Run Length, Visit Duration, And Reinforcers Per Visit In Concurrent Performance

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generalized matching law, scheduled reinforcer probability, scheduled reinforcer rate, run length, visit duration, lever press, rats


Psychology | Social and Behavioral Sciences


The contingencies in each alternative of concurrent procedures consist of reinforcement for staying and reinforcement for switching. For the stay contingency, behavior directed at one alternative earns and obtains reinforcers. For the switch contingency, behavior directed at one alternative earns reinforcers but behavior directed at the other alternative obtains them. In Experiment 1, responses on the main lever, in S1, incremented stay and switch schedules and obtained a stay reinforcer when it became available. Responses on the switch lever changed S1 to S2 and obtained switch reinforcers when available. In S2, neither responses on the main lever nor on the switch lever were reinforced, but a switch response changed S2 to S1. Run lengths and visit durations were a function of the ratio of the scheduled probabilities of reinforcement (staying/switching). From run lengths and visit durations, traditional concurrent performance was synthesized, and that synthesized performance was consistent with the generalized matching law. Experiment 2 replicated and extended this analysis to concurrent variable-interval schedules. The synthesized results challenge any theory of matching that requires a comparison among the alternatives.

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APA Citation: MacDonall, J.S. (1998). Run length, visit duration, and reinforcers per visit in concurrent performance. Journal of the Experimental Analysis of Behavior, 69(3), 275-293.