## Exact tests in simple growth curve models and one-way ANOVA with equicorrelation error structure.(English)Zbl 1014.62067

Summary: We consider exact tests with several equicorrelation error structures and combination of equicorrelation covariance structures in simple growth curve models having single or multiple treatments and in one-way ANOVA models. Exact inferences using generalized $$p$$-values are obtained. Tests for equal treatment effects under equal equicorrelation error terms and for unequal equicorrelation error terms are also developed. Two examples are given to illustrate the importance of our results. According to our findings, we would be better off dropping the assumption of equal variance when the heteroscedasticity is serious. Therefore, tests based on generalized $$p$$-values without the assumption of equal variance are much more powerful than tests with this assumption.

### MSC:

 62H15 Hypothesis testing in multivariate analysis 62J10 Analysis of variance and covariance (ANOVA) 62F03 Parametric hypothesis testing
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### References:

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