Preference after training with differential changeover delays.

Williams, B. A. & Bell, M. C. (1999). Preference after training with differential changeover delays. Journal of the Experimental Analysis of Behavior, 71, 45-55.

Pigeons were trained on a multiple schedule in which each component consisted of concurrent variable- interval (VI) 30-s VI 60-s schedules. The two components of the multiple schedule differed only in terms of the changeover delays (COD): For one component short CODs were employed, and in the second component long CODs were used. After approximate matching was obtained in each component, probe tests involving new combinations of stimuli were presented (e.g., the VI 30-s schedule from each component) to determine how the different CODs affected preference. Despite shorter CODs producing higher changeover rates, the COD value had no systematic effect on preference on the probe trials. However, differences in reinforcement rate always produced preference for the schedule with the higher reinforcement rate. The results thus show that the the pattern of changeover behavior per se is not a critical determinant of choice in the probe-trial procedure.

Key words:choice, changeover delay, concurrent schedule, key peck, pigeons