Effect of Frequency and Probability of Reward on Choice

Abstract

In studies of probability and simultaneous discrimination learning choice is typically to the alternative with higher probability of reinforcement. However, in these situations probability of reinforcement is confounded with frequency of reinforcement, since the alternative with higher probability of reinforcement given a response also typically receives a greater absolute number of reinforcements in each session. In the present study pigeons were given separate stimulus training on two keys, with only one key presented on each trial, and numbers of trials and probabilities of reinforcement on each key manipulated to examine separately the effects of frequency of reinforcement and probability of reinforcement in different groups. Choice was examined on choice trials with both keys presented. When frequency and probability of reinforcement were manipulated independently, each of these variables affected choice.