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ONEXP1.2 U SER M ANUAL TheofficialhomepageofOnExpis:http://onexp.textstrukturen.uni‐goettingen.de Onexpisanexperimentalsoftwarethatgivesyouthepowerandflexibilitytocreateweb‐based experimentsinamatterofminutes.Butfirst,youneedtounderstand,howonexpworks.Iwill giveyouasimpleexampletostartwith. 1.GETTINGTHEIDEA! 1.1.WHATYOUNEEDFORANEXPERIMENT Youwantanicelittleexperimentinwhichyouhavetenquestionsandforeachofthem,you wanttogivethreeansweroptions,withtextsthatdifferfromquestiontoquestion,likethis.So youwantparticipantstoseesomethinglikethis: Dearparticipant–pleaseanswerthefollowingquestion: Question1 Chooseoneoftheseanswers Answer1specifictoquestion1 Answer2specifictoquestion1 Answer3specifictoquestion1 submit submit AndthenyouwanttoshowQuestion2,whitthespecificanswers: Dearparticipant–pleaseanswerthefollowingquestion: Question2 Chooseoneoftheseanswers Answer1specifictoquestion2 Answer2specifictoquestion2 Answer3specifictoquestion2 Firstthingyouneed,isthelistofstimuli.Letuscreateatextfilecalledinput1.txtinwhichyou justwriteupyourquestionsandalltheanswers.Ofcourseyoudon’twrite“question1”inyour file,butinsteadyourquestion1e.g.WhatdoyouthinkaboutOnExp?. input1.txt Question1 answer1q1 answer2q1 answer3q1 Question2 answer1q2 answer2q2 answer3q2 … Now,OnExpwillwanttoknowhowyourpageshouldlooklike.Thereisnoway,OnExpcan guessthatyouwantyouranswersonebelowtheother,howmanyofthelinesintheinput1.txt shouldappearatonceetc.Whileotherprogramswillgiveyoueitherawhatyouseeiswhatyou geteditororsomefunkytag‐settocreateyourpagedesign,OnExpreliesonsimplehtmltags.If youhaveabsolutelynoideaabouthtml,youcanuseoursamples–butsomeofyourcolleagues willprobablygladlyhelp,afterallsomeonemusthavewrittenyourhomepage.PHPand Javascriptisnotallowedinthispages.So,hereisanexample.htmlpage.Wenameitstage1.html. stage1.html <html><head><metahttp‐equiv="Content‐Type"content="text/html;charset=utf‐8"></head> <body> <divstyle="width:100%"><divalign="left"style="width:600px;margin:auto"> <formaction="next"method="post"> <br><br> <palign="center"><b><fontsize="4">Dearparticipant–pleaseanswerthefollowingquestion:</font></b></p> variablename <center> <table> <tr><td> <inputtype="radio"name="answer"value="7">variablename<br> <inputtype="radio"name="answer"value="6">variablename<br> <inputtype="radio"name="answer"value="5"required="required">variablename<br> </td></tr> </table> </center> <palign="right"> <inputtype="submit"name="submit"value="continue"> </p> </form></div></div></center></body></html> <!‐‐ OnExpVariables: NumberOfRepetitions=10; variablename=input1.txt; ‐‐> Youcanseethatatthebottomofthepage,youinsertedacommentthattellsOnExpthatyou wantthepagetoappear10times,andyouwantthevariablename1tobereplacedbymaterial frominput1.txt.Now,OnExpwilldisplaystage1.htmlexactlytentimes,anditwillloopthrough yourinput1.txt.Everytimeitfindsanoccurrenceofvariablenameinstage1.html,itwilltakethe nextelementofinput1.txt.Thiswillproducethedesiredresult. NOTETHATYOUALWAYSNEEDTHETURQUOISEMARKEDLINESINORDERFORONEXPTOWORK.EVENIFYOU KNOWHTMLANDYOUKNOWTHAT“NEXT”ISNOVALIDACTIONFORAFORM,DON’TWORRY.ONEXPWILL KNOWHOWTOHANDLETHAT. 1.2RANDOMIZING Ofcourse,ifyouwantanexperiment,youprobablywanttohavemanyparticipantsandyou wantthemtoseeyourstimuliinarandomorder.So,whileperson1seesquestion7first,person2 couldseequestion1firstandsoon.Butofcourse,youdon’twantthespecificanswertoquestion 7toappearbelowquestion1.OnExpcandothatforyou,butyouneedtousetwoadditionaltags inyourinput1.txt.The<block></block>tagandthe<random>tag.Using<block>issimpe:you justincludeabunchofstimuliinablock,andOnExpwillthenkeepthosestimulitogether wheneverrandomizing.OnExpwillrandomizeablockifandonlyifthefirsttagthatfollowsthe <block>tagis<random>. So,forourexamplewecandothis: input1.txt <block> <random> <block> Question1 answer1q1 answer2q1 answer3q1 </block> <block> Question2 answer1q2 answer2q2 answer3q2 </block> … </block> Now,OnExpwillrandomizetheorderofquestion‐answerblocks,butwillnotchangetheorder ofquestionsandanswerswithineachblock.Assumeforinstancethatyouincludetherandom tagintothefirstquestion‐answerblock,likethis: <block> <random> Question1 answer1q1 answer2q1 answer3q1 </block> ThiswouldmakeOnExpshuffletheorderofQuestionsandanswers,soyoucouldenduphaving thequestionappearwhereananswershould. Ofcourse,youmightwanttokeeptheorderofthequestionsfixed,butyouwanttorandomize onlytheorderoftheanswersforeachquestion.Thiscanbeachievedlikethis: input1.txt <block> Question1 <block> <random> answer1q1 answer2q1 answer3q1 </block> Question2 <block> <random> answer1q2 answer2q2 answer3q2 </block> … </block> Andofcourse,youcouldwanttorandomizetheorderofthequestionsANDtheorderofthe answersforeachquestion.Thisisdoneasfollows:(notethatitmaytakesomethinkingto realizewhyweneednestedblocks). Thereisnolimitfortheembeddingofblocks.Soyoucanembedablockinablockinablockina block… input1.txt <block> <random> <block> Question1 <block> <random> answer1q1 answer2q1 answer3q1 </block> </block> <block> Question2 <block> <random> answer1q2 answer2q2 answer3q2 </block> </block> … </block> 1.3STIMULUSIDS Youdon’tneedtousestimulusIDsinOnExp.Buttherearegoodreasonstodosoandthatis relatedtothewayOnExpwillsaveyourmaterial:OnExpwillcreateone“answers”fileforeach experiment.Anditwillappendanewlinewitheverynewanswerthatischoosenbyany participant.Ofcourse,youcankeeptheparticipantsapart,sinceOnExpwillstarteverynewline withtheuniqueparticipantID.Alsoitwillsavetherelativetimetheanswerhasbeengivenwith anexactnessgoingintomicroseconds.Butwhatyouwillnotknowiswhichstimulus/question yourparticipanthasseen.Ofcourse,ifthedataisnotrandomized,youcouldreconstructthat, butitwilltakealongtime.IfyouchoosetouseIDs,however,OnExpwillsavetheIDofthe stimulustheparticipanthasseenwhenselectingtheparticularanswer. Youcanseeanexamplehere: input1.txt <id:q1>Question1</id> <id:q1‐a1>answer1q1</id> <id:q1‐a2>answer2q1</id> <id:q1‐a3>answer3q1</id> <id:q2>Question2</id> <id:q2‐a1>answer1q2</id> <id:q2‐a2>answer2q2</id> <id:q2‐a3>answer3q2</id> … Thereisonemorereasonyoumaywanttouseid‐s.Perdefault,OnExpwillassumethatevery newlineisastimulus,ifyoudon’tuseIDs.Infact,ifyouonlyusethe“opening”tagsforids,and youdon’tclosethem,OnExpwillassumethateveryendofalineisaclosingID.Butifyouhave longstimulicontainingseverallines,itmaybeusefulltoactuallyclosetheids.ThiswayOnExp willknowthatseverallinesbelongtoonlyonestimulus. ItisgoodpracticetogiveyourstimuliIDsaccordingtoyourexperimentalfactorsand conditions,suchthatyoucanimportthemeasilyintoyourstatisticsprogram. Alsonotethatifyouwanttohavenewlinesactuallyappearinthehtmlfile,youshouldusehtml tagsforthis,suchas<br/>or<p></p>etc. DON’TEVERUSETHE“”OR‘‘SIGNSINYOURINPUTFILES.THATWILLMOSTLIKELYCAUSESEVEREERRORS.IN SOMELATERVERSIONOFONEXPTHISWILLBETAKENCAREOF. 1.4SEVERALINPUTFILES ItisnotparticularlylikelythatyouwilleverneedseveralvariablesforonestageinOnExp.But it’sgoodtoknowthatyouCANhavethat,ifyouneedit.Assumeyouwantanexperiment,in whichyouwanttorandomlypairtwosetsofstimuli,say:stimulus1‐nshouldberandomly pairedwithstimulusa‐z.Itiseasytoseethatyoucannotdothiswithonlyonevariable.Insucha case,OnExpallowsyoutohavetwodistinctvariablesinonestage.Eachofthemwillcomewith theirowninputfile,whichyoucanspecify,andeveryinputfilewillbestructuredasyouplease. Thestagefilecouldlooklikethis: stage1.html <html><head><metahttp‐equiv="Content‐Type"content="text/html;charset=utf‐8"></head> <body> <divstyle="width:100%"><divalign="left"style="width:600px;margin:auto"> <formaction="next"method="post"> <br><br> <palign="center"><b><fontsize="4">Dearparticipant–pleaseanswerthefollowingquestion:</font></b></p> variablename1 <br> variablename2 <center> <table> <tr><td> <inputtype="radio"name="answer"value="7">yes<br> <inputtype="radio"name="answer"value="6">no<br> <inputtype="radio"name="answer"value="5"required="required">Idon’tknow<br> </td></tr> </table> </center> <palign="right"> <inputtype="submit"name="submit"value="Weiter"> </p> </form></div></div></center></body></html> <!‐‐ OnExpVariables: NumberOfRepetitions=10; variablename1=input1.txt; variablename2=input2.txt; ‐‐> Inthiscase,variablename1willbeseededfrominput1.txtandvariablename2willbeseeded frominput2.txt 1.5THE_NOADVANCEFEATURE. Assume,youhaveaninputfileandastage‐file.Forsomereasonyouwantastimulustoappear twiceonthesamepage.Therearetwowaystoachievethis:eitheryoudosomehardthinking andorganizeyourinputtxtsuchawaythatyoueverystimulusappearstwiceand randomizationeffectsaresuccessfullycancelled.Oryouusethe_noadvancefeature.Ifyouwrite “variablename_noadvance”intoyourstage‐file,OnExpwillnottaketheNEXTelementofyour inputfile,butthesameitusedbefore. stage1.html <html><head><metahttp‐equiv="Content‐Type"content="text/html;charset=utf‐8"></head> <body> <divstyle="width:100%"><divalign="left"style="width:600px;margin:auto"> <formaction="next"method="post"> <br><br> <palign="center"><b><fontsize="4">Dearparticipant–pleaseanswerthefollowingquestion:</font></b></p> variablename1 <br/>hereitappearsagain<br/> variablename1_noadvance <center> <table> <tr><td> <inputtype="radio"name="answer"value="7">yes<br> <inputtype="radio"name="answer"value="6">no<br> <inputtype="radio"name="answer"value="5"required="required">Idon’tknow<br> </td></tr> </table> </center> <palign="right"> <inputtype="submit"name="submit"value="Weiter"> </p> </form></div></div></center></body></html> <!‐‐ OnExpVariables: NumberOfRepetitions=10; variablename1=input1.txt; ‐‐> Inthisexample,thestimulusfromyouinput1.txtwillappeartwiceonthepage. NOTE,HOWEVER,THATIFVARIABLENAME_NOADVANCEAPPEARSBEFOREORWITHOUTVARIABLENAMEYOU GETTOTALLYUNEXPECTEDRESULTSORANERRORMESSAGE. YOUCANUSETHE_NOADVANCEFEATUREFORINSTANCETOSAVETHETEXTOFASTIMULUSINTHERESULTS FILEASIN: <FORMACTION="NEXT"METHOD="POST"> <P> VARIABLENAME </P> <INPUTTYPE="HIDDEN"NAME="TEXT"VALUE="VARIABLENAME_NOADVANCE"/> <P>IHREWEITERFÜHRUNG:<INPUTTYPE="TEXT"NAME="ANSWER"SIZE="70" AUOFOCUS="AUTOFOCUS"REQUIRED="REQUIRED"></P> <BR> <PALIGN="RIGHT"> <INPUTTYPE="SUBMIT"NAME="SUBMIT"VALUE="WEITER"> </P> </FORM> 1.6RESOURCEFILES Youcanuseresourcefiles,suchasaudio,videoorpicturefiles.Basicallythewaytousethemis verysimple:youincludethefilenames(withrespectivepathorurl)inyourinputfile,andloop throughthefilenameswithvariablename.Soforinstanceyoucandisplayasoundwith variablenameinthestage‐file andtheinputfilecouldcontainsomethinglike: <audiosrc=”http://myhomepage.com/mystimulus1.mp3”..> Notethatyoucan: a) eitheruploadyourresourcefilesontotheonexpserver.Inthiscase,youcanuserelative pathtodisplaythem.Soyoucouldsimplyhave“resources/mystimulus1.mp3”inyour inputfile b) oryoucanstorethemonsomeindependentwebsite,say,yourownhomepage,andlet thembedisplayedfromtheexternallocationusingfullurl‐sintheinputfile. ISTRONGLYRECOMMENDTHELATTERALTERNATIVE:PROBABLYYOUWILLBEUSINGANONEXPSERVERTHAT SOMEONEELSEHASSETUPANDHASALLOWEDYOUTOUSE–WHYUPLOADMBAFTERMBOFRESOURCEFILES TOHISSERVER?AFTERALL,HEMAYHAVELIMITEDBANDWIDTHTHATYOUAREUNNECESSARILYEATINGUP THISWAY. Ofcourse,youarefreetochooseyourownwayofdisplayingvideos,imagesandaudios.Youcan useflashorwhatevermethodyouwant.OnExpwillonlyreplacethevariablenamewiththe resourcefilenameyouspecifiy,andwillnotinterfereanyfurther. 1.6PROGRESSBAR Maybeyouhaveonehundredormorestimuli,youwantyoursubjecttosee.Butyouwanthimto know,howmuchisstilltocome,suchthattheydon’tquitonthepenultimateslide,being annoyedthatthisexperimentwillneverend.ForthisOnExpprovidestwoprogressbars: Thefirstoneisdisplayedonthetitlebarofthebrowser.Itlookslike“YOUR‐TITLE‐ experimentrunning.Progressi/n”. Youcandecideforeachstagefile,whetheryouwantsuchaprogressbartobeshownor not.Ifyouwantit,pleaseinclude<title></title>tagsintotheheaderofyourhtmlfile.If youdon’twantit,justdeletethe<title></title>tags.Itisassimpleasthat. Notethatsomebrowsersdonotsupportthisfeature. Thesecondoneisarealhtml5progressbar,alsoonlysupportedbysomebrowsers.To achievethisyousimplyincludethe<progress>taginsideyourstagefileatthelocation youwish.Youcanalsohaveseveralprogressbars. 1.8SEVERALSTAGES Inanexperimentyoumayneedtohavemanystages:stage1givessomegeneralinformation, stage2collectspersonaldata,stage3isforpractice,stage4isforwarm‐up,stage5isforthe actualexperimentandstage6asksforcommentsandobservations.Thiscaneasilybedonein OnExp.Allyouneedistocreateseveralstagehtmlfiles.Youwillnamethemstage1.html… stage2.htmletc.OnExpwillshoweverystageasoftenasspecifiedinthe“NumberOfRepetitions” variableoneaftertheother.So,firstitwillcompletelyfinishstage1andonlythenproceedto stage2. NOTE: EverystagehastospecifytheOnExpvariables.ATLEASTtheNumberofRepetitions.Ifyoudon’t havevariablestoreplace,youdon’tneedaninputfileeither. Everystagehastoadvanceviaa“form”.Ifyoudon’thaveaformcontainingthe“action="next"”, tag,thenextstageandeventhenextrepetitionwillnotbelinkedcorrectly.SoIadvisetocreate the“instructions”pageindependentlyofOnExporatleastincludea“proceed”buttonwith “action=”next”onit. 1.7METADATA Assumeyouneed20participantsforyourexperiment.Itmaytakeadayoracoupleofweeksto getthatnumberofparticipants.Howdoyouknowwhenyoureachedit?Simple:OnExpwill sendyouamail.Andevenmore:ifyoudothisexperimentincooperationwithsomeother people.OnExpwillsendanE‐Mailtoeveryoneinvolved. Whatyouneedtodoisthis:createafilecalled“metadata.txt”.Youincludethenumberofneeded participantsintothisfileandalltheinvolvede‐mailaddresses.Assoonasthenumberof participantsisreached,OnExpwillclosedowntheexperimentandsendoutanotificationtoall e‐mailaddresses.Themetadatafilecouldlooklikethis: metadata.txt <!‐‐ OnExpVariables: NumberOfParticipants=100; NumberOfMails=3; [email protected]; [email protected]; [email protected]; ‐‐> NOTETHATTHEMETADATA.TXTISOBLIGATORY. 1.8LATINSQUAREANDTHELIKE Now,assumethatforsomereasonyouhaveonebigexperimentinwhichyouhavetosplityour stimuliacrossparticipants.Inotherwords,youwantsomegroupofparticipantstoseeonesetof stimuli,andanothergroupofparticipantstoseeanothergroupofstimuli.Withothersoftware, youcouldsimplycreatetwoindepentendexperiments,andsendonelinktoonegroupofpeople, andanotherlinktotheothergroupofpeople.OnExpfortunatelyhelpshere. Yousimplyplaceyourstagefiles,yourstimulifilesandyourmetadatafilesforeachsub‐ experimentintoadirectory.Andyouzipallofthesedirectoriestogether.Whenyouuploadthe zip.file,OnExpwillrecognizethatithastodistributepeopleacrossthesesubexperimentsand willsimplydoit.YouonlyhavetodistributeONElinktoyourparticipants. Thisisthecorrectwaytozipyourexperiment:(theblueonesaredirectories!) experimentname.zip experiment1 metadata.txt stage1.html stage2.html stage3.html input1.txt input2.txt input3.txt experiment2 metadata.txt stage1.html stage2.html stage3.html input1.txt input2.txt input3.txt Thesearewrongwaystozipyourexperiment: Hereyouhaveembeddedyourexperiment‐datatoomuch! experimentname.zip experimentname experiment1 metadata.txt stage1.html stage2.html stage3.html input1.txt input2.txt input3.txt experiment2 metadata.txt stage1.html stage2.html stage3.html input1.txt input2.txt input3.txt Hereyouhavenotembeddedthefilesenough. experimentname.zip metadata.txt stage1.html stage2.html stage3.html input1.txt input2.txt input3.txt NOTETHATYOUWILLHAVETOEMBEDYOURSTIMULIANDSTAGEFILESUNDERADIRECTORYEVENIFYOU HAVEONLYONEEXPERIMENT.ONEXPALWAYSASSUMESMULTIPLEEXPERIMENTSANDTREATSONESINGLE EXPERIMENTJUSTASASPECIALCASE. 2.TENGOODRULESFORONEXP 1. Testyourstagefiles.Theyshouldbedisplayedproperlyinyourbrowseronyourlocal machine.Iftheyarenot,OnExpwillnotfixthem. 2. Testyourstage‐filesindependentlymanuallyreplacingthevarnameswithexactlywhat appearsbetweentheid‐sinyourstimulifile.Thiswayyoucancheckwhetherwhatyou getasaresultwilllookandfunctionthewayyouwant. 3. Neveromit“;”orclosingtags. 4. Neveruseuppercasefilenames(windowsandlinuxtreatthosedifferently,anditwill mostlikelycauseproblems). 5. Don’tusespecialcharactersinyourstimuli‐files.Usehtmlcodesinstead. 6. Don’tuse“and‘instimulifiles. 7. Checktosetthenumberofrepetitionsforeachstagecorrectly.Itmaybelowerthanthe numberofavailablestimulibutnothigher. 8. IfyourrandomizationfailsandOnExpdisplaysthewrongstimuli,youprobablygotthe blockswrong. 9. YoucantestOnExponyourlocalmachineusing“WAMPserver”. 10. Youshouldalwaystestyourexperimentonlinebeforesendingoutthelink. 3.USINGTHEONEXPSERVER 3.1UPLOADINGANEXPERIMENT Gotohttp://onexp.textstrukturen.uni‐goettingen.deandclickto“Register”.FillouttheForm andwaitforactivationbyadministrator.Afteractivationyouhavetogototheuploadpage. Enteryourusernameandyourpassword.Selectthenameofthezipfilecontainingdirectories withthesubexperiment:eachdirectorymustcontainstage‐filesandinputfiles.Ametadatafile isoptional. Submit. Ifyougetanyerrorstrytofixthefilewheretheerroroccurred.IfyouthinktheFileshouldbe [email protected]‐goettingen.dewiththeerrormessagethatoccurs.Ifyou thinkyoufoundabugpleasereportitathttp://bugs.onexp‐dev.textstrukturen.uni‐ goettingen.de. Ifyougetnoerrorssavethelinkthatyouget.Thislinkisessential,youshould a) Eitherincludethislinkintoyourinstructionpage. b) Ifyourinstructionpageisalreadyastageintheexperiment,youwillhavetosendout thewholelinktoyourparticipants. a)isthebetterandsaferoptionformostcases. Notethataftertestingtheexperiment,youshoulduploadexactlythesamezipagain,ifyouare satisfied.Thisway,youmakesure,youdon’tseeyourtest‐answersintheresultsfilesintheend. 3.2VIEWINGRESULTS Gotheresultspage.Login,andyouwillautomaticallyseeanumberofcsvfiles(ifresultsalready exist).Clickonthemandsavethemwhereveryouplease. 4.SETTINGUPYOUROWNONEXPSERVER Itispossibletocreateanownonexpserver,butaninstallerisnotyetprovided.Pleasecontact usforthedownloadlinksandsupport. DONOTCREATEANOWNSERVERIFYOUDON’TUNDERSTANDWHATTHESCRIPTSDO. PLEASELETYOURWEBMASTERDOTHATFORYOU.PUTTINGUPANONEXPSERVER WITHOUTPROPERPHPANDSERVER‐ADMINKNOWLEDGECOULDRESULTIN CATASTROPHICSECURITYISSUES! <Asteptostephowtoisunderconstruction> 5.HOW‐TOS? 5.1HOWTODISPLAYAUDIOSTIMULI: <audio src="varname" controls autoplay> Your browser does not support the audio element. </audio> 5.2HOWTODISPLAYRADIOBUTTONS <inputtype="radio"name="answer"value="7">yes<br> <inputtype="radio"name="answer"value="6">no<br> <inputtype="radio"name="answer"value="5"required="required">Idon’tknow<br> NotethatyouneedtohavetheSAME“name”foreachbutton.Onlythevaluewillbesaved. 5.3HOWTOINCLUDETHEINSTRUCTIONFILEASASTAGE: Thetrickistohaveasimpleformandnovariables: Yourinstructions <formaction="next"method="post"> <inputtype="submit"name="submit"value="start"> </form> <!‐‐ OnExpVariables: NumberOfRepetitions=1; ‐‐> 5.4HOWTOREPORTBUGS,REQUESTSANDTOHELPDEVELOPING. Ifyouwanttohelpusdevelopingthissoftwareyoucanhelpuswithbugreports,wishlistsor yourdevelopingskills. Wecreatedadevelopingserverunderhttp://onexp‐dev.textstrukturen.uni‐goettingen.dehere youcanfindtheactualrevisionofthesoftware.Hereitispossiblethatthesoftwareisnotstable. Fordocumentationweusehttps://trac.onexp‐dev.textstrukturen.uni‐goettingen.de.The revisionsarestoredinsubversionhttps://svn.onexp‐dev.textstrukturen.uni‐goettingen.de.If [email protected]‐goettingen.de. Yes,youareallowedtochangeandredistributeOnExp,butalwaysincludealinktotheofficial homepage. Ifyouareadeveloperandyoucreatedsomemorefeatures,pleaseletmeknow.Wemight includeitintheofficialdistribution. 6.OTHERNOTES 1.BeawareofpotentialnetworklagsifyouwanttodoexperimentswithOnExpinwhichtime playsacrucialrole.Thisisespeciallyproblematic,ifyouhavelargepicturefilesoraudiostimuli, astheirloadtimemayvaryfromrepetitiontorepetition.Ifyouhavesimpletextstimuli,thelag maynotberelevantafterall. 2.IfanyonewantstodosomeserioustestingontheuseageofOnExpfortimedexperiments,I wouldliketoknowtheresults. Copyright©EdgarOnea,2011. ThankstoAlexanderSyringforlotsofhelpinthedevelopmentofOnExp.