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									DICTATOR GAME
SCRIPT INFO

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 10-22-2012
last updated: 01-08-2016 by K.Borchert (katjab@millisecond.com) for Millisecond Software LLC

Copyright © 01-08-2016 Millisecond Software


BACKGROUND INFO

											*Purpose*
This script implements the Dictator Game as described in:

Brocklebank, S., Lewis, G.J, & Bates, T.C. (2011). Personality accounts for stable preferences and expectations 
across a range of simple games. Personality and Individual Differences, 51, 881-886.


											  *Task*
A participant (= Player B) gets to allocate money (resources) that is presented in a decision tree format to another Player A and herself. 
Participant (Player B) has the choice to allocate the money in a more or less "prosocial" manner. 


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

(1) Raw data file: 'DictatorGame_raw*.iqdat' (a separate script 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 
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) 
/leftAvalue-rightBvalue:		contain the designated 'left' and 'right' value amounts for player A and player B
									!!! these amounts can appear on the left OR right of the decision tree
values.responsebranch:			the actual branch selected (B1 or B2)

stimulusitem:					the presented stimuli in order of trial presentation
response:						the participant's response
									Note: the selection of the designated 'left' or 'right' amounts
									(e.g. if the designated 'left' amounts are always the prosocial choice, response
									would reflect the nature of the choice rather than the tree branch whereas
									values.responsebranch reflects the actual tree branch selected)

correct:						the correctness of the response
latency: 						the response latency (in ms)
/count_left:					sums up all designated 'left' choices
/count_right:					sums up all designated 'right' choices
/totalA:						the total amount Player A owns
/totalB:						the total amount Player B owns

(2) Summary data file: 'DictatorGame_summary*.iqdat' (Inquisit Lab: one data file per 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; 1 = script was completed (all conditions run)
/show_opponentpic:				1 = a picture of an opponent is displayed on decision tree screen (fine tune picture under STIMULUS -> picture.Opponent]
								0 = no opponent picture is displayed (default)
/showPlayerAwins:				1 = show win status of Player A; 0 = do not show win status of player A (default)
/showPlayerBwins:				1 = show win status of Player B; 0 = do not show win status of player B (default)
/posttrialpause:				sets the posttrialpause (default = 1000ms)
/count_left:					sums up all designated 'left' choices
/count_right:					sums up all designated 'right' choices
/totalA:						the total amount Player A owns
/totalB:						the total amount Player B owns


EXPERIMENTAL SET-UP
	
1) Number of Games Run:
This script runs 6 dictator game trials (default).

NOTE: to change the number of games played, edit
a) LISTS: list.lefta, list.leftb, list.righta, list.rightb to reflect the desired number of trials/amounts
b) BLOCK: adjust the number of trials run under block.dictator

2) Amounts:
The  designated 'left' and 'right' amounts allocated are stored in list.leftA, list.leftB,
list.rightA and list.rightB. The default amounts provided in this script are the ones used by Brocklebank et al (2011).
Designated 'left' = amounts that Brocklebank et al (2011) report to be the 'left' amounts in table 1.
(in this particular script, the designated 'left' responses could be interpreted as the more "prosocial" choices)

The amounts can be easily adapted by each experimenter. Furthermore, by default the amounts are presented in a 
sequential order for each participant. To change presentation to random, go to LISTS-> list.leftA and follow instructions.

3) Within-participant control of response keys:
Presentation of designated 'left' amounts randomized without replacement within participants.
Of the 6 games (default), 3 randomly determined trials will display the designated 'left' choices on the left branch, 
the remaining 3 will display them on the right branch.
!!!NOTE:
=> values.responsebranch reflects the actual branch chosen by the participant.
=> 'Response' reflects if participant chose the designated 'left or 'right' amounts 

STIMULI
optional opponent pics -> see section Editable Stimuli

INSTRUCTIONS
Instructions can be edited under Editable Instructions

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:

/pictureintro = 0				1 = a separate picture introduction of the co-player is displayed before decision tree screens come up
								(fine tune picture under STIMULUS -> picture.opponentpic]
								0 = no separate picture introduction of the co-player (default)
/show_opponentpic:				1 = a picture of an opponent is displayed on decision tree screen (fine tune picture under STIMULUS -> picture.Opponent]
								0 = no opponent picture is displayed (default)
/showPlayerAwins:				1 = show win status of Player A; 0 = do not show win status of player A (default)
/showPlayerBwins:				1 = show win status of Player B; 0 = do not show win status of player B (default)
/posttrialpause:				sets the posttrialpause (default = 1000ms)


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