A Coordinate-Free Approach of Estimation in Mixed Linear Models : Existence of the best linear unbiased estimators and of the best quadratic estimators in linear models

The existence conditions of both the best linear unbiased estimator of expected mean and the best quadratic unbiased estimators of covariance components in multivariate mixed linear models are presented in this book by using a coordinate-free approach. These conditions are extended to a family of multivariate growth curve models. The use of the coordinate-free approach of estimation offers an attractive computational form and allows to define certain finite dimensional Hilbert spaces corresponding to the considered models.