Mathematical analysis of the durations of reinforced inter-response times during variable interval reinforcement

In a free-responding situation in which reinforcements are scheduled by a variable interval program, the durations of reinforced inter-response times are shown to be a function of the durations of all inter-response times produced by S and of the frequency of reinforcement.Based on a portion of the author's doctoral dissertation, and supported in part by an NIMH predoctoral research fellowship. Suggestions by W. K. Estes increased the intelligibility of this paper.