A new comprehensive eye-tracking test battery concurrently evaluating the Pupil Labs glasses and the EyeLink 1000

Abstract

Eye-tracking experiments rely heavily on good data quality of eye-trackers. Unfortunately, it is often the case that only the spatial accuracy and precision values are available from the manufacturers. These two values alone are not sufficient to serve as a benchmark for an eye-tracker: Eye-tracking quality deteriorates during an experimental session due to head movements, changing illumination or calibration decay. Additionally, different experimental paradigms require the analysis of different types of eye movements; for instance, smooth pursuit movements, blinks or microsaccades, which themselves cannot readily be evaluated by using spatial accuracy or precision alone. To obtain a more comprehensive description of properties, we developed an extensive eye-tracking test battery. In 10 different tasks, we evaluated eye-tracking related measures such as: the decay of accuracy, fixation durations, pupil dilation, smooth pursuit movement, microsaccade classification, blink classification, or the influence of head motion. For some measures, true theoretical values exist. For others, a relative comparison to a reference eye-tracker is needed. Therefore, we collected our gaze data simultaneously from a remote EyeLink 1000 eye-tracker as the reference and compared it with the mobile Pupil Labs glasses. As expected, the average spatial accuracy of 0.57° for the EyeLink 1000 eye-tracker was better than the 0.82° for the Pupil Labs glasses (N = 15). Furthermore, we classified less fixations and shorter saccade durations for the Pupil Labs glasses. Similarly, we found fewer microsaccades using the Pupil Labs glasses. The accuracy over time decayed only slightly for the EyeLink 1000, but strongly for the Pupil Labs glasses. Finally, we observed that the measured pupil diameters differed between eye-trackers on the individual subject level but not on the group level. To conclude, our eye-tracking test battery offers 10 tasks that allow us to benchmark the many parameters of interest in stereotypical eye-tracking situations and addresses a common source of confounds in measurement errors (e.g., yaw and roll head movements). All recorded eye-tracking data (including Pupil Labs’ eye videos), the stimulus code for the test battery, and the modular analysis pipeline are freely available (https://github.com/behinger/etcomp).

Rivalry Onset in and around the Fovea: The Role of Visual Field Location and Eye Dominance on Perceptual Dominance Bias

“…The spatial accuracy of the EyeLink 1000 (SR Research Ltd., Mississauga, Ontario, Canada) is 0.5 degrees [35]. Given the small separation of stimuli, we are unable to determine if saccades were made to stimuli at 0.38º eccentricity.…”

Neurogastronomy as a Tool for Evaluating Emotions and Visual Preferences of Selected Food Served in Different Ways

“…Ensuring the quality of eye movement data was based on adherence to several aspects, including the suitability of the equipment used [ 30 ], equipment settings, experimental procedure, and the behavior and psychology of participants [ 31 , 32 , 33 ].…”

“…The determination of the time interval was based on other studies [37] looking at the attention range of the participants. The subject of interest during the first 15 s was the Ensuring the quality of eye movement data was based on adherence to several aspects, including the suitability of the equipment used [30], equipment settings, experimental procedure, and the behavior and psychology of participants [31][32][33].…”

Eye Movements and Fixation-Related Potentials in Reading: A Review

“…Despite the existing challenges associated with simultaneously recording EMs and ERPs (see [26,[88][89][90][91] for a discussion), joint efforts from the international research community, alongside technological advances (see [92][93][94][95] for a discussion) and advances in computational algorithms used for the correction of ocular artifacts [26,[96][97][98][99], have allowed for a third, ongoing, phase of co-registration research to become possible. These studies have involved simultaneously recording EM and ERP data from the same group of participants, reading the same stimuli, and performing the same task.…”