Assessing preference for reinforcers using demand curves, work-rate functions, and expansion paths.

A BEHAVIORAL ECONOMIC MODEL THAT EXPLAINS THE CHOICE AND ALLOCATION OF WORK RATE IS USED TO PREDICT PERFORMANCE PATTERNS IN THREE CONTEXTS: with single schedules, with concurrent schedules when total reinforcement is low, and with concurrent schedules when reinforcement increases. Performance in the three contexts is predicted to change in orderly ways depending on how the subject evaluates the reinforcers earned. Quadrant diagrams are used to generate reinforcer demand functions, work-rate supply functions, and reinforcement-rate expansion paths. Preference between reinforcers is viewed as being a variable, with preference reversing in some situations.