;
quigenpri_pub_exp=0.03*0.352*`r(sum)';
quigensec_pub_exp=0.03*0.212*`r(sum)';
quigenuni_pub_exp=0.03*0.160*`r(sum)';
capdrop_var1;
‐ Totalpublicexpendituresonprimarysector:pri_pub_exp
‐ Totalpublicexpendituresonsecondarysector:sec_sec_exp
‐ Totalpublicexpendituresonuniversitysector:uni_pub_exp
Estimatetheaveragebenefitsperquintileandgeneratethebenefitvariables.
Answer:
Setvariablesandoptionsasfollows:
2.
148
Figure67:BenefitIncidenceAnalysis(unitcostapproach)
AfterclickingonSubmit,thefollowingappears:
149
150