Setting Appropriate Parameters for Event Detection in PyGaze Analyser (or Alternative Methods?)
I am conducting a psychological experiment and recording gaze data using a Tobii Pro Nano at 60Hz. Data collection was performed using Tobii Pro SDK in combination with Psychtoolbox, and I already have the recorded data. Each sample in the dataset contains a timestamp, a gaze coordinate on the screen for each eye, a pupil diameter for each eye, and validity indicators.
For event detection (blinks, fixations, saccades), I plan to use the detection functions provided in PyGaze Analyser’s `detectors.py`, specifically `blink_detection()`, `fixation_detection()`, and `saccade_detection()`. However, the function parameters are defined in pixels, and I would like to configure them in degrees of visual angle (dva) to match my experimental setup.
Specifically:
- What are appropriate threshold values for inter-sample displacement in fixation detection, and velocity and acceleration in saccade detection when defined in degrees of visual angle (dva)?
- Should the minimum number of consecutive samples (`minlen`) for blink detection and saccade detection be adjusted for a 60Hz sampling rate? If so, what values would be appropriate?
If there are alternative methods or tools that provide reliable event detection for gaze data, I would also be interested in learning about them.
Any recommendations or insights would be greatly appreciated.
Thank you for your time and consideration.