Pigeons' choices between fixed-ratio and linear or geometric escalating schedules

Area of Science:

• Behavioral Psychology
• Animal Cognition
• Operant Conditioning

Background:

• Investigating principles of choice behavior is crucial for understanding decision-making under varying conditions.
• Previous research explored choice patterns using fixed-ratio and progressive-ratio schedules.

Purpose of the Study:

• To compare the linear-optimality principle with the sums-of-reciprocals principle.
• To assess the generality of the sums-of-reciprocals principle in diminishing returns situations.
• To examine the impact of different escalation patterns and initial values in progressive-ratio schedules.

Main Methods:

• Pigeons made choices between fixed-ratio and progressive-ratio schedules.
• Progressive-ratio schedules featured either constant increments or proportional increments.
• The initial value of the progressive alternative was systematically manipulated.

Main Results:

• Pigeon choice patterns were consistently described by the sums-of-reciprocals principle across various conditions.
• This held true irrespective of the initial/reset value and the type of escalation (linear or proportional).
• One phase showed a deviation, but overall the principle demonstrated strong predictive power.

Conclusions:

• The sums-of-reciprocals principle is a robust descriptor of choice behavior in pigeons facing diminishing returns.
• This principle effectively explains behavior with both fixed-increment and proportional progressive schedules.
• The findings suggest that the valuation of reinforcers is influenced by their relative proximity to the choice point.