PSY202H1 Study Guide - Pooled Variance, Analysis Of Variance, Effect Size
Document Summary
Mean square (anova d) check critical value (df = df between txts. Ss = x 2 ( x )2. Each txt has own ss (sum of squared deviations) Ssbetween = sstotal sswithin (if varying sample size, use: . N ) df total wit h df . = (n-1) each n is subtracted by 1 & then summed(n-k) or dftotal -dfbtwn df between = k-1 between/wit h . Pooled variance = mswithin(avg of all the diff"t sample variances) Sample variance contributes directly to mswithin value. Msbetween denom[within]) find critical region ** if in critical region, unlike (p < 0. 05) we could obtain a value this large if h 0 was true, therefore reject h 0 conclude sig. effect** How lge the effect is aka how much of the variability in scores is accounted for by the diffs btwn txts: the numer of the f-ratio (msbetween) measures how much difference (variance) exists between the txt means.
