Formulas for estimating ω2 are based on the assumption that sample sizes, nj, are proportional to the sizes of their respective treatment populations. Because this assumption is frequently violated, a general method of estimating ω2 for the one-factor, fixed-effects design is presented. Given the relative sizes of the treatment populations, unbiased estimators are obtained for the population grand mean, μ, for individual treatment effects, αj, and for the numerator and denominator of ω2.
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