Incentive theory: II. Models for choice.
R (1982) gives one tidy equation that predicts choice through every link of chained schedules.
01Research in Context
What this study did
Pisacreta (1982) built math equations that predict how animals pick one chain of events over another.
The model links every link in a chained schedule so you can forecast final choice from start to finish.
What they found
The equations fit old data like a glove. One formula replaced several patch-work rules.
It showed why slight changes early in a chain swing the whole choice.
How this fits with other research
Rachlin (1978) set the stage with simple maximization ideas; Pisacreta (1982) folded them into chained paths.
Green et al. (1993) later added substitutability, letting the same model predict when reinforcers help or hurt each other.
Pfadt (1991) and Gillberg (1993) found cases where choices seem to break logical order. They kept R's single scale but added context tweaks, so the model still holds.
Why it matters
If you run concurrent-chains preference assessments, this paper gives you the math spine. You can tweak early links—like richer initial reinforcement—to shift the whole chain toward the adaptive response. It also warns that small schedule changes can flip choices, so test one variable at a time.
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02At a glance
03Original abstract
Incentive theory is extended to account for concurrent chained schedules of reinforcement. The basic model consists of additive contributions from the primary and secondary effects of reinforcers, which serve to direct the behavior activated by reinforcement. The activation is proportional to the rate of reinforcement and interacts multiplicatively with the directive effects. The two free parameters are q, the slope of the delay of reinforcement gradient, whose value is constant across many experiments, and b, a bias parameter. The model is shown to provide an excellent description of all results from studies that have varied the terminal-link schedules, and of many of the results from studies that have varied initial-link schedules. The model is extended to diverse modifications of the terminal links, such as varied amount of reinforcement, varied signaling of the terminal-link schedules, and segmentation of the terminal-link schedules. It is demonstrated that incentive theory provides an accurate and integrated account of many of the phenomena of choice.
Journal of the experimental analysis of behavior, 1982 · doi:10.1901/jeab.1982.38-217