If your data file is small, it is easiest merely to have it at the end of your control file. If your data is extensive, keep it in a separate data file.

Your data file is expected to contain a record for each person containing a person-id field and a string of responses to some items. Your data can be placed either at the end of your control file or in a separate disk file.

 

WINSTEPS reads up to 30 columns of person-id information as standard. Normally the person-id is assumed to end when the response data begin or when the end of your data record is reached. However, an explicit length of up to 300 characters can be given using the NAMLEN= control variable.

 

By the term "response" is meant a data value which can be a category label or value, score on an item or a multiple-choice option code. The responses can be one or two characters wide. Every record must contain responses (or missing data codes) to the same items. The response (or missing data code) for a particular item must be in the same position in the same format in every record. If every person was not administered every item then mark the missing responses blank or make them some otherwise unused code, so that the alignment of item responses from record to record is maintained.

 

A table of valid responses is entered using the CODES= character string. Any other response found in your data is treated as missing. By using the CODES=, KEYn=, NEWSCORE= and IVALUE= options, virtually any type of response, e.g. "01", "1234", " 1 2 3 4", "abcd", " a b c d", can be scored and analyzed. Missing responses are usually ignored, but the MISSCORE= control variable allows such responses to be treated as, say, "wrong".

 

When writing a file from SPSS, the syntax is:

FORMATS ITEM1 ITEM2 ITEM3 (F1). i.e., FORMATS varlist (format) [varlist..]

The procedure is FORMATS and then the variable list. Enclosed in parentheses is the format type. F signifies numeric while 1 signifies the width. (F2) would signify a numeric with a width of 2 columns for XWIDE=2. See pages 216 and 217 of the SPSS Reference Guide (1990). See also the SPSS pull-down menu.