An intervention might cause an immediate change in the level of the behavior, but often an intervention changes the slope of the behavior. The slope is the overall direction that the behavior takes over time. You might remember from middle school that the slope of a line is the rise—or the change in Y value—divided by the run—or the change in time. In this graph, about 12 responses occur during the first session. In the second session, about 14 responses occurred, and during the third, there were about 16 responses. Each day the student is engaging in two more responses than she did on the day before. This behavior has an increasing slope. You’re not going to be calculating the slope, but instead, you’ll learn how to visualize it.
Level Change
Slope Change
Slope & Level Change