Most of the statistical techniques used to evaluate the data obtained from toxicity studies are based on the assumption that the data show a normal distribution and homogeneity of variance. Literature review on toxicity studies on laboratory animals reveals that in most of the cases homogeneity of variance alone is examined for the data obtained from these studies. But the data that show homoge...

In this article, we propose a parametric bootstrap (PB) test for testing main, simple and interaction effects in heteroscedastic two-way MANOVA models under multivariate normality. The PB test is shown to be invariant under permutation-transformations, and affinetransformations, respectively.Moreover, the PB test is independent of the choice ofweights used to define the parameters uniquely. The...

Cross-species studies using microarray gene expressions help discover genetic diversity among different species, the results of which are fundamental to comparative genomics. Various approaches have been used for cross-species studies, such as homogeneity test and cluster analysis. A homogeneity test provides a homogeneity significance ranking for each gene pair whilst cluster analysis looks at...

Testing for homogeneity in finite mixture models has been investigated by many authors. The asymptotic null distribution of the likelihood ratio test (LRT) is very complex and difficult to use in practice. In this paper we propose a modified LRT for homogeneity in finite mixture models with a general parametric kernel distribution family. The modified LRT has a χ2-type null limiting distributio...

Nonparametric order tests for homogeneity and component independence are proposed, which are based on data compressors. For homogeneity testing the idea is to compress the word obtained by ordering the combined samples and writing the number of the sample in place of each element. H0 should be rejected if the string is compressed to a certain degree and accepted otherwise. We show that such a t...

• A marginal homogeneity model tests whether the row and column distributions of a square contingency table have the same sample margins. However, for variables with ordered categories, the marginal homogeneity model does not take into account the ordering information, leading to significant loss of power. Score-based tests have been proposed for ordinal variables. In this paper, we extend the ...

Detecting and locating changes in highly multivariate data is a major concern in several current statistical applications. In this context, the first contribution of the paper is a novel non-parametric two-sample homogeneity test for multivariate data based on the well-known Wilcoxon rank statistic. The proposed two-sample homogeneity test statistic can be extended to deal with ordinal or censo...

We propose a test for testing the equality of several high-dimensional covariance matrices stationary processes with general distribution. The asymptotic distribution proposed is proved to be χ2 Both numerical simulation and empirical study illustrate that has perfect performance, in particular, its power can approach 1 on set three known distributions.