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| If ind equals 1 then we reject nonequivalence concluding $$\theta^text{2} < d for given $$eta^text{2}$$, group sizes and type II error. | If ind equals 1 then we reject nonequivalence concluding $$\theta^text{2}$$ < d for given $$eta^text{2}$$, group sizes and type II error. |
R code for equivalence test in one-way ANOVA
For an effect size in an one-way anova $$\theta^text{2}$$:
$$\thetatext(2)$$ = $$\frac{ etatext{2} (N-k)}{(1-eta^text{2}) \bar{N}}$$
we can formulate hypotheses of form
H0: $$\thetatext{2}$$ ≥ d and HA : $$\thetatext{2}$$ < d .
If ind equals 1 then we reject nonequivalence concluding $$\thetatext{2}$$ < d for given $$etatext{2}$$, group sizes and type II error.
[TYPE INTO R THE DESIRED INPUTS RSQ, N, K, DCRIT AND BETA USING VALUES IN FORM BELOW].
RSQ represents partial $$eta^text{2}$$ using one of Cohen's [:FAQ/effectSize:rules of thumb], n is a vector of group sizes, dcrit represents the [:FAQ/mageq:criterion for d] and beta is the type II error.
rsq <- 0.006 n <- c(10,12,13,15) dcrit <- 0.5 beta <- 0.05
[THEN COPY AND PASTE THE BELOW INTO R]
k <- length(n) ns <- sum(n) psi2 <- (rsq/(1-rsq))*k*((ns-k)/ns) cstats <- (k*(k-1)/ns)*qf(beta,k-1,ns-k,(ns/k)*dcrit*dcrit) ind <- 0 if (psi2 < cstats) ind = 1 print(ind)
