EstimationLine Instructions

How to use and customize the app.

The EstimationLine instructions contain information on how to access the collected data as well as configure the app. These instructions are for Version 2.

EstimationLine User Guide

The EstimationLine app is a proven estimation test for children to show where a target number should fall on a number line. In this iPad app, children touch the line with their finger to position their estimate. It is based on an experimental method originally introduced by Robert Siegler & John Opfer (2003) to examine numerical estimation. Many subsequent studies have used the method to understand the estimation capabilities of children as they develop their numerical skills. A computerized version of the number line estimation test was used in the Canadian Count Me In longitudinal study. This iPad app was tested in the field in an experiment with pre-kindergarten children in 2011.

In the EstimationLine app, the line is shown with a 0 above the left end of the line and a configurable endpoint (usually 10, 100 or 1000) above the right end, with the stimulus or target number for each trial displayed above the line. The participant (usually a child) is asked to mark the location on the number line where they think that target number belongs. In this iPad app version, the child touches the number line with their finger to mark their estimate of the target location. A red vertical mark is displayed to show their estimate. A small 'Retry' button is shown with each trial, since small children occasionally make accidental touches.

EstimationLine spares the experimenter the considerable work of converting pencil marks on paper into usable output data files. The output data for each trial is written into a trial by trial file in CSV format. The files can be retrieved via iTunes. Each trial output includes the participant's identifying information and the endpoint, the stimuli that was displayed and the participant's estimate. The estimate is computed based on the endpoint and the location they touched. The estimate is shown with up to two decimal points. For example, on a trial with a stimuli target of 9, above a line with an endpoint of 10, the touched estimate was written out to the datafile as 8.56.

The app shows configurable sets of target stimuli. Each set has many configurable aspects, such as, a single endpoint for the entire set, and the group of target or stimuli numbers that will be shown as trials in the set. After each set of trials for a particular endpoint, an option to continue to the next set is displayed for the experimenter, so that the number of sets can be adjusted for each child, based on either a predetermined design or on the child's performance. The endpoints can be modified for each set and like the stimuli, can also be pre-configured via iTunes.

The stimuli sets provided as app defaults increase in endpoint size, complexity and number of trials. These four sets of default target stimuli were created to cover the full range of development: from the pre-kindergarten children (endpoints of 10) to older grades five and six students (endpoints of 100). Each set of stimuli can be modified to meet the experimenter's needs. The app randomly shuffles the target stimuli at the start of each set to randomize the display order of the trials. The end-points of the number lines the default experiment have default values of 10, 20, 100 and 100.

There are 2 other default experiments. One allows dragging of the answer to the stimulus, instead of a direct touch on the number line. The other experiment uses a cluster of dots instead of symbolic integers as the stimulus and as the right-most endpoint.

ReferenceLinks:

Run an EstimationLine Estimation Participant

Enter Participant Information

This is the first screen displayed when the app is started. There are 3 fields for the experimenter to fill which will identify the participant's trials in the output file:

  1. ID CODE Enter the participant's ID code.
    • This code can be any mix of numbers, letters or characters (except commas). It is assumed that you have assigned the code elsewhere and that you will keep track of the code and match it with the participant name in a separate confidential file. There is no control over these ID codes in the app - if you use the same code as has been used previously, both sets of data for the same code, with the time and date of the session, will appear in the data output file.
    • The use of a code is recommended in order to separate experiment results with identifying data.
  2. GENDER Touch either the Male or Female button for the participant's gender. The selected button will be highlighted.
  3. BIRTH DATE Spin the month, day and year to view and select the participant's birthdate (the birthdate should end up in the center highlighted panel).
    • This is a useful back-up to errors entered in the participant ID code.
    • The program will compute age in months and chronological age info and this can be placed in the output .csv file to make some analysis easier using statistical analysis programs, like SPSS.

If you wish to change the experiment, then dismiss the keyboard and an experiment picker is available to make a selection.

Once you have entered and made your selection, press the "Go" button on the keyboard, or the Begin button.

Provide Participant Practice Instructions

This screen displays the default set of practice instructions. Have the participant read it or read it aloud to them. Press the Continue button once the instructions have been understood.

Coach Practice Trials

The practice opens with the number line visible on the screen with start and endpoint values. For each trial, the participant or experimenter touches the Go button (in green in the bottom control panel) to start the trial and display a green target line at a spot on the number line. At this point, any touch near the line will drop the red vertical estimate bar to show the estimate for that trial. The red Done button is then clicked to confirm the completion of the trial. The trial process then repeats until the end of the set.

A small 'Retry' button is provided in the bottom control panel after a selection. This feature was added for the experimenter following pilot testing with very young children, who occasionally accidentally touched the line, and wished to clear the estimate bar and try again. During practice, you may wish to use it to allow more tries.

At the end of a set of trials, the number line is cleared from the screen. The default question 'Continue to next set?' is displayed with End Testing and Continue buttons. Touching the Continue button launches the next set of trials. Touching the 'End Testing' button leads to the 'Done' screen, as described below.

Provide Participant Instructions

This screen displays the default set of instructions. Have the participant read it or read it aloud to them. Press the Continue button once the instructions have been understood.

Conduct Experimental Trials

The experiment opens with the number line visible on the screen with start and endpoint values. For each trial, the participant or experimenter touches the Go button (in green in the bottom control panel) to start the trial and display the target stimuli at the top of the screen. At this point, any touch near the line will drop the red vertical estimate bar to show the estimate for that trial. The red Done button is then clicked to confirm the completion of the trial. The trial process then repeats until the end of the set.

A small 'Retry' button is provided in the bottom control panel after a selection. This feature was added for the experimenter following pilot testing with very young children, who occasionally accidentally touched the line, and wished to clear the estimate bar and try again.

At the end of a set of trials, the number line is cleared from the screen. The default question 'Continue to next set?' is displayed with End Testing and Continue buttons. Touching the Continue button launches the next set of trials. Touching the 'End Testing' button leads to the 'Done' screen, as described below.

Done Screen - Start Next Participant

Once the End Testing button has been selected to avoid continuing to further sets, or all sets have been completed, the number line and control panel are removed and the word 'Done' is displayed. At this point, the iPad should be retrieved from the participant.

At this point, you can start a new participant via the button at the bottom of the screen or use another app by clicking the Home button on the iPad. Don't worry about 'closing' the EstimationLine app. Apps are normally left running - the concept of 'opening' and 'closing' is not applicable to apps.

EstimationLine Method: Trial Sequences

The EstimationLine app was field-tested in a study of young children in daycare settings conducted by Jo-Anne LeFevre of Carleton University in October-November 2011. Experimenters in the study reported that the children enjoyed using the iPad and had no trouble touching the line. Some children in the study were already familiar with the iPad from home use. As expected, many of the young children performed only a single set, and even those trials often did not appear to reflect much knowledge of the number line.

Default Stimuli Sequences

Here are the default stimuli files. Each set is 'shuffled' before it is displayed, so that the targets appear in a random order for each participant.

The stimuli sets are designed to provide balanced coverage of the number line and progress in difficulty to accommodate testing with very young children. However, your stimuli design will depend on the age-groups you are studying and the goals of the study. See below for instructions on how to customize stimuli files to set up different target stimuli for the sets.

defaultstimulusset1.txt
trialID:100,trialStimulus:%10
trialID:101,trialStimulus:%20
trialID:102,trialStimulus:%30
trialID:103,trialStimulus:%40
trialID:104,trialStimulus:%50
trialID:105,trialStimulus:%60
trialID:106,trialStimulus:%70
trialID:107,trialStimulus:%80
trialID:108,trialStimulus:%90
  • The settings that are specific to each trial must all be on one line since the lines are usually all shuffled. Each setting is a setting key and a colon with the setting value after the first colon. The settings are each separated by a comma.
  • The first setting trialID:101 is really a user defined marker that will be placed in the trial output. It can be used to trace the trial back to other test conditions. It is recommended to keep many unique values in case your data gets merged. The value, here 101, is a string that will be placed into the .csv output. You can use any text, although numbers may work better for your statistical analysis program.
  • The second setting trialStimulus:%20 is the actual trial stimulus question. This one is formatted as a percentage - the app adjusts them according to the endpoints provided for that set before they are displayed.
    • For example: trialStimulus:%20 would be displayed as 2 for an endpoint of 10, 4 for an endpoint of 20, or 200 for an endpoint of 1000.

The rest of the default stimulus sets for the touch experiment are:

defaultstimulusset2.txt
trialID:200,trialStimulus:%5
trialID:201,trialStimulus:%10
trialID:202,trialStimulus:%15
trialID:203,trialStimulus:%20
trialID:204,trialStimulus:%25
trialID:205,trialStimulus:%30
trialID:206,trialStimulus:%35
trialID:207,trialStimulus:%40
trialID:208,trialStimulus:%45
trialID:209,trialStimulus:%50
trialID:210,trialStimulus:%55
trialID:211,trialStimulus:%60
trialID:212,trialStimulus:%65
trialID:213,trialStimulus:%70
trialID:214,trialStimulus:%80
trialID:215,trialStimulus:%85
trialID:216,trialStimulus:%90
trialID:217,trialStimulus:%95
defaultstimulusset3.txt
trialID:300,trialStimulus:%5
trialID:301,trialStimulus:%11
trialID:302,trialStimulus:%18
trialID:303,trialStimulus:%25
trialID:304,trialStimulus:%33
trialID:305,trialStimulus:%40
trialID:306,trialStimulus:%46
trialID:307,trialStimulus:%52
trialID:308,trialStimulus:%58
trialID:309,trialStimulus:%65
trialID:310,trialStimulus:%71
trialID:311,trialStimulus:%78
trialID:312,trialStimulus:%85
trialID:313,trialStimulus:%93
trialID:314,trialStimulus:%99
defaultstimulusset4.txt
trialID:400,trialStimulus:%2
trialID:401,trialStimulus:%8
trialID:402,trialStimulus:%15
trialID:403,trialStimulus:%22
trialID:404,trialStimulus:%30
trialID:405,trialStimulus:%37
trialID:406,trialStimulus:%43
trialID:407,trialStimulus:%49
trialID:408,trialStimulus:%55
trialID:409,trialStimulus:%62
trialID:410,trialStimulus:%68
trialID:411,trialStimulus:%75
trialID:412,trialStimulus:%82
trialID:413,trialStimulus:%90
trialID:414,trialStimulus:%96

Experiment Configuration

Now we will examine the default touch experiment configuration file. We will build up the whole configuration picture.

defaultexperiment.txt
trialbase:defaultpracticeconfig.txt
trialsetid:default
outputspec:defaultoutputspec.txt
outputfile:practicetrials
stimulusfile:defaultstimuluspractice.txt
trialbase:defaultnumberlineconfig.txt
outputfile:numberlinetrials
stimulusfile:defaultstimulusset1.txt
trialEndValue:20
trialEndMarker:20
instructions:none
stimulusfile:defaultstimulusset2.txt
trialEndValue:100
trialEndMarker:100
stimulusfile:defaultstimulusset3.txt
stimulusfile:defaultstimulusset4.txt

First notice the previous 4 stimulus files are called up using the setting stimulusfile:defaultstimulusset1.txt. The configuration lines in this file are all processed until they hit the stimulusfile setting. The stimulus set is shuffled and presented to the subject. When the set is finished then more of the experiment file is processed up to the next stimulusfile setting. The settings will overwrite any previous values. In this experiment file between set1 and set2 the numberline endpoint is changed from app default of 10 to 20 using the settings trialEndValue:20 trialEndMarker:20. This pair of settings tells the app the real value of the end of the numberline and supplies the text to show above the end of the number line.

The setting instructions:none means do not show any instructions before the following stimulus set. To understand why this setting is here we need to investigate the setting helper setting trialbase:defaultnumberlineconfig.txt. The trialbase indicates a file that also contains settings. This is a helper allowing reuse between many experiments or when alternating between different types of trial sets. Let's look at this file

defaultnumberlineconfig.txt
instructions:defaultinstructions.txt
trialType:integer
trialEndValue:10
trialEndMarker:10

Here is where the instructions file setting was hiding as well as the original endpoint of 10.

The setting trialsetid:default is simply a string that can be configured to show in the outpufile and can further aid to remind you about the testing scenario used.

Output Configuration

Now we will examine the settings that control the experiment output.

The setting outputfile:numberlinetrials is a way to specify the file name of the output; it will be numberlinetrials.csv. in the default experiment above there is also the setting outputfile:practicetrials. This causes the results of practice trails to go to a different file that can be processed to look for touch error amounts or thrown away.

Now we will examine the output configuration file specified by the setting outputspec:defaultoutputspec.txt.

defaultoutputspec.txt
participantid:id
participantgender:gender
participantbirthdate:birthdate
participantagechronological:chronologicalage
participantageinmonths:ageinmonths
trialID:trialid
trialdate
trialmsfirsttouch
trialStimulus
selected

This file contains one line specifying each column of the output.csv. This allows you to only deal with items of interest in your experiment. The first word is the app internal setting key as documented in various tables in this documentation. It is optionally followed by a colon and a string that you wish to be the name used as the output table header. In the default, you can see participantagechronological:chronologicalage allows the longer internal key to be shortened.

Here is sample output produced from the first default stimulus set.

numberlinetrials.csv

id

gender

birthdate

chronologicalage

ageinmonths

trialid

trialdate

trialmsfirsttouch

trialStimulus

selected

byj22 m 2008-04-26 6-0-0 72 101 2014-04-26 19:05:42 3503 %20 1.91
byj22 m 2008-04-26 6-0-0 72 106 2014-04-26 19:05:48 1835 %70 6.37
byj22 m 2008-04-26 6-0-0 72 103 2014-04-26 19:05:53 1903 %40 3.49
byj22 m 2008-04-26 6-0-0 72 105 2014-04-26 19:05:57 2451 %60 5.62
byj22 m 2008-04-26 6-0-0 72 107 2014-04-26 19:06:01 1965 %80 7.78
byj22 m 2008-04-26 6-0-0 72 102 2014-04-26 19:06:06 1798 %30 2.60
byj22 m 2008-04-26 6-0-0 72 100 2014-04-26 19:06:10 1516 %10 1.19
byj22 m 2008-04-26 6-0-0 72 108 2014-04-26 19:06:14 2123 %90 8.76
byj22 m 2008-04-26 6-0-0 72 104 2014-04-26 19:06:18 1742 %50 5.06

Retrieving Collected Data

To access the data file:
  1. Open iTunes on your computer.
  2. Connect the EstimationLine iPad to the computer.
  3. Select the iPad in the "Devices" list.
  4. Go to the "Apps" tab using the tab bar at the top.
  5. Scroll down to the "File Sharing" section.
  6. Select the EstimationLine app from the list.
  7. Select the numberlinetrials.csv file in the file list.
  8. Now:
    • To download the data file from the iPad:
      Press the "Save to..." button and select a location to save the file.
    • To clear existing data and start a new data file:
      With the data file selected, press the delete key on your keyboard.
      Press the delete button in the dialog that appears.

The File Sharing screen in iTunes

Screenshot of iTunes.

Data File Format

The session data is stored the file named numberlinetrials.csv or whatever was specified as the outputfile setting. EstimationLine uses CSV format, with column headers on the first line, to allow for easy interoperation with programs like Excel and SPSS. Each row in the output file stores the data for one trial.

The outputspec setting declares a file that can use these settings that relate to the experiment participant.

outputspec Key

Description

participantid

This contains the string entered on the Participant Info Screen in the Participant ID field.

participantgender

This contains the string value of the Gender selector from the Participant Info Screen. m for male. f for female.

participantbirthdate

This contains a string representing the birth date selected on the Participant Info Screen. The format is yyyy-MM-dd

participantbirthdateunknown

If it was indicated on the Participant Info Screen that the birth date was not known then this value will be 1 otherwise it will be 0

participantagechronological

This is a string representing the participant’s age on the day of the test. It uses the entered birth date as the start and the output is in a format of 3 separated numbers years-months-days for example 5-6-10 for a child 5 years 6 months and 10 days old. This saves work in the statistical analysis, as it is a common step to break down the age this way.

participantageinmonths

This is the participants age in months and is computed from the participantagechronological. The formula is 12 * years + months + (1 if days > 15). This form of rounding matches the calculation used in norms for other testing tools.

The outputspec setting declares a file that can use these settings that relate to the trial results.

outputspec Key

Description

trialdate

This is the date and time when the “Go” button is pressed to start the trial presentation. It is a string with the format yyyy-MM-dd HH:mm:ss ( reference http://www.unicode.org/reports/tr35/tr35-31/tr35-dates.html#Date_Format_Patterns )

trialselecteddate This is the date and time when the first touch is registered near the number line. For a touch based trial this will be the time of the answer event. For a dragging based trial this is the time when the first drag started.
trialendselecteddate This is the date and time when the last touch is ended near the number line. For a touch based trial this will be after the time of the answer event since it will take time to lift the finger from the iPad touch screen. For a dragging based trial this is the time when the last drag ended.
trialdoneselecteddate This is the date and time when the “Done” button is pressed to end the trial. It may not be a very useful time as many participants may sometimes delay before pressing “Done”. It is here for completeness.
selected This is the selected answer value from the number line printed to 2 decimal places.
retrycount This is the number of times that the retry button was used in the trial.
dragcount This is a number of the count of individual drags used in the trial or retrial id Retry button pressed.
lastretrystartdate This is the date and time when the “Retry” button was last pressed to restart the trial.
trialmsfirsttouch

This is the integer time in milliseconds of trialselecteddate from the time of the original “Go” button or the last “Retry” button and represents the time from the Go button hit to the answer touch for touch trials. Essentially the last retry time; consult retrycount to see if retries were used.

trialmsendtouch

This is the integer time in milliseconds of trialendselecteddate from the time of the original “Go” button or the last “Retry” button and represents the time from the Go button hit to the end of dragging or end of touching.

trialmsdone

This is the integer time in milliseconds of trialdoneselecteddate from the time of the original “Go” button and represents the time from the Go button hit to the Done button.

trialmsdonelasttry

This is the integer time in milliseconds of trialdoneselecteddate from the time of the original “Go” button or the last “Retry” button and represents the time from the Go button hit to the Done button.

It depends on the experiment to decide which of these results will be of interest. You can collect them all and decide later, but it makes the files more difficult to scan due to the many dates.

Customization Options for the EstimationLine App

EstimationLine uses .txt-format files for custom configuration. It is recommended that you use UTF-8 encoded text files with UNIX (LF) line endings.

Steps to setup custom configuration files

  • Prepare a set of configuration test files, preferably keeping them in a folder with a date an version number that you can locate later if needed.
  • For big changes, make a copy of your configuration folder and modify the files, saving the folder with a new date and version number.
  • Place the configuration files on the iPad with the ones you have modified. Use the steps in "Getting Configuration Files On the iPad"
  • Test your experiment and make adjustments to the files in your folder as needed. Reload the changed ones to the iPad.

Getting Configuration Files On the iPad

  1. Open iTunes.
  2. Connect the EstimationLine iPad.
  3. Select the iPad in the "Devices" list.
  4. Go to the "Apps" tab using the tab bar at the top.
  5. Scroll down to the "File Sharing" section.
  6. Select the EstimationLine app from the list.
  7. Now:
    • To replace a default configuration file with one from your computer:
      1. Press the "Add..." button.
      2. Select the configuration file on your computer that you want to put on the iPad.
      3. Click "Replace" in the dialog that appears
    • To replace a modified configuration file on the iPad with the default:
      1. With the configuration.txt file selected, press the delete key on your keyboard.
      2. Press the delete button in the dialog that appears.
    • This is always a good time to archive any .csv files that contain the experimental results. Save them in a named and dated folder as well.

Main Config File Format

The configuration.txt file is a list of keys and values separated by colons. In the following format:


setting1:value1
setting2:value2
				

The most basic start of a custom configuration is a file like this

configuration.txt
experimentList:experimentlist.txt

A basic list of experiment files is supplied that will be displayed in the experiment selector under the keyboard on the Participant Info Screen.

experimentlist.txt
Default Number Line Experiment:defaultexperiment.txt
Dragging Number Line Experiment:experimentdrag.txt
Touching Number Line Experiment:experimenttouch.txt

The names displayed in the Experiment Picker are to the left of the colon and the name of the experiment text file to use for the chosen experiment follows.

There may be other reasons to add to the configuration.txt file. The labels and button text are configurable. This allows for customization of an experiment in an alternate language, or with terms more appropriate to the type of experiment. Following is a table of the settings that relate to the experiment interface elements.

Setting Key

Default Value

Screen

Description

participantTitle Enter Participant Info Identification Title of Participant basic data entry screen
participantLabel Participant ID Identification Form field label for entering the coded participant Identification code
genderLabel Gender Identification Form Field label for the gender selector
maleTitle Male Identification Male gender label for selector
femaleTitle Female Identification Female gender label for selector
birthDateLabel Birth Date Selector Identification Initial Label for the birth date picker
birthdateSetLabel Birth Date Identification Birth date picker label changes to this label when a date is chosen with the picker wheels
birthdateNotKnownLabel Birth Date Not Known Identification The picker label changes to this after the Birth date not known button is selected
birthdateIntentTitle I don’t know the Birth Date Identification Button Label to chose when the birth date of the participant is not known
birthdateIntentSetTitle Set the Birth Date Identification Button Label used to reshow the birth date picker
beginButtonTitle Begin Identification The button label used to move to the first step of the subject trials.
instructionContinueTitle Continue Instructions This is the label of the button to continue to the first trial of a set.
instructionBackTitle <Back Instructions Back Button label to return to Identification screen.
playButtonTitle Go Number Line Label of button to start a trial.
endButtonTitle End Number Line Label of button to skip to Inter-set screen
retryButtonTitle Retry Number Line Label of Button to allow another trial guess for current trial.
selectText Touch where the number should go. Number Line Lower bar prompt after the “Go” button is pressed.
okText Is this good? Number Line Lower bar prompt after the trial result is guessed.
playText Press the “Go” button to see the number. Number Line Lower bar prompt before trial is started.
whereIsText Where Is Number Line The stimulus prompt question.
nextTrialQuestion Continue to next set? Inter-set screen This question is presented after a stimulus set is complete.
endTestingTitle End Testing Inter-set screen Button label to end this test for this participant.
continueTitle Continue Inter-set screen Button label to continue to the next stimulus set.
doneButtonTitle Done End of Test The status text showing that the test sets are all complete.
doneContinueTitle New Participant End of Test Text for button that returns to the first Identification page for a new participant.

The setting values that configure the experiment behaviour are listed in the following table

Setting Key

Default Value

Description

instructions none

none means there are no instructions presented before a stimulus trial set. Typically this should be set to a filename in the documents directory such as: instructions:practiceinstructions.txt before the practice trial set. Set to instructions:instructions.txt before the first real trial set; and then set to instructions:none for any subsequent sets with the same instructions so it will not present between all trial sets.

You must also create these files with the appropriate instruction wording and place them in your documents directory.

allowConfiguration 1

For future use. If set to allowConfiguration:0, then access to the configuration will be disallowed on the iPad to keep it from being modified in the field. It has a default of allowConfiguration:1 but is not operational in this version.

hasTarget 0

If set to hasTarget:1 then a green “Answer” marker will appear at the correct place on the number line. This is used to set up practice touching or dragging trials. The marker is shown but the stimulus is not shown.

showStimulus 1

Set this value to showStimulus:0 for the practice trials so that the stimulus is not shown that matches the target marker. This keeps the subject from gaining any knowledge during the practice trials.

trialType integer

trialType:integer is the basic type of trial type that will present a symbolic integer to be located on the number line.

trialType:cluster is used to present a cluster of dots as the trial stimulus.

shuffleTrials 1

Setting this to shuffleTrials:0 will present all the trials in the order that they are in the stimulus file. This will allow a consistent trial presentation order if desired. The normal shuffleTrials:1 will randomly shuffle the trial stimulus set using a Fisher-Yates shuffle.

trialStartValue 0 This is the value of the left-most end of the number line; for now an integer value. Leave this value at zero for now as full support is not implemented.
trialStartType integer Future use.
trialStartMarker 0 Future use.
trialEndValue 10

This is the value of the right-most end of the number line; for now an integer value. This must be set to make an experiment with a different end value; for example trialEndValue:100 to present a number line with endpoints 0 and 100. This field is the true numerical value that the program needs to do calculations.

trialEndType integer

trialEndType:integer displays the right-most end of the number line as a symbolic integer.

trialEndType:cluster displays the right-most end of the number line as a non-symbolic cluster of trialEndValue red dots.

trialEndMarker 10

This is the text value of the right-most end of the number line; for now an string value. This must be set to make an experiment with a different end value; for example trialEndValue:100 to present a number line with endpoints 0 and 100. It is possible to set this to trialEndValue:ten

requireBirthDate 0

Setting to requireBirthDate:1 will not allow the testing to proceed without a birthdate being entered.

dragsAllowed 0

The default dragsAllowed:0 means that a touch must be used to indicate the position on the number line. Setting this to dragsAllowed:3 will enable dragging of the answer marker to the answer point on the number line. It will allow 3 drags to a final position as well.

retriesAllowed 5 This is the number of times that a retry is allowed for a trial. These are abnormal events that are used in case the subject accidently touched where they did not intend to touch. The experimenter enables a retry.
selectorStart none

The default selectorStart:none means that the selector does not show when the stimulus is presented. This is the common value for a touch trial.

The setting selectorStart:0 means that the selector is shown when the stimulus is presented, in this case at the value 0 on the number line. This is the common value for a dragging trial.

experimentList defaultexperimentlist.txt

This is the main setting to allow a custom trial configuration. In the default setting, only the built-in experiments will show up in the experiment picker under the keyboard on the participant identification screen.

To setup experiments of your own then you must add a file to the documents directory called configuration.txt

In this master configuration file you include this setting, such as:

experimentList:experimentlist.txt

This instructs the program to use the contents of a file experimentlist.txt to get a list of available experiments.

In the experiment file there is a special setting trialbase. After it is rhe name of a file that can store some of the settings in the previous 2 tables. These can be switched with a different trialbase as needed. This allows a group of compatible settings to be reused in different experiment definitions.

Contact us at apasoehps@hume.ca if you still have questions that weren't answered by this page. We can also consult on building custom experiment files to meet your needs.

© Steve Hume 2014.