Jill went to Harry's Hair Salon to get a permanent wave; the lotion Harry applied to Jill's hair burned her scalp. The test to determine whether the common law or Article 2 applies here is the test.

Using mr smith and his id, identify two potential internal validity threats that might affect the a—b design. tell me how that threat might impact conclusions in the a—b design. note #1: you cannot use maturation (since i already did that one for note #2: there are some mr smith id threats that won’t have much impact in a single case design.