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Download EViews 5.1 User's Guide - FOBTECH Remote Services
Transcript
Creating a Link—193 converted into ordinary series at any time. Once a series is created, however, it may not be converted back into a link. Match merge options Whether you elect to create a new series with fixed values or to create a new link series, you must specify link options. Match ID information First, you must specify the information that EViews will use to identify matches between observations in the two pages. In the Source ID and Destination ID edit fields, you will enter the names of one or more source ID series and one or more destination ID series. The number and order of the names in the two fields should match. Thus, if you wish to match both CXID1 and PERIOD1 in the source page to CXID2 and PERIOD2 in the second page, you should enter the sets of names in parallel. Here, we choose to match observations using the values of the STATE1 series in the source page and the values of the STATE2 series in the destination page. Next, there is a checkbox labeled Treat NA as ID category for whether to use observations which have NA values in the source and destination ID values. By default, observations are ignored if there are NAs in the ID series; by selecting this option, you instruct EViews to match observations with NA ID values from the source page to observations with NA ID values in the destination page. Link calculation settings The remaining options are used when computing the link values. First, you should specify a source series contraction method. As described in “Linking by general match merging” on page 178, the first step in every match merge is to perform a contraction to ensure uniqueness of the source values. Since contraction is always performed, you should pay attention to your contraction method even when the source IDs are unique, since some settings will not yield the original source data. There is an extensive list of contractions from which you may choose. For links involving numeric series you may choose to employ obvious methods such as the Mean (default) or the Median of the observations, or less obvious summary statistics such as the Variance, Kurtosis, Quantile, Number of obs, or Number of NAs. For links involving alpha series, you must select from a subset of the numeric contractions: Unique values (default) , No contractions allowed, First, Last, Maximum, Minimum, Number of obs, Number of NAs.
