Inter‐reinforcement Times for the Bar‐pressing Response of White Rats on Two DRL Schedules1,2

A knowledge of inter-reinforcement times (IS(R)T) seems of interest because, among other reasons, they bear on the variable of "reinforcement density" in behavior theory. IS(R)T data were here recorded for bar-pressing responses by two white rats working on DRL 10 sec and DRL 40 sec. Sample inter-response time (IRT) distributions and cumulative records were taken simultaneously for comparison purposes. IS(R)T sequences and distributions have certain characteristics that urge further investigation.