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							*SOCIAL ECONOMIC GAMES: DICTATOR GAME*
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
Date: 10-22-2012
last updated:  12-11-2019 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © 12-11-2019 Millisecond Software

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BACKGROUND INFO 	
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This script implements the Dictator Game, a socio-economic game about the allocation of monetary
resources. In the Dictator Game participants get the choice to allocate money in either a more pro-social 
or less pro-social manner without having to take a possible response/revenge of their opponent into account.

The implemented procedure is based on:

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.


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TASK DESCRIPTION
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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. 

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DURATION 
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the default set-up of the script takes appr. 3 minutes to complete

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

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

build:								The specific Inquisit version used (the 'build') that was run
computer.platform:				the platform the script was run on (win/mac/ios/android)
date, time, 						date and time script was run 
subject, group, 					with the current subject/groupnumber
script.sessionid:					with the current session id

blockcode, blocknum:			the name and number of the current block (built-in Inquisit variable)
trialcode, trialnum: 				the name and number of the currently recorded trial (built-in Inquisit variable)
										Note: trialnum is a built-in Inquisit variable; it counts all trials run; even those
										that do not store data to the data file.
										
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
									
responsebranch:					the actual branch selected (B1 or B2)

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)

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 wins
totalB:							the total amount Player B wins

(2) Summary data file: 'dictatorgame_summary*.iqdat' (Inquisit Lab: one data file per participant)

computer.platform:				the platform the script was run on (win/mac/ios/android)
script.startdate:					date script was run
script.starttime:					time script was started
script.subjectid:					assigned subject id number
script.groupid:					assigned group id number
script.sessionid:					assigned session id number
script.elapsedtime:				time it took to run script (in ms); measured from onset to offset of script
script.completed:				0 = script was not completed (prematurely aborted); 
									1 = script was completed (all conditions run)
									
parameters.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)
								
parameters.showPlayerAwins:	1 = show win status of Player A; 0 = do not show win status of player A (default)

parameters.showPlayerBwins:	1 = show win status of Player B; 0 = do not show win status of player B (default)
parameters.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 wins
totalB:							the total amount Player B wins

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EXPERIMENTAL SET-UP 
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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 

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STIMULI
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optional opponent pics -> see section Editable Stimuli

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INSTRUCTIONS 
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Instructions are not original to the task. They are provided by Millisecond Software
as htm/html pages and can be edited by changing the provided htm/html files.
To edit htm/html-files: open the respective documents in simple Text Editors such as TextEdit (Mac)
or Notepad (Windows).
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EDITABLE CODE 
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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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