User Guide for the TIMSS International Database.pdf - TIMSS and ...

P E R F O R M I N G A N A L Y S E S C H A P T E R 9
The filenames in SAS and SPSS have been kept constant, except for the last three characters
of the file name. As defined previously in Table 7.14, four files are included to provide
control code to perform the recodes of the test items in the written and performance
assessment in Populations 1 and 2:
• Written Assessment Files (ASASCORE, BSASCORE)
• Performed Assessment Files (ASPSCORE, BSPSCORE)
When using this code, the user must first consider the recoding scheme that is desired. For
example, under certain circumstances the user might want to recode the not reached responses
as incorrect (codes 6 and 96), whereas under other circumstances the user might want to
recode these responses as not administered or invalid. In the case of TIMSS, not reached
responses were recoded as not administered (and effectively as missing responses) for the
purpose of calibrating the items when setting the international scale. But the not-reached
responses were then recoded as incorrect when scoring the item for the individual countries,
and for the purpose of calculating the scale scores for the individuals. By default, the scoring
program provided with the database recodes the items coded as not reached and those left
blank coded as incorrect responses.
To use these macros the user needs to include them as part of the SAS or SPSS programs
used for the analysis. This is done by using the INCLUDE statement in the corresponding
program. In the case of SAS, the scoring program code should be included as part of a
DATA step that reads the items that are to be recoded. When using SPSS, the scoring program
code should be included after the system file containing the item responses has been read into
memory and becomes the working file. Both of these programs recode the items onto
themselves so, if the user want to preserve the original answers and codes assigned to the
questions, then the file with the recoded item variables needs to be saved under a different file
name. A copy of the macro that scores the items in SAS and SPSS and an example of how it
is invoked in presented in Figure 9.21 and Figure 9.22.
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