title: A quantitative confidence signal detection model: 1. Fitting psychometric functions.
abstract: Perceptual thresholds are commonly assayed in the laboratory and clinic. When precision and accuracy are required, thresholds are quantified by fitting a psychometric function to forced-choice data. The primary shortcoming of this approach is that it typically requires 100 trials or more to yield accurate (i.e., small bias) and precise (i.e., small variance) psychometric parameter estimates. We show that confidence probability judgments combined with a model of confidence can yield psychometric parameter estimates that are markedly more precise and/or markedly more efficient than conventional methods. Specifically, both human data and simulations show that including confidence probability judgments for just 20 trials can yield psychometric parameter estimates that match the precision of those obtained from 100 trials using conventional analyses. Such an efficiency advantage would be especially beneficial for tasks (e.g., taste, smell, and vestibular assays) that require more than a few seconds for each trial, but this potential benefit could accrue for many other tasks.
authors.affiliation: Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts; and Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts.
authors.forename: Yongwoo
authors.initials: Y
authors.lastname: Yi
authors.affiliation: Jenks Vestibular Physiology Laboratory, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts; and Department of Otolaryngology, Harvard Medical School, Boston, Massachusetts dan_merfeld@meei.harvard.edu.
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Merfeld
mesh_terms: D006801:Humans; D057230:Limit of Detection; D008959:Models, Neurological; D011336:Probability; D011594:Psychometrics / Q000379:methods / Q000592:standards; D012684:Sensory Thresholds
keywords: confidence calibration; confidence rating; decision-making; thresholds