Complete Table 5.1 to find each Box effect by calculating the Box average €“ (Brand effect + grand mean). Crossed effects always sum to zero. Nested effects (Box) also sum to zero within each appropriate factor level (Brand). For example, Box 1, Box 2, and Box 3 effects sum to zero within the expensive Brand, and Box 1, Box 2, and Box 3 effects sum to zero within the generic Brand.
Table 5.1 Brand and Box effect calculations. Each Box effect is found by subtracting the Brand effect and grand mean from each Box average.

Box Brand Grand Box Brand Box Average Effect Mean Effect Exp 1 80 05 84 4.5 Exp 2 86 0.5 841.5 Exp Gen Gen Gen 84-4.5 86.5