title: A probabilistic multidimensional model of location information.
abstract: A probabilistic multidimensional model of location discrimination is developed and applied to data from an experiment in which subjects are required to determine whether a briefly presented horizontal and vertical bar are touching. The proposed gap-detection model assumes that errors in perception are due to variability in the perceived location and/or in the perceived length of the bars. A series of gap-detection models that allow variability only in perceived location were rejected on the basis of likelihood-ratio tests of overall goodness of fit. However, when the models were modified to account for: (a) a compression of the distance perceived between the bars (Wolford, 1975), or (b) the bisection illusion (Künnapas, 1955), excellent absolute fits to the data were obtained. A pair of models that suggests that the horizontal/vertical illusion or a response bias was operative failed. Applications of the model to more conventional object-perception experiments (e.g., the illusory-conjunction experiment) are discussed.
authors.affiliation: Estes Lab, Department of Psychology, Harvard University, Cambridge, MA 02138.
authors.forename: W T
authors.initials: WT
authors.lastname: Maddox
authors.forename: W
authors.initials: W
authors.lastname: Prinzmetal
authors.forename: R B
authors.initials: RB
authors.lastname: Ivry
authors.forename: F G
authors.initials: FG
authors.lastname: Ashby
mesh_terms: D000328:Adult; D001288:Attention; D005260:Female; D006801:Humans; D008297:Male; D015233:Models, Statistical; D009903:Optical Illusions; D009949:Orientation; D010364:Pattern Recognition, Visual; D011336:Probability; D011601:Psychophysics