title: Empirical validation of a procedure to correct position and stimulus biases in matching-to-sample.
abstract: The development of position and stimulus biases often occurs during initial training on matching-to-sample tasks. Furthermore, without intervention, these biases can be maintained via intermittent reinforcement provided by matching-to-sample contingencies. The present study evaluated the effectiveness of a correction procedure designed to eliminate both position and stimulus biases. Following key-peck training, a group of 6 pigeons had extended exposure to matching-to-sample contingencies without a correction procedure, a group of 4 pigeons was briefly exposed to a simultaneous matching-to-sample procedure to assess biases prior to exposure to the correction procedure, and a group of 5 pigeons was exposed directly to the correction procedure. The correction procedure arranged that every time an incorrect match was made, the trial configuration was repeated on the subsequent trial until a correct match was made. Extended exposure to matching-to-sample contingencies without a correction procedure was associated with reduced biases eventually for most subjects, but rapid development of near-perfect accuracy and bias-free performance was observed upon the implementation of the correction procedure regardless of the type of bias. Bias-free performance was maintained following subsequent exposure to a zero-delay MTS procedure.
authors.affiliation: Department of Psychology, University of Florida, P.O. Box 112250, Gainesville, FL 32611-2250, USA. kangas@ufl.edu
authors.forename: Brian D
authors.initials: BD
authors.lastname: Kangas
authors.forename: Marc N
authors.initials: MN
authors.lastname: Branch
mesh_terms: D000818:Animals; D001522:Behavior, Animal; D010856:Columbidae; D003216:Conditioning, Operant; D036262:Empirical Research; D008297:Male