title: The roles of stimulus and response uncertainty in forced-choice performance: an amendment to Hick/Hyman Law.
abstract: Hick/Hyman Law describes one of the core phenomena in the study of human information processing: mean response time is a linear function of average uncertainty. In the original work of Hick, (1952) and Hyman, (1953), along with many follow-up studies, uncertainty regarding the stimulus and uncertainty regarding the response were confounded such that the relative importance of these two factors remains mostly unknown. The present work first replicates Hick/Hyman Law with a new set of stimuli and then goes on to separately estimate the roles of stimulus and response uncertainty. The results demonstrate that, for a popular type of task-visual stimuli mapped to vocal responses-response uncertainty accounts for a majority of the effect. The results justify a revised expression of Hick/Hyman Law and place strong constraints on theoretical accounts of the law, as well as models of response selection in general.
authors.affiliation: Department of Psychology, University of Iowa, E11 Seashore Hall, Iowa City, IA, 52241, USA. twifall@gmail.com.
authors.forename: Tim
authors.identifier: http://orcid.org/0000-0002-5331-085X
authors.initials: T
authors.lastname: Wifall
authors.affiliation: Department of Psychology, University of Iowa, E11 Seashore Hall, Iowa City, IA, 52241, USA.
authors.forename: Eliot
authors.initials: E
authors.lastname: Hazeltine
authors.affiliation: Department of Psychology, University of Iowa, E11 Seashore Hall, Iowa City, IA, 52241, USA.
authors.forename: J
authors.initials: J
authors.lastname: Toby Mordkoff
mesh_terms: D002755:Choice Behavior; D004192:Discrimination, Psychological / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008960:Models, Psychological; D011930:Reaction Time / Q000502:physiology*; D035501:Uncertainty