The precision of eye-trackers: a case for a new measure

Abstract

Several possible measures for the precision of an eye-tracker exist. The fact that the commonly used measures of standard deviation and RMS lack with respect to their ability to produce replicable results with varying frame rate, gaze distance and arrangement of samples within a fixation, makes it difficult to compare eye-trackers. It is proposed that an area-based measure, BCEA, is adapted to provide a one dimensional quantity that is intuitive, independent of frame rate and sensitive to small jerks in the reported fixation position.