MODELS OF RATIO SCHEDULE PERFORMANCE

Predictions of P. R. Killeen's (1994) mathematical principles of reinf orcement were tested for responding on ratio reinforcement schedules. The type of response key, the number of sessions per condition, and fi rst vs. second half of a session had negligible effects on responding. Longer reinforcer durations and larger grain types engendered more re sponding, affecting primarily the parameter a (specific activation). K ey pecking was faster than treadle pressing, affecting primarily the p arameter delta (response time). Longer intertrial intervals led to hig her overall response rates and shorter postreinforcement pauses and hi gher running rates, and ruled out some competing explanations. The tre adle data required a distinction between the energetic requirements an d rate-limiting properties of extended responses. The theory was exten ded to predict pause durations and run rates on ratio schedules.