Scoring the IAT (case 12779)

[balford@work]

I'm looking for guidance in scoring an IAT, e.g., the IAT-Race demo experiment provided by Empirisoft. Anybody that cannot provide guidance I'd greatly appreciate it!

[jarvis24]

[the following reply is taken from a summary post to the SPSP mailing list by Joseph Comeau]
Hi to all of you who were interested in the DirectRT IATs and how to score them. below are the responses I got. thanks to the contributers.
Joseph Comeau

[jarvis24]

[the following edited reply is taken from a summary post to the SPSP mailing list by Joseph Comeau]

I am sure you will get a lot of replies but if you don't, call me and i will walk you through easily changing the Inquisit syntax to work with Direct RT (all you need to do is transform the variables so they are named the same as in the syntax and check a couple of procedural things in your direct rt program). My cell is *** (I am a post doc of Mahzarin Banaji's).

This all assumes that you programmed and collected data using a 7-block IAT

1. Merge all of your DirectRT files with the filemerge software that Blair Jarvis (from Empirisoft) that comes included with DirectRT (save the merged file as ".csv" -- it will pull into SPSS much better than .txt).
2. Pull the big huge file into SPSS.
3. In DirectRT, your trial #rs must begin with #1 (and go to whatever). SO: if the range in DirectRT is 5-380, you need to transform it to range from 1-376.
4. In DirectRT, your block numbers need to range from 1-7 (i recall default coding the blocks 0-6 so you will want to transform the numbers to range from 1-7)
5. In DirectRT your errors vs correct responses may have been coded
   differently than the syntax needs. Your errors must be coded = 0 and correct responses = 1
6. A critical issue is one of IAT order. the IAT syntax thinks you ran all odd subjects as order #1 (e.g., black+bad & white+good) and all even subjects as order #2 (e.g., black+good & white+bad; see syntax from the IAT SPSS syntax below).
7. In the syntax file, you MUST change the order variable syntax or compute an appropriate "order variable" in your SPSS data file and then remome the part of the syntax that looks like this:
   
   

   *If order of the combined
   tasks differs in some other fashion, provide an appropriate replacement
   * for the following line (which works when order differs for odd and even
   subject numbers) .
   COMPUTE ORDER = mod(subj, 2) .
   RECODE ORDER (0=2) .

8. Regardless of what DirectRT named your variables, there are 5 key variables that the SPSS IAT syntax needs to read in order to
   run. SO: you will want:
   
   

   subject variable to become --> subj
   block variable --> block
   trial variable = trial
   response time variable = lat 
   correct response variable = cor

9. You do not need to rename anything else (looking at the syntax, you may
   think you need to add additional stuff in there... you can, but it doesn't
   affect how the syntax runs and is not necessary).
10. Attached is an SPSS IAT scoring syntax file to use.
11. After running for a minute or so (you will see a bunch of SPSS files opening and closing) the output of the syntax file will be a file with a bunch of variables in it. The variables you really want to use are: D600 (in DirectRT you must add the "error penalty" in the scoring; see Greenwald et al., 2003 for an explanation). the other D variables you may wish to look at are the practice600 and the test600 (which will separate your IAT score into the practice blocks vs. the test blocks). You may also wish to look at the overall errors-- if any person has 35% or more errors, you shouldn't use their data.
12. The direction of your scored IAT variable is determined by how you
    programmed the experiment. Assuming you changed the ORDER variable as indicated above, the syntax scores everything to conform to blocks 3&4 minus blocks 6&7 (and, of course, smaller numbers here mean faster responding).
    
    This should give you all you need after a good reading of Greenwald et al.'s scoring algorithm paper. Good luck!!!

Dana R. Carney, Ph.D.
Department of Psychology
Harvard University

Note: Attached is the basic IAT syntax from Tony Greenwald's site with some variable recode syntax at the top (I made some notes for the user, also). I actually used this syntax for my own data and I am pretty sure my instructions are correct (I have had to do this a few times but differently each time as I am usually helping someone else and everyone programs differently).

[jarvis24]

[the following edited reply is taken from a summary post to the SPSP mailing list by Joseph Comeau]

Hello there,
Well this may be your lucky day! I have been using DirectRT to present several fully counterbalanced race-iats to kids in grades 1-5 (aka ch'iat, developed by Andrew Baron and Mazarin Banaji). I use SAS to import and analyze the data, and it works very well indeed. I can go from the Excel output files to SAS analysis in a matter of 30 minutes. If this is helpful to you let me know.

Barry Corenblum
Department of Psychology
Brandon University

[balford@work]

If this is the kind of help I can expect from Empirisoft and DirectRT users I am quite impressed!

I am a SAS junkie, so I'd love to know the procedure and code, if you're willing to share.

Thank You!

[jarvis24]

Caught me on a good day, I guess I've contacted the user who wrote the response about SAS. If/when I hear back, I'll post the SAS code if I can get my hands on it.

[slaurent]

First off, thanks for all the work in creating, adapting, and modifying this syntax, and posting it for all to use!

That said, I have a question about the syntax you posted (the referenced post is shown below). Because I have a more complex coding scheme than even #ed Ss = order 1 (e.g., white + good first) and odd Ss = order 2, I merged all files from each separate order together rather than merging both orders together. In effect, it is as if I have not counterbalanced order (I have, but I will deal with this in another way) - and thus, in each merged file there is a single order of presentation. Does anyone out there know of an easy fix to the syntax so that SPSS will NOT assume that I have different orders for odd and even #ed Ss when computing the D statistics? I'm not sure what part I need to take out. It seems as if it should be simple, but in fact, the syntax is rather complex in places and I'm not sure what part needs to be changed.

Thanks!

[QUOTE=jarvis24;2239][the following edited reply is taken from a summary post to the SPSP mailing list by Joseph Comeau]

I am sure you will get a lot of replies but if you don't, call me and i will walk you through easily changing the Inquisit syntax to work with Direct RT (all you need to do is transform the variables so they are named the same as in the syntax and check a couple of procedural things in your direct rt program). My cell is *** (I am a post doc of Mahzarin Banaji's).

This all assumes that you programmed and collected data using a 7-block IAT
[LIST=1][*]Merge all of your DirectRT files with the filemerge software that Blair Jarvis (from Empirisoft) that comes included with DirectRT (save the merged file as ".csv" -- it will pull into SPSS much better than .txt).[*]Pull the big huge file into SPSS.[*]In DirectRT, your trial #rs must begin with #1 (and go to whatever). SO: if the range in DirectRT is 5-380, you need to transform it to range from 1-376.[*]In DirectRT, your block numbers need to range from 1-7 (i recall default coding the blocks 0-6 so you will want to transform the numbers to range from 1-7)[*]In DirectRT your errors vs correct responses may have been coded
differently than the syntax needs. Your errors must be coded = 0 and correct responses = 1[*]A critical issue is one of IAT order. the IAT syntax thinks you ran all odd subjects as order #1 (e.g., black+bad & white+good) and all even subjects as order #2 (e.g., black+good & white+bad; see syntax from the IAT SPSS syntax below).[*]In the syntax file, you MUST change the order variable syntax or compute an appropriate "order variable" in your SPSS data file and then remome the part of the syntax that looks like this:

[code]*If order of the combined
tasks differs in some other fashion, provide an appropriate replacement
* for the following line (which works when order differs for odd and even
subject numbers) .
COMPUTE ORDER = mod(subj, 2) .
RECODE ORDER (0=2) .

[Goldenrude]

Being a total newbie to the IAT, i was wondering if anyone had a single IAT SPSS syntax to share ? I just used a single IAT in one of my experiment and i now need to look at the data and to be quite honest i don't know what to do

[padennis]

Being a total newbie to the IAT, i was wondering if anyone had a single IAT SPSS syntax to share ? I just used a single IAT in one of my experiment and i now need to look at the data and to be quite honest i don't know what to do

I'm all about posting ridiculously late responses right now. Hopefully this helps someone!

BTW, this is based on Greenwald, Nosek, and Banaji's (2003) scoring algorithm.

[sbvick]

Thanks so much for posting the spss syntax to score the IAT using DirectRT data. My one question is about the format of the data file that works with this syntax. Does it assume that the file is organized such that each row of data represents one case (participant) or does it read the file as it is recorded within DirectRT (multiple rows per case)?

If it is the former, I could use some guidance as to how to transform the files. I've looked at the description in the DirectRT Help menu but I find it rather vague. Does anyone have an example of spss syntax you've used to transform the file and/or a data file that shows how this DirectRT IAT data is supposed to look before it is scored? I'm working with the 2006 version of DirectRT (I believe).

[jarvis24]

I don't but maybe one of our users could comment on this?

[jarvis24]

[edited from support email]

I was wondering if you could confirm whether when running an IAT on DirectRT if it records the response time with a built in error. That is, if a participant hits the incorrect response key (makes an error) does that reaction time get recorded, or does the reaction time captured by the program continue until the correct response key is hit?

The recorded response time is that of the correct answer--as measured from the start of the trial (i.e., stimulus onset).

[melmarie32]

Does anyone have SPSS syntax to score the Direct RT race IAT when only the test trials are recorded?

[Jomo]

Hi guys, I am stuck

I am getting negative d 600 scores, is this normal? Any help will be welcome

[js2013]

Does anyone know a normal range for d scores? I was under the impression that they should be relatively small, and mine are pretty large. Can anyone help me or at least point me in theright direction? Thanks so much.