14.5 In a study of the development of the concepts of conservation of quantity and weight, two standardized and quantifiable tasks (T, 2 levels) are presented to each of 72 children. Mastering the first task requires that a child grasp the notion of conservation of quantity whereas the second task depends on conservation of weight. The score is the number of trials required for the mastery of the task. Both age (A, 3 levels: 5, 7, and 9 years) and sex (X, 2 levels) are included as major variables in the design.

(a) Present the sources of variance associated with the design of this study as well as the df and EMS (using numbers where possible).

(b) State the error term and its df for tests of the following simple effects: (i) The effect of age for the conservation-of-quantity task (T1); (ii) the effect of age for all male subjects on the T1 task; and (iii) the effects of task on the scores of all male subjects.