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Element Icon Velocity Threshold Estimator
Category: Eye-tracking Analysis AddIn: Eye-tracking analysis
Creator: OkazoLab Scope: Parent event
Owns Snippets: None Usage: Snippets


NameDescription                              ConstraintsTypeOn
Estimator Parameters
Is Estimating        Defines whether the threshold estimation is going on. Assign false to pause the estimation.                Boolean         
Lambda        Defines the multiplication factor for the standard deviation of velocity distribution. The result of the multiplication is used as the velocity threshold.                Double         
Gaze Processing
Tracking Device        Defines what tracking device provides positional samples for the element. The tracking devices include eye-trackers, the mouse and touch-screens. The 'Auto' option chooses the tracking device selected in the parent event. If there are no tracking elements enabled in the experiment, the system mouse is always used.                String         
Sampling Rate        Defines the sampling rate of the tracking device  hardware in Hz. Keep the zero value for auto-detection.                Double         
Analysis Window Size        Defines the size of a moving analysis window in samples. The value also defines the data range in all generated plots                Int32         
Exclusive Thresholds        Defines whether the exclusive velocity and saccade duration thresholds are used for the fixation detection by this element. The default value is false, which means that the same threshold values are shared with all eye-tracking analysis elements.                Boolean         
X Velocity Threshold        Defines the saccade velocity threshold for the X-axes                Double         
Y Velocity Threshold        Defines the saccade velocity threshold for the Y-axes                Double         
Element AOI        Selects a visual element, whose viewport defines an on-screen AOI for the eye-tracking analysis.                Int32         
Custom AOIs        Selects a visual element, whose viewport defines an on-screen AOI for the eye-tracking analysis.                IColle..         
General Plot Settings
Rendering Size        The rendering size also defines the image resolution, when the plot is saved into an image file or video.                clSize         
Plot Title        Defines the title shown on the plot. The empty title removes the title area on the plot                String         
Show Axis        Defines whether the axis are visible on the plot                Boolean         
Show Gridlines        Defines whether the major tick gridlines are shown on the plot.                Boolean         
Add Screen Clone        Defines whether a clone of the presentation screen is shown at the background of the plot.                enScre..         
Rendering Quality        Defines the quality and speed the plot rendering                Int32         
Plot Theme        Defines a visual theme for the plot                Int32         
Velocity Plot Settings
Threshold Color                        stColor         
Fixation Line Color                        stColor         
Line Thickness                        Double         
Saccade Line Color                        stColor         
Reset Plot Now        Runtime command that resets the plotted data.                Boolean         
XAML Velocity Plot        Returns a live XAML control that can be used for direct binding to the Content property of the XAML ContentControl element, e.g. ContentControl with a generated staircase plot can be added to the status screen or to the XAML Layout element.                UIElem..         
Save Velocity Plot Now        Assign a filename to save the generated plot at runtime                String         
Preview Velocity Plot        Open a window with the plot preview                Boolean         
Is Enabled        If set to false the element is completely omitted when the experiment is run                Boolean         
Title        Title of the element                String         

Velocity Threshold Estimator Element automatically estimates the saccade threshold over the current eye-tracking data and its noise. The estimated threshold can be then used by other eye-tracking analysis elements in an experiment.

Demo Video


Snapshot 1

Snapshot 1

Snapshot 2

Snapshot 2

Practical Use


Technique 1

  1. Step 1
  2. Step 2
    === Technique 2 ===
  3. Step 1
  4. Step 2

     // Check the trial outcome. Result and RT just other user variables
    // insert code snippet here..
    == Notes ==
  5. Insert Notes here..
  6. Insert Notes here..


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