Fantino E, Herrnstein R J
J Exp Anal Behav. 1968 Jan;11(1):9-14. doi: 10.1901/jeab.1968.11-9.
Pigeons' pecks on either of two concurrently available response keys produced secondary reinforcers according to independent one-minute variable-interval schedules. Different secondary reinforcers, in the presence of which the rates of primary reinforcement were equal, were associated with each key. The rate of pecking maintained by each secondary reinforcer varied directly, but nonproportionally, with the number of primary reinforcements given in the presence of the secondary reinforcer.
鸽子对两个同时可用的反应键中的任何一个进行啄击,会根据独立的一分钟可变间隔时间表产生二级强化物。与每个按键相关联的是不同的二级强化物,在这些二级强化物出现时,一级强化的速率是相等的。每个二级强化物维持的啄击速率直接但不成比例地随二级强化物出现时给予的一级强化物数量而变化。