Analysis of familial data: Linear-model approach

A linear-model approach is proposed for deriving the maximum likelihood estimates of the mother–sib interclass correlation and other parameters from familial data when the families have unequal numbers of offspring. It leads to an algorithm which involves the maximization of an explicit function of a variable for estimating one parameter and direct substitutions for other parameters. The algorithm is believed to be much simpler and more practical than that proposed by Rosner (1979). Some other advantages of the linear-model approach are also discussed.