ABA Exam CoachLessons · C. Measurement, Data Display, and Interpretation
C.11 · Reading graphs: level, trend, variability
Your intervention data went up. So it worked, right? Not so fast. Let's learn to read a graph the way a behavior analyst does, and skip the most common trap people fall into.
Key takeaway
Within each phase, look at level, trend, and variability. Between phases, look at how fast the change shows up, how much the data overlap, and whether similar phases show the same pattern. If baseline was already moving in the expected direction, a higher intervention mean isn't evidence of an effect. And an A-B graph alone can't show a functional relation, because that takes prediction, verification, and replication.
Within each phase, look at level, trend, and variability. Between phases, look at how fast the change shows up, how much the data overlap, and whether similar phases show the same pattern. If baseline was already moving in the expected direction, a higher intervention mean isn't evidence of an effect. And an A-B graph alone can't show a functional relation, because that takes prediction, verification, and replication.
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.