Estimating genetic covariance functions assuming a parametric correlation structure for environmental effects [repeated records, random regression model] | [Estimation de la covariance génétique dans une structure de corrélation paramétrique pour les effets du milieu]
2001
Meyer, K. ((University of New England, Armidale (Australie). Animal Genetics and Breeding Unit))
A random regression model for the analysis of "repeated" records in animal breeding is described which combines a random regression approach for additive genetic and other random effects with the assumption of a parametric correlation structure for within animal covariances. Both stationary and non-stationary correlation models involving a small number of parameters are considered. Heterogeneity in within animal variances is modelled through polynomial variance functions. Estimation of parameters describing the dispersion structure of such model by restricted maximum likelihood via an "average information" algorithm is outlined. An application to mature weight records of beef cow is given, and results are contrasted to those from analyses fitting sets of random regression coefficients for permanent environmental effects
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