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*Two-Step Decision Task ('Aliens')*
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Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com) for Millisecond Software, LLC
last updated: 10-26-2023 by K. Borchert (katjab@millisecond.com) for Millisecond Software, LLC
Script Copyright © 10-26-2023 Millisecond Software
Millisecond Software thanks Dr. Nathaniel Daw for permission to publish this script
in the Millisecond Software library!
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BACKGROUND INFO
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This script implements a batch script for the Two-step Decision task ('Alien Task') by Decker et al (2016).
The Two-step Decision task is a child-friendly task to study decision making in children using
a two-stage reinforcement learning task.
This batch script controls the assignment of 4 different payoff schedules by groupnumber assignment.
Reference:
Decker JH, Otto AR, Daw ND, Hartley CA. From Creatures of Habit to Goal-Directed Learners:
Tracking the Developmental Emergence of Model-Based Reinforcement Learning.
Psychol Sci. 2016 Jun;27(6):848-58. doi: 10.1177/0956797616639301.
Epub 2016 Apr 15. PMID: 27084852; PMCID: PMC4899156.
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TASK DESCRIPTION
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Decision Step 1:
Participants are asked to select btw two spaceships that travel to two planets with different probabilities
(e.g. spaceship1 travels to planet1 with p = 0.7 and to planet2 with p = 0.3).
Decision Step 2:
On each planet, they encounter two aliens that work in mines. Aliens retrieve treasure with 'drifting'
probabilities. Participants are asked to select one of the aliens. If the selected alien happens to retrieve
treasure from the mine, it shares it with the participant.
The goal is to collect as much treasure as possible.
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TASK DURATION
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The default duration of this task is app. 25 minutes (for 200 test trials)
