Hi On Tue, 5 Mar 2002, Claudia Stanny wrote: > Does SPSS have a mechanism by which I can verify the accuracy of a large > SPSS data file by creating two independent versions of the file and > comparing them?
I think it would help if you explained exactly what you mean by "creating two independent versions of the file." Do you mean: (1) Having the data entered twice? (2) Entering the data once, and then making a copy of the file electronically? (3) Something else? There would seem to be no reason to expect differences for (2). So presumably (1) or (3) are what you mean? > We plan to compute and compare descriptive statistics > computed for each variable for the two independent versions of the data, > but this will only those identify variables with data discrepancies. Is > there a procedure for doing a cell-by-cell parity comparison and identify > cells in the two files that have different entries? I am looking for a > procedure that will do what keypunch operators used to do -- verifying the > accuracy of punched cards by repunching them. SPSS does have a DO REPEAT command that allows users to do things like compare a list of variables. It would perhaps work something like this: DO REPEAT v1 = a1 TO a30 /v2 = b1 TO b30 /r = r1 TO r30 COMPUTE r = v1 EQ v2 END REPEAT Examining variables r1 to r30 will show discrepancies between a1-b1, a2-b2, and so on (values will be 0 for non-matches and 1 for matches). To do this, you will also need to get SPSS to read both files and match the corresponding records to make a single working file before making the comparisons. There is also an SPSS newsgroup that is VERY helpful with such problems. Its name is: comp.soft-sys.stat.spss Best wishes Jim ============================================================================ James M. Clark (204) 786-9757 Department of Psychology (204) 774-4134 Fax University of Winnipeg 4L05D Winnipeg, Manitoba R3B 2E9 [EMAIL PROTECTED] CANADA http://www.uwinnipeg.ca/~clark ============================================================================ --- You are currently subscribed to tips as: [EMAIL PROTECTED] To unsubscribe send a blank email to [EMAIL PROTECTED]
