AN AUTO-ADJUSTING SHAPING PROCEDURE

A variable interval (VI) schedule is described that automatically adju sts the programmed rates of reinforcement in accordance with the rates of responding of subjects during the two immediately preceding 30-sec time intervals. The schedule prescribes that as rate of responding de creases, programmed reinforcement rate increases, and that when rate o f responding increases, reinforcement rate decreases. Thus, programmed reinforcement rate is adjusted continuously until some target value i s reached. Ten rats were exposed to this procedure five times a day at l-h intervals. The target, set at VI 120 sec, was reached by most sub jects within 4 days of training. Subsequently, all subjects responded consistently during five daily l-h sessions with VI 120 sec. This proc edure speeds up the training of subjects on long VI schedules and subs tantially reduces the time and effort spent observing the subjects and adjusting the schedule parameter value during the early development o f responding.