For each of the following, sketch hypothetical graphs in the singlesubject style that illustrate each of the alternative outcomes.

1. Multiple baseline across three settings:

a. The treatment program works.

b. One cannot discount a history or maturation effect.

2. A–B–A–B design

a. The treatment program works.

b. It is hard to tell if the program brought about the change or if another factor such as maturation was responsible.