Estimation of Genetic and Phenotypic Covariance Functions for Longitudinal Data
نویسنده
چکیده
Covariance functions are the ‘infinite-dimensional’ equivalents to covariance matrices for longitudinal data, i.e. many, ‘repeated’ records per individual taken over a period of time. Their properties are reviewed and illustrated with a numerical example. Restricted Maximum Likelihood estimation of genetic and phenotypic covariance functions fitting an animal model is described.
منابع مشابه
“dxmrr” - a Program to Estimate Covariance Functions for Longitudinal Data by Restricted Maximum Likelihood
OBJECTIVE Covariance functions (CF) are, in essence, the ‘infinite-dimensional’ equivalent to covariance matrices for traits measured repeatedly, potentially infinitely many times, along some continuous scale such as time or age. CFs produce a continuous description of the covariance structure over time, giving the covariance between any two ages as a function of the ages. DXMRR allows the esti...
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