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getting_started:eyelink [2017/08/17 11:21]
127.0.0.1 external edit
getting_started:eyelink [2018/09/12 11:19] (current)
131.174.46.108 [EDF data - pupil]
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 ====EDF data - pupil==== ====EDF data - pupil====
 Pupil size data can be recorded as '​area'​ or '​diameter'​ in pixels. The area is recorded in scaled image pixels. Diameter is calculated from pupil area fit using a circle model. Pupil size data can be recorded as '​area'​ or '​diameter'​ in pixels. The area is recorded in scaled image pixels. Diameter is calculated from pupil area fit using a circle model.
 +Note that when pupil diameter is your variable of interest, you should correct for viewing direction. When the eye rotates away from the camera during viewing, the pupil seems smaller. This effect can be corrected for with a geometrical model described by [[https://​www.ncbi.nlm.nih.gov/​pubmed/​25953668|Hayes and Petrov (2016)]], but this requires that you know the geometry of the eye tracking camera relative to the eye and the computer screen. Alternatively,​ you could use ft_regressconfound to try and remove the influence of viewing direction on pupil diameter.
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 ====Mapping to Presentation Stimuli==== ====Mapping to Presentation Stimuli====