Linear Model in SAS (2.1) - the Design Matrix Is of Less Than Full Rank !

There are three ways to find a solution for linear model parameters when the design matrix is of less than full rank. 这篇是Linear Model in SAS (2)中Estimable Functions的先决知识点.本文为辅助材料,整理自JH的讲义。

Introduction

其中第2点也是如下博文采用的方法:

Linear Model in SAS (2) - Hypothesis Testing and Estimable Functions

Reducing the Model to One of Full Rank

Example: (One-way ANOVA with 2 groups)

Finding a Generalized Inverse \((X'X)^-\)

Theorem

Example: (One-way ANOVA with 2 groups, continued)

We have

Imposing Identifiability Constraints

Theorem

Example: (One-way ANOVA with 2 groups, cont.)

Set \(\alpha_1+\alpha_2=0\), i.e.

Reference


An overview of the topic for this course

Chapter 1: Introduction

Chapter 2: Review of linear algebra and matrices

Chapter 3: Random vectors

Chapter 4: The multivariate normal distribution and distributions of quadratic forms

Chapter 5: Least squares estimation

Chapter 6: Properties of least squares estimates

Chapter 7: Design matrices of less than full rank

Chapter 8: Orthogonal structure in the design matrix

Chapter 9: Generalized least squares

Chapter 10: Estimable functions

Chapter 11: Hypothesis testing