Generalization
Fig. 4 suggests that the gradient of generalization differed between the groups, with a nearly flat gradient on the first test
trial in group BETWEEN and a sharper gradient in group WITHIN. Over the course of extinction, a gradient also emerged in
group BETWEEN. In order to analyze these impressions from the graphs,weconducted separate ANOVA’s for groupBETWEEN
and group WITHIN (because of the inherent difficulty of directly comparing a between- and within-groups design within
one statistical analysis).