ABA Exam CoachLessons · B. Concepts and Principles
B.9 · Simple schedules of reinforcement
FR, VR, FI, VI: four schedules that sound alike, but you can sort out every one of them with just two quick questions. Let's learn those questions so you never mix them up again!
Key takeaway
First ask whether the rule counts responses (ratio) or time followed by one response (interval). Then ask whether the requirement is the same every time (fixed) or varies around an average (variable). On an interval schedule, the passing time only makes the reinforcer available, and the first response after it is what gets reinforced. If no response is needed at all, it's fixed time or variable time, not an interval schedule.
First ask whether the rule counts responses (ratio) or time followed by one response (interval). Then ask whether the requirement is the same every time (fixed) or varies around an average (variable). On an interval schedule, the passing time only makes the reinforcer available, and the first response after it is what gets reinforced. If no response is needed at all, it's fixed time or variable time, not an interval schedule.
Members get the full lesson video, notes and a 5-question test
The video walks through the idea, worked examples, the trap people fall into and an exam-style question. The notes and the checkpoint come with it, and your results feed your Where to focus plan.