Some effects on generalization gradients of tandem schedules

The relationship between training conditions and stimulus generalization gradients was examined using tandem schedules of reinforcement. Schedules were selected so that frequency of reinforcement and rate of responding were varied somewhat independently of each other. A peak-shift in the generalization gradient was obtained when extinction had been associated with one of the stimuli. No comparable peak shift was obtained when there were equal response rates in the training stimuli even with dissimilar frequencies of reinforcement. The data imply that response rates at the end of training, rather than reinforcement frequency per se, determine the characteristics of the generalization gradient.