Abstract When reinforcer rates are manipulated in within-subjects designs, persistence in subsequent extinction trials is sometimes greater to the response alternative associated with the higher reinforcer rate (“reversed” partial reinforcement extinction effect, RPREE). The RPREE is often held to be a contradiction to the conventional PREE. To explore the interaction between these effects, student subjects were exposed to a multiple high-density and low-density reinforcement schedule, then to extinction conditions. Subjects in two control conditions received the high- and low-density schedules only. For all groups, general extinction persistence was elevated, and a within-subjects RPREE occurred under the multiple schedule. The RPREE was caused by the low-density component increasing persistence to the high-density component; the high-density component did not decrease persistence to the low-density component. These results support the view that the RPREE may be a within-subjects effect of the conventional PREE.