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Data Structures with shared data
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Explore/Exploit Task

0 Shared Subjects

A 2-armed bandit task in which each block initially samples from 2 stimuli with fixed reward probabilities, then introduces additional stimuli later in the block. A stimulus can be reused in future blocks with new reward probabilities, dissociating stimulus novelty from stimulus value uncertainty. [https://doi.org/10.1016/j.neuropsychologia.2011.04.026]
Clinical Assessments
Task Based
View Change History
Query Element Name Data Type Size Required Description Value Range Notes Aliases
subjectkey GUID Required The NDAR Global Unique Identifier (GUID) for research subject NDAR*
src_subject_id String 20 Required Subject ID how it's defined in lab/project
interview_date Date Required Date on which the interview/genetic test/sampling/imaging/biospecimen was completed. MM/DD/YYYY
interview_age Integer Required Age in months at the time of the interview/test/sampling/imaging. 0 :: 1260 Age is rounded to chronological month. If the research participant is 15-days-old at time of interview, the appropriate value would be 0 months. If the participant is 16-days-old, the value would be 1 month.
sex String 20 Required Sex of subject at birth M;F; O; NR M = Male; F = Female; O=Other; NR = Not reported
experiment_id Integer Recommended ID for the Experiment/settings/run
sessionid1 Integer Recommended ID for session For in-lab subjects, sessionID corresponds to the visit number. For online subjects, sessionID = 1 sessionid
blockid Integer Recommended Current block number 0 = OldNew task portion; blockID begins with 1 for the main task
trialid1 Float Recommended Number of trial within current block Begins with 1 trialid
trialstimid_1 Float Recommended ID of left stimulus in the set of all stimuli shown during the task
trialstimid_2 Float Recommended ID of right stimulus in the set of all stimuli shown during the task
trialstimreward_1 Integer Recommended If chosen, did the left stimulus result in a win? 0;1 0 = No; 1 = Yes
trialstimreward_2 Integer Recommended If chosen, did the right stimulus result in a win? 0;1 0 = No; 1 = Yes
rt_01 Float Recommended Time elapsed between stimulus onset and subject reponse In milliseconds. -999 indicates missed response (subject took longer than 2s) rt
respkey Integer Recommended Explore-Exploit Task - Subject response key 1;2;-999 During main task: 1 = Left; 2 = Right; -999 = Miss (subject took longer than 2s to respond). During Old/New task: 1 = Old; 2 = New.
selectedstimid Integer Recommended ID of selected stimulus in the set of all stimuli shown during the task
outcome_02 Integer Recommended Outcome of selected stimulus 0;1;-999 0 = selected stimulus loses; 1 = selected stimulus wins; -999 = subject missed resposne outcome
stimindex Integer Recommended ID of the Old/New stimulus in the set of all stimuli shown during the task
isfamiliar Integer Recommended Has the stimulus presented in an Old/New trial been seen before? 0;1 0 = New; 1 = Old
practice2 Integer Recommended Is the trial a practice trial? 0;1;-1 0 = main task; 1 = practice; -1 = memory test practice
Data Structure

This page displays the data structure defined for the measure identified in the title and structure short name. The table below displays a list of data elements in this structure (also called variables) and the following information:

  • Element Name: This is the standard element name
  • Data Type: Which type of data this element is, e.g. String, Float, File location.
  • Size: If applicable, the character limit of this element
  • Required: This column displays whether the element is Required for valid submissions, Recommended for valid submissions, Conditional on other elements, or Optional
  • Description: A basic description
  • Value Range: Which values can appear validly in this element (case sensitive for strings)
  • Notes: Expanded description or notes on coding of values
  • Aliases: A list of currently supported Aliases (alternate element names)
  • For valid elements with shared data, on the far left is a Filter button you can use to view a summary of shared data for that element and apply a query filter to your Cart based on selected value ranges

At the top of this page you can also:

  • Use the search bar to filter the elements displayed. This will not filter on the Size of Required columns
  • Download a copy of this definition in CSV format
  • Download a blank CSV submission template prepopulated with the correct structure header rows ready to fill with subject records and upload

Please email the The NDA Help Desk with any questions.