Variable interval schedules of reinforcement occur under which condition?

Variable interval schedules of reinforcement are characterized by the delivery of reinforcement after the first response occurs following a varying amount of time. This means that the time intervals between reinforcements are not consistent; instead, they change unpredictably.

When a variable interval schedule is implemented, a reinforcement is available after an unpredictable amount of time has passed. This variability encourages consistent responding because the individual cannot predict exactly when the reinforcement will occur, which often leads to steady rates of response over time.

For instance, a teacher may provide praise to a student after varying amounts of time, like every 3 minutes on one occasion, then every 7 minutes on another. The unpredictability of the time interval keeps the student engaged and anticipating the reinforcement, motivating them to respond regularly during the time window.

In contrast, other schedules of reinforcement, such as fixed interval or ratio schedules, are based on predictable time frames or straightforward counts of behavior, which does not align with the inherent characteristics of variable interval schedules.