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Cleaning IAT Data in SPSS

https://forums.millisecond.com/Topic19604.aspx

By Juanp - 8/29/2016

Hello everyone,

I was able to extract my IAT data to excel and then to SPSS, but I now have data from each participant for each trial. Thus, I was wondering if there is any way that I could “clean” it/merge it to make the data analyzable.
In case your wondering why I used excel, it was because I was unable to successfully use the SPSS syntax. That leads me to another possible issue.

1. Regarding my IAT: The number of attributes and labels were not changed. However, I did change the number of pictures (item target a and item target b). With this in mind, I was hoping that I did not alter any sequence. Specifically, I had 20 pictures in target A and 20 pictures in target B.

Any advice would be greatly appreciated!

Juan
By Dave - 8/29/2016

#1: If you used any of the IAT templates from the Inquisit Test Library, you do not need to clean up or aggregate raw data in SPSS. The scripts automatically compute D-scores and write those to both the raw-data as well as the single-line summary data files. The latter are readily analyzable.

#2: There is SPSS aggregation syntax for raw data files available on the library's IAT page. You'll need to work through the syntax, understand it and may have to adapt it to run on your system / in your SPSS version. You should pay particular attention to how your IAT script(s) assigned between-subjects conditions (i.e., the block order -- compatible vs incompatible first). The SPSS syntax assumes that was done by subject number, whereas the newer Inquisit IAT templates use the group number instead.

#3: For a general introduction on aggregating raw data, work through the following resources:

- Lacroix & Giguère (2006) available athttp://www.tqmp.org/Content/vol02-1/p020/p020.pdf
- https://computingforpsychologists.wordpress.com/2012/12/11/how-to-analyse-reaction-time-rt-data-part-1/
- http://ron.dotsch.org/importing-inquisit-data-files-into-spss-pasw/
- http://jeromyanglim.blogspot.de/2010/07/how-to-process-inquisit-raw-data-in.html

#4: The number of items in attributes and targets doesn't matter / doesn't make any difference with regards to analyzing the data.
By Juanp - 8/29/2016

Thank you for the clarification and recommendations Dave. I will work on reading the aforementioned resources and hope to solve this. 

Best,
Juan