PS296 Lecture Notes - Lecture 20: Squared Deviations From The Mean
Document Summary
H0: mean language development scores are the same among all the children. Ha: at least one group mean among the children is different than another group mean. Single child mean: 9 twin: 6 triplet: 5. 8 9 = -1 squared = 1. 10 9 = 1 squared = 1. 7 5 = 2 squared = 4. 3 5 = - 2 squared = 4. 2 + 2 + 8 = 12 df = n k. Msbetween = sum of squared deviations (around grand mean) / df. Sum the squared deviations around the grand mean (remember to multiply them by n first) F = 13. 001 / 2 = 6. 501 (bigger than 4 = should be significant, f can never be negative) Our analysis of variance at alpha = . 05 testing whether single children, twins and triplets develop language at different speeds yielded a significant result, f (2, 6) = 6. 50, p < . 05.
