What schedule of reinforcement provides rewards after a specified time period?

A fixed interval schedule of reinforcement provides rewards after a specified time period. In this type of schedule, reinforcement is delivered after a consistent and predictable duration of time has passed, as long as the desired behavior has occurred at least once during that interval. This means that the individual learns to associate the passage of time with the potential for receiving a reward.

For example, if a person receives a paycheck every two weeks (which is a set time period), their behavior related to work can be reinforced by this fixed interval. They know that regardless of their performance, as long as they work through the two-week period, they will receive their paycheck.

This contrasts with variable intervals, where reinforcement occurs after an unpredictable amount of time, adding an element of randomness that can lead to high rates of responding since the timing of the reward is not fixed. Similarly, fixed ratio and variable ratio schedules are based on the number of behaviors performed, rather than the time elapsed. In fixed ratio schedules, a specific number of responses must occur to receive reinforcement, while variable ratio schedules require an unpredictable number of responses. Thus, the concept of a specific time period is distinct to the fixed interval schedule.