A reversed partial-reinforcement effect.

The effects of partial- and continuous-reinforcement schedules were compared on both a between- and a within-Ss basis. Rats given either partial or continuous reinforcement in a lever-pressing situation (between-Ss comparison) showed the usual partial-reinforcement effects; both greater resistance to extinction and higher terminal acquisition response rates were associated with partial reinforcement. The same pattern of results did not, however, appear when a within-Ss comparison was made. Rats exposed to both continuous- and partial-reinforcement schedules showed higher terminal acquisition performance in the partialreinforcement condition, but showed greater resistance to extinction in the continuous-reinforcement condition.