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arXiv · 2410.04700

Nonparametric tests for interaction in two-way ANOVA with balanced replications

Bao Khue Tran·Amy S. Wagaman·Andrew Nguyen·David Jacobson·Bradley Hartlaub
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Abstract

Nonparametric procedures are more powerful for detecting interaction in two-way ANOVA when the data are non-normal. In this paper, we compute null critical values for the aligned rank-based tests (APCSSA/APCSSM) where the levels of the factors are between 2 and 6. We compare the performance of these new procedures with the ANOVA F-test for interaction, the adjusted rank transform test (ART), Conover's rank transform procedure (RT), and a rank-based ANOVA test (raov) using Monte Carlo simulations. The new procedures APCSSA/APCSSM are comparable with existing competitors in all settings. Even though there is no single dominant test in detecting interaction effects for non-normal data, nonparametric procedure APCSSM is the most highly recommended procedure for Cauchy errors settings.

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Bao Khue Tran, Amy S. Wagaman, Andrew Nguyen, David Jacobson, Bradley Hartlaub. 2024-10-07. Nonparametric tests for interaction in two-way ANOVA with balanced replications. https://arxiv.org/abs/2410.04700

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