title: SubsMatch 2.0: Scanpath comparison and classification based on subsequence frequencies.
abstract: Our eye movements are driven by a continuous trade-off between the need for detailed examination of objects of interest and the necessity to keep an overview of our surrounding. In consequence, behavioral patterns that are characteristic for our actions and their planning are typically manifested in the way we move our eyes to interact with our environment. Identifying such patterns from individual eye movement measurements is however highly challenging. In this work, we tackle the challenge of quantifying the influence of experimental factors on eye movement sequences. We introduce an algorithm for extracting sequence-sensitive features from eye movements and for the classification of eye movements based on the frequencies of small subsequences. Our approach is evaluated against the state-of-the art on a novel and a very rich collection of eye movements data derived from four experimental settings, from static viewing tasks to highly dynamic outdoor settings. Our results show that the proposed method is able to classify eye movement sequences over a variety of experimental designs. The choice of parameters is discussed in detail with special focus on highlighting different aspects of general scanpath shape. Algorithms and evaluation data are available at: http://www.ti.uni-tuebingen.de/scanpathcomparison.html .
authors.affiliation: Universität of Tübingen, Sand 14, 72076, Tübingen, Germany. thomas.kuebler@uni-tuebingen.de.
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Kübler
authors.affiliation: Computer Engineering Department, University of Aalen, Anton-Huber-Strasse 23, 73430, Aalen, Germany.
authors.forename: Colleen
authors.initials: C
authors.lastname: Rothe
authors.affiliation: Computer Engineering Department, University of Aalen, Anton-Huber-Strasse 23, 73430, Aalen, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Schiefer
authors.affiliation: Universität of Tübingen, Sand 14, 72076, Tübingen, Germany.
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Rosenstiel
authors.affiliation: Universität of Tübingen, Sand 14, 72076, Tübingen, Germany.
authors.forename: Enkelejda
authors.initials: E
authors.lastname: Kasneci
mesh_terms: D000465:Algorithms; D053483:Eye Movement Measurements / Q000145:classification*; D005133:Eye Movements / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D010775:Photic Stimulation
keywords: Comparison; Eye movements; Eye tracking; Scan pattern; String kernel