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										Game of Dice Task (GDT)
SCRIPT INFO

Script Author: David Nitz (dave@millisecond.com) for Millisecond Software LLC for Millisecond Software, LLC
last updated: Katja Borchert (katjab@millisecond.com) for Millisecond Software LLC for Millisecond Software LLC

Script Copyright © 08-29-2017 Millisecond Software


BACKGROUND INFO 

											*Purpose*
	This script implements the 'Game of Dice Task' (GDT) with and without feedback as described in:
	
	(with feedback):
	Brand, M., Fujiwara, E., Borsutzky, S., Kalbe, E., Kessler, J., & Markowitsch, H.J. (2005). 
	Decision-making deficits of Korsakoff patients in a new gambling task with explicit rules -
	associations with executive functions. Neuropsychology, 19, 267–277.

	and
	
	(without feedback)
	Brand, M. (2008). Does the feedback from previous trials influence current decisions? A study on the role 
	of feedback processing in making decisions under explicit risk conditions. 
	Journal of Neuropsychology, 2, 431-443.

	
	By default the script plays the version WITH feedback. To play the version WITHOUT feedback, go to
	Editable Task Parameters -> parameters.GDTversion and change to parameters.GDTversion = 2.


											  *Task*
A dice is being rolled and participants have to bet on the outcome.
They have the choice between 4 different kinds of bets:
- a single bet (betting on a specific dice face: earns the most money if correct, but loses the most if incorrect (very risky bet)
- a dual bet (betting on two possible dice faces: if either one of them is rolled, it's a win. earns/loses slightly less than single bet (risky bet)
- a triple bet (betting on three possible dice faces: earns/loses less than dual bet (safe bet)
- a quadruple bet (betting on four possible dice faces: ears/loses the least (safest bet)
Participants can quit at any point before the default rounds (18) are played.


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

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

build:							Inquisit build
date, time, subject, group:		date and time script was run with the current subject/groupnumber 
/GDTversion:					1 = original version with feedback (default); 2 = version without feedback
blockcode, blocknum:			the name and number of the current block
/currentround:					stores the current round number
trialcode, trialnum: 			the name and number of the currently recorded trial
								(Note: not all trials that are run might record data) 
latency: 						the response latency (in ms)
/chosen:						the selected dice faces participants is betting on (example: "1", "12", "123", "1234")
/throw:							the dice face thrown
/row:							reflects participant's betting choice: 
								For "singles" ("1", "2", etc.) values.row = 1
								For "doubles" ("12", "34", etc.) values.row = 2 
								For "triples" ("123", "456") values.row =3
								For "quadruples" ("1234", etc.) values.row = 4
/currentbet:					the amount of money currently bet on values.chosen
/gain:							amount of money won or lost in the current round (e.g. -500)
/account_balance:				Amount participant owns
/single:						counts how many times participant has bet on 1 specific dice face
/double:						counts how many times participant has bet on 2 possible dice faces
/triple:						counts how many times participant has bet on 3 possible dice faces
/quadruple:						counts how many times participant has bet on 4 possible dice faces
/safe:							counts how many times participants selected a safe bet (bets on 3 or 4 dice faces)
/risky:							counts how many times participants selected a risky bet (bets on 1 or 2 dice faces)
/net_score:						reflects the number of safe (bets on 3 or 4 numbers) vs. risky (bets 
								on 1 or 2 numbers) choices. It is computed as number of safe bets minus number of risky bets.
/wins:							adds the number of winning bets
/losses:						adds the number of losing bets


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

script.subjectid:				subject id number
script.startdate:				date script was run
script.starttime:				time script was started
script.elapsedtime:				time it took to run script (in ms)
/completed:						0 = script was not completed; 1 = script was completed (all conditions run)
/GDTversion:					1 = original version with feedback (default); 2 = version without feedback
/account_balance:				amount participant owns at the end
/single:						counts how many times participant has bet on 1 specific dice face
/double:						counts how many times participant has bet on 2 possible dice faces
/triple:						counts how many times participant has bet on 3 possible dice faces
/quadruple:						counts how many times participant has bet on 4 possible dice faces
/safe:							counts how many times participants selected a safe bet (bets on 3 or 4 dice faces)
/risky:							counts how many times participants selected a risky bet (bets on 1 or 2 dice faces)
/net_score:						reflects the number of safe (bets on 3 or 4 numbers) vs. risky (bets 
								on 1 or 2 numbers) choices. It is computed as number of safe bets minus number of risky bets.
/wins:							adds the number of winning bets
/losses:						adds the number of losing bets


* separate data files: to change to one data file for all participants (on Inquisit Lab only), go to section
"DATA" and follow further instructions


EXPERIMENTAL SET-UP

* by default max. 18 rounds get played (set under section Editable Parameters)
* participant can quit at any point
* the faces are selected randomly without replacement from list.rolldice
* by default, participant get feedback of the dice throw and updating of account information


STIMULI
Revised instructions, visuals and other procedural details thanks to the helpful and generous input from the original authors.

INSTRUCTIONS
Revised instructions, visuals and other procedural details thanks to the helpful and generous input from the original authors.

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:

	GDTversion:				1 = original version with feedback (default); 
							2 = version without feedback
								Note: adjust instructions accordingly under section Editable Instructions
	nrounds_gdt: 			Number of rounds in feedback version (must be a multiple of 6); default is 18
	nrounds_gdt_nf: 		Number of rounds in no-feedback version (must be a multiple of 6); default is 18
								IMPORTANT: When in- or decreasing the number of rounds in either version, adjust 
								the number of items in list.rolldice accordingly.
	account_balanceStart: 	Amount of points / Money at Task Onset
	currency: 				Exchange "$" with "€", "£", "¥", etc.
	gainsingle: 			Amount to be won/lost when betting on a single number (e.g. "3")
	gaindouble: 			Amount to be won/lost when betting on a combination of two numbers (e.g. "5 or 6")
	gaintriple: 			Amount to be won/lost when betting on a combination of three numbers (e.g. "1 or 2 or 3")
	gainquadruple:			Amount to be won/lost when betting on a combination of four numbers (e.g. "2 or 3 or 4 or 5")

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