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									IMPLICIT ATTITUDE TEST - NEED FOR AFFILIATION with images
SCRIPT INFO

Main Inquisit programming: Sean Draine (seandr@millisecond.com)
last updated:  04-19-2017 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Script Copyright © 04-19-2017 Millisecond Software


BACKGROUND INFO

The Implicit Association Task (Greenwald, McGhee, & Schwartz, 1998) is a widely-used cognitive-behavioral paradigm
that measures the strength of automatic (implicit) associations between concepts in people’s minds relying 
on latency measures in a simple sorting task.
 
The strength of an association between concepts is measured by the standardized mean difference score of 
the 'hypothesis-inconsistent' pairings and 'hypothesis-consistent' pairings (d-score) (Greenwald, Nosek, & Banaji, 2003). 
In general, the higher the d-score the stronger is the association between the 'hypothesis-consistent' pairings 
(decided by researchers). Negative d-scores suggest a stronger association between the 'hypothesis-inconsistent' pairings.

Inquisit calculates d-scores using the improved scoring algorithm as described in Greenwald et al (2003). 
Error trials are handled by requiring respondents to correct their responses according to recommendation (p.214).

D-scores obtained with this script:
Positive d-scores: support a stronger association between 'Together-Attractive' and 'Alone- Not attractive' than for the opposite pairings
Negative d-scores: support a stronger association between 'Alone-Attractive' and 'Together-Not attractive' than for the opposite pairings

References:
Greenwald, A. G., McGhee, D. E., & Schwartz, J. K. L. (1998). Measuring individual differences in implicit cognition: 
The Implicit Association Test. Journal of Personality and Social Psychology, 74, 1464-1480.

Greenwald, A. G., Nosek, B. A., & Banaji, M. R. (2003). Understanding and Using the Implicit Association Test: 
I. An Improved Scoring Algorithm. Journal of Personality and Social Psychology, 85, 197-216.


											  *Task*
Participants are presented either adjectives or pictures (one by one) and are asked 
to do a simple categorization task to categorize the items into  categories like 
"Attractive OR Together" vs. "Not attractive OR Alone" by pressing 2 different
keys on the keyboard.



DATA FILE INFORMATION: 
The default data stored in the data files are:

(1) Raw data file: 'AffiliationNeedIAT_raw*.iqdat' (a separate file for each participant)

build:							Inquisit build
computer.platform:				the platform the script was run on
date, time, subject, group:		date and time script was run with the current subject/groupnumber 
										Note: group1/group2 counterbalance the order in which the pairings are run
blockcode, blocknum:			the name and number of the current block
trialcode, trialnum: 			the name and number of the currently recorded trial
									(Note: not all trials that are run might record data; by default data is collected unless /recorddata = false is set for a particular trial/block) 
response:						the final trial response (scancodes of the keys pressed)
										Note: script saves the final and -by design- correct response
correct:						the accuracy of the initial response
										0 = initial response was incorrect and needed to be corrected
										1 = initial response is correct
latency:						the latency of the final (correct) response in ms
stimulusnumber:					the number of the current stimulus
stimulusitem:					the currently presented item
expressions.da:					d-score of the first short blocks
expressions.db:					d-score of the second long blocks
expressions.d:					overall d-score(non-weighted mean of the 2 d-scores)
/ percentcorrect:       		the overall percent correct score of initial responses of test trials of D-score qualifying latencies

(2) Summary data file: 'AffiliationNeedIAT_summary*.iqdat' (a separate file for each participant)

script.startdate:				date script was run
script.starttime:				time script was started
script.subjectid:				subject id number
script.groupid:					group id number
script.elapsedtime:				time it took to run script (in ms)
computer.platform:				the platform the script was run on
/completed:						0 = script was not completed (prematurely aborted); 1 = script was completed (all conditions run)
expressions.da:					d-score of the first blocks
expressions.db:					d-score of the second blocks
expressions.d:					overall d-score
/ percentcorrect:       		the overall percent correct score of initial responses of test trials of D-score qualifying latencies



EXPERIMENTAL SET-UP

Hypothesis-consistent pairings vs. hypothesis-inconsistent pairings; tested within-subjects 
=> order is counterbalanced by groupnumber assignment

Block Sequence:
1. Target Category sorting training
2. Attribute sorting training
3. 1. Test Block of hypothesis-consistent* pairings with 20 trials (half the participant start with inconsistent pairings)
4. 2. Test Block of hypothesis-consistent pairings with 40 trials
5. Target Category sorting training with targets switching sides
6. 1. Test Block of hypothesis-inconsistent pairings with 20 trials
7. 2. Test Block of hypothesis-inconsistent pairings with 40 trials

In all Test Blocks:
* attributes and targets alternate
* attributes as well as targets are randomly selected without replacement

Trial Sequence:
Target -> until correct response -> ISI: 250ms (default)-> Target....STIMULI
Stimuli can be edited under section Editable Stimuli

INSTRUCTIONS

* start instruction page is provided as an html page. It automatically adapts to different images and category labels UNLESS
the number of attributes and/or targets have been changed. In this case, changes have to be 
made to file "intro_iat.htm", so that the correct number of items are presented in the overview table.

Example: instead of 8 words for target A, only 5 should be presented:

in file "intro_iat.htm":
change:
			<%item.targetA.item(1)%>, <%item.targetA.item(2)%>, <%item.targetA.item(3)%>, <%item.targetA.item(4)%>, 
				<%item.targetA.item(5)%>, <%item.targetA.item(6)%>, <%item.targetA.item(7)%>, <%item.targetA.item(8)%>
			

To:
			<%item.targetA.item(1)%>, <%item.targetA.item(2)%>, <%item.targetA.item(3)%>, <%item.targetA.item(4)%>, 
				<%item.targetA.item(5)%>
			

* item.instructions under section 'Editable Instructions' contains the the trial instructions
The instructions adapt automatically if different attributes and targets are used.


EDITABLE CODE:
check below for (relatively) easily editable parameters, stimuli, instructions etc. 
Keep in mind that you can use this script as a template and therefore always "mess" with the entire code to further customize your experiment.

The parameters you can change are:

/showsummaryfeedback:		set parameter showsummaryfeedback = true to display summary feedback to participants at the end (default)
							set parameter showsummaryfeedback = false if no summary feedback should be presented to participants
/ISI:						interstimulus interval (in ms) (default: 250ms)
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