= Magnitude of effect size, t =

Taken from Wellek (2003) Table 1.1(v) and page 164

||||||||||||<20% style="VERTICAL-ALIGN: top; TEXT-ALIGN: center">Setting ||Parameter ||Reference Value ||Strict t ||Liberal t ||
||||||||||||<20% style="VERTICAL-ALIGN: top; TEXT-ALIGN: center"> Sign Test || P(difference>0) ||1/2 || 0.10 || 0.20 ||
||||||||||||<20% style="VERTICAL-ALIGN: top; TEXT-ALIGN: center"> Mann Whitney || P[X>Y] ||1/2 || 0.10 || 0.20 ||
||||||||||||<20% style="VERTICAL-ALIGN: top; TEXT-ALIGN: center"> 2 Binomials || Log $$\frac{p_text{1}(1-p_text{2})}{(1-p_text{1})p_text{2}} || 0 || 0.41 || 0.85 ||
||||||||||||<20% style="VERTICAL-ALIGN: top; TEXT-ALIGN: center"> Paired t || $$\frac{\mbox{Paired difference}}{\mbox{sd(difference)}}$$ || 0 || 0.25 || 0.50 ||
||||||||||||<20% style="VERTICAL-ALIGN: top; TEXT-ALIGN: center"> Unpaired t || $$\frac{\mbox{Group mean diff}}{\mbox{average group sd}}$$ || 0 || 0.36 || 0.74 ||
||||||||||||<20% style="VERTICAL-ALIGN: top; TEXT-ALIGN: center"> One-way ANOVA || [eta^2 ^ (N-k)][(1-eta^2 ^) mean(N)] || 0 || 0.25 || 0.50 ||

where mean(N) is the average group size