Game of Dice Task

Technical Manual

Script Author: David Nitz (dave@millisecond.com) for Millisecond Software LLC for Millisecond Software, LLC

Last Modified: March 25, 2025 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC

Script Copyright © Millisecond Software, LLC

Background

This script implements the 'Game of Dice Task' (GDT), a test of risky gambling decisions, with and without feedback (optional).

The implemented procedure is based on:

(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.

Duration

5 minutes

Description

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.

Procedure

• 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.
Instructions can be edited in gameofdicetask_instructions.inc.iqjs

Summary Data

File Name: gameofdicetask_summary*.iqdat

Data Fields

NameDescription
inquisit.version Inquisit version number
computer.platform Device platform: win | mac |ios | android
startDate Date the session was run
startTime Time the session was run
subjectId Participant ID
groupId Group number
sessionId Session number
elapsedTime Session duration in ms
completed 0 = Test was not completed
1 = Test was completed
gdtVersion 1 = original version with feedback (default)
2 = version without feedback
accountBalance 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)
netScore 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

Raw Data

File Name: gameofdicetask_raw*.iqdat

Data Fields

NameDescription
build Inquisit version number
computer.platform Device platform: win | mac |ios | android
date Date the session was run
time Time the session was run
subject Participant ID
group Group number
session Session number
gdtVersion 1 = original version with feedback (default)
2 = version without feedback
blockCode Name of the current block
blockNum Number of the current block
currentRound Stores the current round number
trialCode Name of the current trial
trialNum Number of the current trial
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)
accountBalance 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)
netScore 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

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
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")