Time Wall Estimation Task

Technical Manual

Script Author: Katja Borchert, Ph.D. (katjab@millisecond.com), Millisecond

Created: January 07, 2015

Last Modified: January 09, 2026 by K. Borchert (katjab@millisecond.com), Millisecond

Script Copyright © Millisecond Software, LLC

Background

This script implements a Time Wall Task; an assessment of time estimation. The implemented procedure is based on Englund et al (1987).

References

UNIFIED TRI-SERVICE COGNITIVE PERFORMANCE ASSESSMENT BATTERY (UTC-PAB) I. DESIGN AND SPECIFICATION OF THE BATTERY. ENGLUND, C.E., REEVES. D.L., SHINGLEDECKER, C.A., THORNE, D.R., WILSON, K.P., & HEGGE. F.W. (1987). REPORT NO. 87-10, NAVAL HEALTH RESEARCH CENTER, P 0 BOX 85122, SAN DIEGO, CALIFORNIA 92138 NAVAL MEDICAL RESEARCH AND DEVELOPMENT COMMAND, BETHESDA, MARYLAND (p.46)

Duration

1.5 minutes

Description

Participants watch a disk falling from the top of the screen. On its way to the bottom (default: 10s) it passes behind a wall with a disk-sized hole in it. Once the disk is completely behind the wall (default: 6s), participants are asked to estimate via pressing the Spacebar how long it would take the disk to completely cover the hole (default: 8s, measured from start of trial).

Procedure

By default this script runs 10 estimation tasks (editable parameter) or is over after 300s (editable parameter)
whichever comes first. At the default speed the disk is completely covered by the wall by 6s, covers the wall hole
by 8s and drops off the canvas at 10s.

Once the disk is completely covered by the wall, the script waits for a response from the participant
(early responses are counted but ignored otherwise).

If participant presses the Spacebar within 30s (editable parameter) after the disk is completely covered by the wall,
the response is counted as valid and the wall hole is filled with the color of the falling disk
(visual feedback of a valid response).

A new estimation task (if applicable) is started after 500ms (editable parameter).
If participant does not press the Spacebar within 30s, a beep is played (auditory feedback of invalid response)
and a new task starts after 1s (editable parameter).

SCREEN SET-UP
The stimuli in this task are all proportionally sized to the active screen canvas
(this script uses a width:height = 4:3 canvas by default)

Instructions

adapted from Englund et al (1987) - can be edited
in script timewallestimation_instructions_inc.iqjs

Summary Data

File Name: timewallestimation_summary*.iqdat

Data Fields

NameDescription
inquisit.version Inquisit version number
computer.platform Device platform: win | mac |ios | android
computer.touch 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities
computer.hasKeyboard 0 = no external keyboard detected; 1 = external keyboard detected
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
countResponses Counts all valid responses
nrTimeouts Counts number of time-outs (= number of invalid responses)
timeHole The time (in ms) it should take trial.diskfalling theoretically to move the disk the distance from first time behind the wall
to cover the wall hole completely.
meanEstimationTime Mean estimation time of judging how long it takes the disk to fill the wall hole
(measured from time that disk is completely covered by wall)
constantError Estimation error as measured by difference (mean_estimationtime - time_hole)
propError Proportional error of estimated time to actual time
variableError Standard deviation time of judging how long it takes the disk to fill the wall hole
(measured from time that disk is completely covered by wall)
inaccuracyScore The percentage difference between the mean estimation Time and the actual timeHole Time
cvEstimationTime Coefficient of variation (Englund et al: 100* std/mean), measure of response Consistency across trials
sumEarlyResponses Sums up the number of early responses across experiment
circleradius Sets the radius of the disk in canvas height % (default: 5%)
totalfallduration Sets the time (in ms) needed for the disk to fall from the top (not seen yet) to the bottom (not seen anymore) (default: 10000ms)
nrStepsDestinationWall Sets the canvas % steps the disk needs to be fully covered by wall (default: 66)
nrStepsDestinationHole Sets the canvas % steps the disk needs to fully cover the wall hole (default: 88)
speed Calculates the speed in ms/% canvas of the falling disk based on totalfallduration and the start and end y-coordinates of the falling disk
timeHole Calculates the time (in ms) it takes for disk to fully cover the hole
timeWall Calculates the time (in ms) it takes for disk to be fully covered by wall
startY Calculates the starting y coordinate of the falling disk based on circleradius (start: disk is not yet seen)
endY Calculates the ending y coordinate of the falling disk based on circleradius (end: disk is not seen anymore)
walltopY Calculates the y-coordinate of the top of the wall based on (parameter) circleradius and (parameter) nrStepsDestinationWall
wallY Calculates the y-coordinate of the wall when it first covers the disk completey based on (parameter) circleradius and (parameter) nrStepsDestinationWall
holeY Calculates the y-coordinate of the hole based on (parameter) circleradius and (parameter) nrStepsDestinationHole

Raw Data

File Name: timewallestimation_raw.iqdat

Data Fields

NameDescription
build Inquisit version number
computer.platform Device platform: win | mac |ios | android
computer.touch 0 = device has no touchscreen capabilities; 1 = device has touchscreen capabilities
computer.hasKeyboard 0 = no external keyboard detected; 1 = external keyboard detected
date Date the session was run
time Time the session was run
subject Participant ID
group Group number
session Session number
blockcode The name the current block (built-in Inquisit variable)
blocknum The number of the current block (built-in Inquisit variable)
trialcode The name of the currently recorded trial (built-in Inquisit variable)
trialnum The number of the currently recorded trial (built-in Inquisit variable)
trialnum is a built-in Inquisit variable; it counts all trials run
even those that do not store data to the data file.
totalfallduration The time (in ms) it takes for the disk to fall from the top (starting off canvas) to the bottom (ending off canvas)
response The participant's response (57 = pressed Spacebar within valid response window)
validResponse 1 = a valid response within the response window was given
0 = no valid response within the response window was given
timeHole The time (in ms) it takes for disk to fully cover the hole (from start of falling) => "correct" response
estimatedTime Stores the estimated time (in ms) disk would fully cover the wall hole
(measured from trial start until participant responds)
earlyResponses Sums up the early responses (=> pressing Spacebar before disk is fully behind wall) per trial
early responses don't interrupt the trial

Parameters

The procedure can be adjusted by setting the following parameters.

NameDescriptionDefault
Design
nrStepsDestinationwall Sets the steps (1 step = 1% of the canvas height) the disk needs to take from the start point to the point where it's first fully covered by wall66
nrStepsDestinationhole Sets the steps (1 step = 1% of the canvas height) the disk needs to fall from the start point to the point where it fully covers the wall hole88
nrEstimations Number of estimation cycles10
Sizing Parameters
circleRadius Sets the radius of the disk in canvas height %
sets the steps (1 step = 1% of the canvas height) the disk needs to fall from the start point to the point where it fully covers the wall hole
5%
Timing Parameters
totalfallDuration Sets the time (in ms) needed for the disk to fall from the top (not seen yet) to the bottom (not seen anymore)10000
maxTime The total time (in ms) the test should maximally take
the script stops either after parameters.nr_estimations (10) or parameters.maxtime; whichever comes first
300000
maxTrialDuration Maximum trial duration for trial.fallingdisk30000
beepPause Time-out pause after a beep trial (= participant took longer than parameters.max_trialduration to respond) before the next estimation sequence is started1000
iti The intertrial pause (in ms) after each valid time estimation cycle500
Response Keys
responseKey The response key (" " -> spacebar)" "