D-Score Calculations

Lauren Simon

unread,

Aug 3, 2021, 5:28:17 PM8/3/21

to Yoav Bar-Anan, min...@googlegroups.com

Hi Yoav,

I'm working with a client who wants to know why the d-scores and feedback provided by our IAT online differ from the scores we calculated for her. I explained that we recommend using the scores we calculate because they are more accurate than what the site provides, but could you provide any more information about how the website creates d-scores and IAT feedback?

Best,

Lauren
--

Lauren Simon, B. A. (she/her)

Special Projects Coordinator

Project Implicit, Inc.

MSW Candidate at Columbia University

Project Implicit will be closed 7/26-7/30

Yoav Bar-Anan

unread,

Aug 4, 2021, 5:06:28 AM8/4/21

to Minno.js

Hi Lauren,

Indeed, it is not recommended to use the IAT score computed with our IAT extension for research. The IAT extension's scoring is slightly different than the recommended, for considerations (I don't fully remember) that are related to the feedback to participants.

The IAT D score in the recommended scoring algorithm is the average of two IAT scores: one computed from Blocks 3 and 6, and one from Blocks 4 and 7. The IAT extension's scoring computes only one score, from all the blocks.

In other words, the extension's D = [(mean latency in blocks 6 and 7) - (mean latency in blocks 3 and 4) / (Standard deviation in blocks 3,4,6,7)]

The recommended D = {[(mean latency in Block 6) - (mean latency in Block 3 ) / (Standard deviation in Blocks 3&6)] + [(mean latency in Block 7) - (mean latency in Block 4) / (Standard deviation in blocks 4,7)]}/2

In addition, before computing the mean latency in the extension, we delete all trials with latency above 10000 and below 400, and we replace the latency of error trials with the [mean latency of that blocks + 600]. We do not provide feedback for participants who had at least 10% of trials with latency below 150ms.

Yoav

Assaf Suberry

unread,

Oct 4, 2021, 3:55:45 AM10/4/21

to Minno.js

Yoav, Thank you

This answer is useful. Can you please provide the D score calculation method for the Brief-IAT

As the no. of blocks is different

Thank you

Assaf

ב-יום רביעי, 4 באוגוסט 2021 בשעה 12:06:28 UTC+3, Yoav Bar-Anan כתב/ה:

Mayan Navon

unread,

Oct 4, 2021, 4:10:39 AM10/4/21

to Assaf Suberry, Minno.js

Hi Assaf,

I recommend you read the paper that introduced the Brief-IAT. It explains how to calculate the D score in this modified measure.

Reminder: this group is meant to provide technical support for users of minno.js, rather than professional help with attitude measurement using indirect measures in general.

Best,

Mayan

--
You received this message because you are subscribed to the Google Groups "Minno.js" group.
To unsubscribe from this group and stop receiving emails from it, send an email to minnojs+u...@googlegroups.com.
To view this discussion on the web visit https://groups.google.com/d/msgid/minnojs/5f8f5dd2-a49b-41e6-9fb1-4df21d6b7e37n%40googlegroups.com.