MAD saccade: statistically robust saccade threshold estimation via the median absolute deviation
Saccade detection is a critical step in the analysis of gaze data. A common method for saccade detection is to use a simple threshold for velocity or acceleration values, which can be estimated from the data using the mean and standard deviation. However, this method has the downside of being influe...
Saved in:
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2020-05-01
|
| Series: | Journal of Eye Movement Research |
| Subjects: | |
| Online Access: | https://bop.unibe.ch/JEMR/article/view/5992 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1850189717940731904 |
|---|---|
| author | Benjamin Voloh Marcus R Watson Seth Konig Thilo Womelsdorf |
| author_facet | Benjamin Voloh Marcus R Watson Seth Konig Thilo Womelsdorf |
| author_sort | Benjamin Voloh |
| collection | DOAJ |
| description | Saccade detection is a critical step in the analysis of gaze data. A common method for saccade detection is to use a simple threshold for velocity or acceleration values, which can be estimated from the data using the mean and standard deviation. However, this method has the downside of being influenced by the very signal it is trying to detect, the outlying velocities or accelerations that occur during saccades. We propose instead to use the median absolute deviation (MAD), a robust estimator of dispersion that is not influenced by outliers. We modify an algorithm proposed by Nyström and colleagues, and quantify saccade detection performance in both simulated and human data. Our modified algorithm shows a significant and marked improvement in saccade detection - showing both more true positives and less false negatives – especially under higher noise levels. We conclude that robust estimators can be widely adopted in other common, automatic gaze classification algorithms due to their ease of implementation. |
| format | Article |
| id | doaj-art-211d9d284a37459cb63bb3cbf1d7b511 |
| institution | OA Journals |
| issn | 1995-8692 |
| language | English |
| publishDate | 2020-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Journal of Eye Movement Research |
| spelling | doaj-art-211d9d284a37459cb63bb3cbf1d7b5112025-08-20T02:15:33ZengMDPI AGJournal of Eye Movement Research1995-86922020-05-0112810.16910/jemr.12.8.3MAD saccade: statistically robust saccade threshold estimation via the median absolute deviationBenjamin Voloh0Marcus R Watson1Seth Konig2Thilo Womelsdorf3Vanderbilt UniversityYork UniversityVanderbilt UniversityVanderbilt UniversitySaccade detection is a critical step in the analysis of gaze data. A common method for saccade detection is to use a simple threshold for velocity or acceleration values, which can be estimated from the data using the mean and standard deviation. However, this method has the downside of being influenced by the very signal it is trying to detect, the outlying velocities or accelerations that occur during saccades. We propose instead to use the median absolute deviation (MAD), a robust estimator of dispersion that is not influenced by outliers. We modify an algorithm proposed by Nyström and colleagues, and quantify saccade detection performance in both simulated and human data. Our modified algorithm shows a significant and marked improvement in saccade detection - showing both more true positives and less false negatives – especially under higher noise levels. We conclude that robust estimators can be widely adopted in other common, automatic gaze classification algorithms due to their ease of implementation.https://bop.unibe.ch/JEMR/article/view/5992Saccadesmedian absolute deviationMADeye trackinghead-free viewing |
| spellingShingle | Benjamin Voloh Marcus R Watson Seth Konig Thilo Womelsdorf MAD saccade: statistically robust saccade threshold estimation via the median absolute deviation Journal of Eye Movement Research Saccades median absolute deviation MAD eye tracking head-free viewing |
| title | MAD saccade: statistically robust saccade threshold estimation via the median absolute deviation |
| title_full | MAD saccade: statistically robust saccade threshold estimation via the median absolute deviation |
| title_fullStr | MAD saccade: statistically robust saccade threshold estimation via the median absolute deviation |
| title_full_unstemmed | MAD saccade: statistically robust saccade threshold estimation via the median absolute deviation |
| title_short | MAD saccade: statistically robust saccade threshold estimation via the median absolute deviation |
| title_sort | mad saccade statistically robust saccade threshold estimation via the median absolute deviation |
| topic | Saccades median absolute deviation MAD eye tracking head-free viewing |
| url | https://bop.unibe.ch/JEMR/article/view/5992 |
| work_keys_str_mv | AT benjaminvoloh madsaccadestatisticallyrobustsaccadethresholdestimationviathemedianabsolutedeviation AT marcusrwatson madsaccadestatisticallyrobustsaccadethresholdestimationviathemedianabsolutedeviation AT sethkonig madsaccadestatisticallyrobustsaccadethresholdestimationviathemedianabsolutedeviation AT thilowomelsdorf madsaccadestatisticallyrobustsaccadethresholdestimationviathemedianabsolutedeviation |