摘要:Few studies have evaluated ways to thin punishment schedules. The purpose of this study was to examine the effects of using variable ratio (VR) schedules to thin the time-out schedule gradually. Warnings were used in some conditions to assist potentially with schedule thinning, but this analysis was limited. Participants were 3 young students who engaged in problem behavior during enriched time-in periods. Dense schedules of intermittent time-out were effective at reducing problem behavior. Key words: time-out, schedule thinning, intermittent punishment