AN INTRODUCTION TO GENERALIZED LINEAR MIXED MODELS

Linear mixed models provide a powerful means of predicting breeding values. However, for many traits of economic importance the assumptions of linear responses, constant variance, and normality are questionable. Generalized linear mixed models provide a means of modeling these deviations from the usual linear mixed model. This paper will examine what constitutes a generalized linear mixed model, issues involved in constructing a generalized linear mixed model, and the modifications necessary to convert a linear mixed model program into a generalized linear mixed model program.