jspsych-free-sort plugin

The free-sort plugin displays a collection of images on the screen that the subject can interact with by clicking and dragging. All of the moves that the subject performs are recorded.

Parameters

This table lists the parameters associated with this plugin. Parameters with a default value of undefined must be specified. Other parameters can be left unspecified if the default value is acceptable.

Parameter Type Default Value Description
stimuli array undefined Each element of this array is an image path.
stim_height numeric 100 The height of the images in pixels.
stim_width numeric 100 The width of the images in pixels.
sort_area_height numeric 800 The height of the container that subjects can move the stimuli in. Stimuli will be constrained to this area.
sort_area_width numeric 800 The width of the container that subjects can move the stimuli in. Stimuli will be constrained to this area.
prompt string "" This string can contain HTML markup. The intention is that it can be used to provide a reminder about the action the subject is supposed to take (e.g. which key to press).
prompt_location string "above" Indicates whether to show the prompt "above" or "below" the sorting area.

Data Generated

In addition to the default data collected by all plugins, this plugin collects the following data for each trial.

Name Type Value
init_locations JSON string A JSON-encoded object representing the initial locations of all the stimuli in the sorting area. The object is an array with one element per stimulus. Each element in the array has a "src", "x", and "y" value. "src" is the image path, and "x" and "y" are the object location.
moves JSON string A JSON-encoded object representing all of the moves the participant made when sorting. The object is an array with each element representing a move. Each element in the array has a "src", "x", and "y" value. "src" is the image path, and "x" and "y" are the object location after the move.
final_locations JSON string A JSON-encoded object representing the final locations of all the stimuli in the sorting area. The object is an array with one element per stimulus. Each element in the array has a "src", "x", and "y" value. "src" is the image path, and "x" and "y" are the object location.
rt numeric The response time in milliseconds for the subject to finish all sorting.

Examples

Basic example

var sorting_stimuli = [];
for (var i = 1; i <= 12; i++) {
    sorting_stimuli.push("img/cell_img_" + i + ".jpg");
}

var sort_trial = {
    type: 'free-sort',
    stimuli: sorting_stimuli,
    prompt: "<p>Click and drag the images below to sort them so that similar items are close together.</p>"
};