A reinforcement schedule where reinforcement is delivered after a varying amount of time has passed is called?

• A. Variable Interval
• B. Fixed Interval
• C. Fixed Ratio
• D. Variable Ratio

Answer: (A)

In operant conditioning, reinforcement schedules describe when rewards are given. If reinforcement happens after a changing amount of time has passed, the timing is unpredictable, which is characteristic of a variable interval schedule. This schedule yields a steady, moderate rate of responding because the learner can’t predict exactly when the next reward will come.

If it were a fixed interval, reinforcement would occur after a predictable, fixed time, often with bursts of responding near the interval’s end. If it were a fixed ratio, reinforcement would depend on a set number of responses, producing high responding with pauses after reinforcement. If it were a variable ratio, reinforcement would come after an unpredictable number of responses, yielding very high and steady responding with strong resistance to extinction.

So, the correct term is variable interval.