CHAPTER 11 - Other Linear Models

Abstract

This chapter introduces the concept of dummy or indicator variables that make an analysis of variance model look like a regression model. It discusses the use of dummy variables to analyze unbalanced factorial data sets and the use of models that contain both dummy and interval independent variables with emphasis on the analysis of covariance. It also discusses the use of covariance matrices to customize inferences on linear combinations of parameters and the use of weighted least squares when error terms show unequal variances. The chapter deals with linear models in which some parameters describe effects due to factor levels and others represent regression relationships. Such models include dummy variables representing factor levels as well as interval variables associated with regression analyses. The simplest of these models are illustrated that has parameters representing levels of a single factor and a regression coefficient for one independent interval variable. The analysis of models that include both measured and categorical independent factors are also presented.