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arXiv · 2205.01281

A correlation structure for the analysis of Gaussian and non-Gaussian responses in crossover experimental designs with repeated measures

N. A. Cruz·O. O. Melo·C. A. Martinez
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Abstract

In this study, we propose a family of correlation structures for crossover designs with repeated measures for both, Gaussian and non-Gaussian responses using generalized estimating equations (GEE). The structure considers two matrices: one that models between-period correlation and another one that models within-period correlation. The overall correlation matrix, which is used to build the GEE, corresponds to the Kronecker between these matrices. A procedure to estimate the parameters of the correlation matrix is proposed, its statistical properties are studied and a comparison with standard models using a single correlation matrix is carried out. A simulation study showed a superior performance of the proposed structure in terms of the quasi-likelihood criterion, efficiency, and the capacity to explain complex correlation phenomena/patterns in longitudinal data from crossover designs

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N. A. Cruz, O. O. Melo, C. A. Martinez. 2022-05-03. A correlation structure for the analysis of Gaussian and non-Gaussian responses in crossover experimental designs with repeated measures. https://doi.org/10.1007/s00362-022-01391-z

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