Tuesday, November 13 Analysis of Variance
Between-group variance estimate F = within-group variance estimate _ SST = (X - X)2 SSB = NG (XG - X)2 SSW = (X1 - X1)2 + (X2 - X2)2 + •••• (Xk - Xk)2 SST = SSB + SSW _ _ _ _ _
Between-group variance estimate F = within-group variance estimate MSB = SSB / dfB MSW = SSW / dfW where dfB = k-1 (k = number of groups) dfW = N - k
Protected t-test t = Xi - Xj MSW ( 1/Ni + 1/Nj) _ Where df = N - k
dfB (F - 1) = dfB F + dfW Epison bears the same relationship to F that rpb bears to t.