“…This state would be followed by a second transition leading to mastery of both skills. Bergan and his colleagues developed models that reflect this possibility (Bergan, 1983; Bergan, Stone, & Feld, 1984). In the case of two hierarchically ordered skills, these models include five latent classes: a nonmastery class, a transition class involving inconsistent performance on the subordinate task accompanied by nonmastery of the superordinate task, a class involving mastery of the subordinate task and nonmastery of the superordinate task, a second transition class characterized by mastery of the subordinate task and inconsistent performance on the superordinate task, and finally a class involving mastery of both tasks.…”