title: Steady-state choice between four alternatives obeys the constant-ratio rule.
abstract: We investigated why violations to the constant-ratio rule, an assumption of the generalized matching law, occur in procedures that arrange frequent changes to reinforcer ratios. Our investigation produced steady-state data and compared them with data from equivalent, frequently changing procedures. Six pigeons responded in a four-alternative concurrent-schedule experiment with an arranged reinforcer-rate ratio of 27:9:3:1. The same four variable-interval schedules were used in every condition, for 50 sessions, and the physical location of each schedule was changed across conditions. The experiment was a steady-state version of a frequently changing procedure in which the locations of four VI schedules were changed every 10 reinforcers. We found that subjects' responding was consistent with the constant-ratio rule in the steady-state procedure. Additionally, local analyses showed that preference after reinforcement was towards the alternative that was likely to produce the next reinforcer, instead of being towards the just-reinforced alternative as in frequently changing procedures. This suggests that the effect of a reinforcer on preference is fundamentally different in rapidly changing and steady-state environments. Comparing this finding to the existing literature suggests that choice is more influenced by reinforcer-generated signals when the reinforcement contingencies often change.
authors.affiliation: The University of Auckland.
authors.forename: Joshua
authors.initials: J
authors.lastname: Bensemann
authors.affiliation: The University of Auckland.
authors.forename: Brenda
authors.initials: B
authors.lastname: Lobb
authors.affiliation: The University of Auckland.
authors.forename: Christopher A
authors.initials: CA
authors.lastname: Podlesnik
authors.affiliation: The University of Auckland.
authors.forename: Douglas
authors.initials: D
authors.lastname: Elliffe
mesh_terms: D000818:Animals; D002755:Choice Behavior; D010856:Columbidae; D003216:Conditioning, Operant; D012055:Reinforcement Schedule; D012054:Reinforcement, Psychology
keywords: choice; concurrent schedules; constant-ratio rule; generalized matching; reinforcer rate; steady-state