ABSTRACT
This chapter defines intermittent reinforcement. It discusses four types of intermittent schedules for increasing and maintaining behavior: ratio schedules, simple interval schedules, schedules with limited hold, and duration schedules. Intermittent reinforcement is an arrangement in which a behavior is positively reinforced intermittently rather than every time it occurs. In a fixed-interval schedule, a reinforcer is presented following the first instance of a specific response after a fixed period of time. In a variable-interval schedule, a reinforcer is presented following the first instance of a specific response after an interval of time and the length of the interval changes unpredictably from one reinforcer to the next. A limited hold is a deadline for meeting the response requirement of a schedule of reinforcement. A limited hold can be added to any of the ratio or interval schedules. In a fixed-duration schedule, a reinforcer is presented only if a behavior occurs continuously for a fixed period of time.
