Fixation identification in centroid versus start-point modes using eye-tracking data
2008 (English)In: Perceptual and Motor Skills, ISSN 0031-5125, Vol. 106, no 3, 710-724 p.Article in journal (Refereed) Published
Fixation-identification algorithms, needed for analyses of eye movements, may typically be separated into three categories, viz. (i) velocity-based algorithms, (ii) area-based algorithms, and (iii) dispersion-based algorithms. Dispersion-based algorithms are commonly used but this application introduces some difficulties, one being optimization. Basically, there are two modes to reach this goal of optimization, viz., the start-point mode and the centroid mode. The aim of the present study was to compare and evaluate these two dispersion-based algorithms. Manual inspections were made of 1,400 fixations in each mode. Odds ratios showed that by using the centroid mode for fixation detection, a valid fixation is 2.86 times more likely to be identified than by using the start-point mode. Moreover, the algorithm based on centroid mode dispersion showed a good interpretation speed, accuracy, robustness, and ease of implementation, as well as adequate parameter settings.
Place, publisher, year, edition, pages
2008. Vol. 106, no 3, 710-724 p.
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:liu:diva-15915DOI: 10.2466/PMS.106.3.710-724PubMedID: 18712192OAI: oai:DiVA.org:liu-15915DiVA: diva2:128343