Maximum Likelihood Estimation of Variance Components in Dairy Cattle Breeding Research

Abstract

A common problem in animal breeding research is estimation of variance and covariance components. Usual methods of estimation have been described by Henderson in 1953. In 1973 Henderson reported a computing algorithm for maximum likelihood estimation of variance components which may have been overlooked. This note reviews the Henderson computing technique and illustrates application of maximum likelihood estimation to 2 specific types of models for large, unbalanced data sets.