SAS for Mixed Models

Chapter 3: Mean Comparisons for Fixed Effects

3.1 Introduction. 49

3.2 Comparison of Two Treatments. 50

3.2.1 Example Using PROC TTEST. 50

3.2.2 Analysis Using PROC GLIMMIX.. 51

3.3 Comparison of Several Means: Analysis of Variance. 52

3.3.1 Relationship between LSMEANS and Fixed Effects Solution. 52

3.3.2 Standard Errors for Mean Comparisons. 54

3.3.3 Multiple Comparisons and Planned Comparisons. 57

3.4 Comparison of Quantitative Factors: Polynomial Regression. 58

3.4.1 Analysis of a Regression Experiment 58

3.4.2 Type I versus Type III Sums of Squares. 61

3.4.3 Direct Fit of Polynomial 62

3.4.4 Orthogonal Polynomial Contrasts. 65

3.5 Mean Comparisons in Factorial Designs. 67

3.5.1 Factorial: The Basics. 67

3.5.2 A More Complex Two-Way Factorial ...