Hi,
I've got D score SPSS data from using the syntax script for the Brief IAT with pictures and was wondering why there are D scores and Inquisit D scores. Why are there two sets of D scores?
As you certainly noticed, the Inquisit scripts calculate D scores automatically and write them to the data file. You may compare those automatic calculations to those provided by SPSS as a consistency check.
Thank you for your reply. The absolute values are the same between the two sets but the SPSS D scores have come out as negative and the Inquisit D scores have come out as positive. Is this supposed to happen?
No. Check your SPSS syntax, presumably the block order is not determined correctly. You must make sure it's determined by the group id, not the subject id.
Hi, sorry I cannot figure out which part of the syntax file that problem refers to. I just ran the syntax script on some data from the original brief IAT with pictures from this website and the same problem seems to occur as well- the negative or positive sign just seems to be the opposite between the two sets of D scores. What part of the syntax script do I change? Thanks.
Lines 33-34
IF (MOD(subject,2) = 1) Order = 1 .IF (MOD(subject,2) = 0) Order = 2.
If you used any of the BriefIAT scripts *for Inquisit 4*, block order is not determined by subject id, but by group id.
Thanks. I used the inquisit 3 brief IAT with pictures script but then had to download the inquisit 4 trial because inquisit 3 expired halfway through so I have all the results now using Inquisit 4. Does this make any difference?
Yes, the script version you used makes a difference. The Inquisit 3 BIATs rely on subject id to determine block order, the corresponding Inquisit 4 scripts rely on group id. Which Inquisit version you used to collect data does not matter.
So doesn't that mean that I shouldn't be seeing a difference between the negative or positive signs on the D scores calculated by SPSS and the Inquisit D scores?
Yes, you should not see any difference. You'll want to work through both the Inquisit script and the SPSS syntax to check where the discrepancy stems from.