Pigeons’ preference for fixed-interval over fixed-ratio food reinforcement schedules

Abstract

Pigeons tested on reinforcement schedules that terminated in the same reinforcer preferred fixed-interval (FI) over fixed-ratio (FR) schedules, even when the response (i.e., work) requirements of the schedules were equal and rate of reinforcement on the FR schedule was double that of the FI. Only when rate of reinforcement on the FR schedule was 2.15 times greater than rate of reinforcement on the FI schedule did subjects prefer the FR over the FI schedule. Reinforcement schedule preferences appear to be directly sensitive to time-dependent vs. nontemporal variables, rate of reinforcement parameters, and magnitude of the total response demand placed upon the organism, in that order of importance.