Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond
Created: January 20, 2016
Last Modified: January 01, 2023 by K. Borchert (katjab@millisecond.com), Millisecond
Script Copyright © Millisecond Software, LLC
This script implements the Weather Prediction Test , a test of probabilistic learning.
Knowlton, B.J, Squire, L.R, Gluck, M.A (1994). Probabilistic classification learning in amnesia. Learn Mem, 1, 106 –120.
25 minutes
Participants see combinations of 4 (weather) cue cards (Max number of cues presented at the same time: 3) and have to predict the weather outcome (rain vs. sunshine) based on the different cue patterns within 5s.
All cue patterns predict a weather outcome (e.g sunshine) with a predetermined probability. There are four possible cue outcome association strengths with outcome1: 75%, 58%, 43%, or 26% (approximately) with outcome 1. Feedback is given based on the actual weather outcome. Script tracks whether participants select the more probable outcome for the pattern (even if the less probable outcome was the actual outcome) across 7 blocks of 50 trials as well as for every 10 trials during the first block.
7 test blocks:
Each Block with 50 trials with pattern frequencies according to predetermined probabilities as outlined in file Probabilities.xlsx
(also see section Editable lists list.patternFrequency)
- order of pattern is randomized with the constraint that consecutive patterns are different
- actual outcomes are determined according to predetermined outcome probabilities (not frequencies) for each pattern
(see Editable lists list.p_outcome1 and list.outcomeprobabilities_pattern1 etc.)
- feedback based on actual prediction (NOT based on selecting the more probable outcome)
- participants have 5s (default) to respond. If no response is give within that time frame, the computer assumes the wrong prediction
(both actual and probable) were made.
- the cue cards get randomly allocated to be cue1 to cue4 for each participant
- by default, cue positions are randomly determined (if more than 1 card)
- an optional horizontal Prediction Bar can be presented at the top of the screen:
The bar consists of a green and a red segment.
At the beginning, both segments are of equal size. The green segment
grows with each correct prediction (while the red shrinks) and it shrinks with each
incorrect prediction (while the red on grows) throughout the task.
trial sequence:
3 cues (Max: 5000ms, response reminder after 2000ms)->Feedback based on actual prediction (2000ms) -> ITI (default: 500ms)
provided by Millisecond, see section Editable Stimuli
provided by Millisecond, see section Editable Instructions
File Name: weatherpredictiontest_summary*.iqdat
| Name | Description |
|---|---|
| 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 |
Summary Variables |
|
| propProbableChoiceOverall | Overall proportion of probable choice responses (probable choice = selecting the outcome with p > 0.5 for the given cue pattern) propProbableChoice1- |
| propProbableChoice7 | Proportion of probable choice responses in block 1-7 |
Block1: The Choices Of The First Block Are Further Analyzed By Groups Of 10 Trials |
|
| propProbableChoiceBlock11to10 | Proportion of probable choice responses in block 1, trials 1-10 |
| propProbableChoiceBlock111to20 | Proportion of probable choice responses in block 1, trials 11-20 |
| propProbableChoiceBlock121to30 | Proportion of probable choice responses in block 1, trials 21-30 |
| propProbableChoiceBlock131to40 | Proportion of probable choice responses in block 1, trials 31-40 |
| propProbableChoiceBlock141to50 | Proportion of probable choice responses in block 1, trials 41-50 |
File Name: weatherpredictiontest_raw*.iqdat
| Name | Description |
|---|---|
| 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 |
| blockCode | Name of the current block |
| blockNum | Number of the current block |
| trialCode | Name of the current trial |
| trialNum | Number of the current trial |
| cue4 | Store the itemnumber of the cues randomly assigned to be used as cue1-cue4 |
| countTestBlock | Keeps track of the number of Test Blocks run |
| pattern | Stores the current cue pattern (e.g. "1000" -> only cue1 is presented) currentCue1- |
| currentCue4 | Stores the current itemnumber of the presented cue (0 = empty) |
| pOutcome1 | Stores the probability of outcome 1 associated with the current cue pattern |
| pOutcome2 | Stores the probability of outcome 2 associated with the current cue pattern |
| outcome | Actual selected outcome 1 = outcome1 2 = outcome2 (assigned based on predetermined probabilities) |
| response | The participant's response (selected response button) |
| latency | The response latency (in ms) measured from cue onset |
| correctOutcomePrediction | 1 = correct actual outcome was predicted 0 = prediction was incorrect |
| probableOutcomePrediction | 1 = probable outcome for the pattern was predicted (=> outcome with a probability of 0.5 or above was selected) 0 = otherwise responses to pattern 6 and 9 were excluded from summary variables as probabilities for either outcome was p = 0.5 |
| propProbableChoice | Proportion of more probable outcome response per block responses to pattern 6 and 9 were excluded from summary variables as probabilities for either outcome was p = 0.5 |
The procedure can be adjusted by setting the following parameters.
| Name | Description | Default |
|---|---|---|
| outcome1 | Stores the itemnumber of outcome1 (here: 1 -> sunshine) | |
| outcome2 | Stores the itemnumber of outcome2 (here: 2 -> rain) | |
| outcome1Label | The label for outcome1 | "sunshine" |
| outcome2Label | The label for outcome2 | "rain" |
| responseWindow | The response window in ms (here: 5000ms) | |
| reminder | The reminder delay (in ms) that reminds participants to respond (here: after 2000ms) | |
| feedbackDuration | The duration (in ms) of the feedback stimuli (here: 2000ms) | |
| iti | Intertrial interval in ms | 500ms |
| randomCuePositions | True = cues appear with random horizontal positioning (default) if only 1 cue card is presented, it is always presented in the center the random positioning refers to trials that present more than 1 cue card. false = cues appear in 4 dedicated screen locations | |
| presentpredictionBar | True = presents a horizontal Prediction Bar at the top of the screen. The bar consists of a green and a red segment. At the beginning, both segments are of equal size. The green segment grows with each correct prediction (while the red shrinks) and it shrinks with each incorrect prediction (while the red one grows) throughout the task (default) false = does not present the Prediction Bar |