Modeling and Multivariate Methods - SAS

142 Fitting Stepwise Regression Models Chapter 4
The Stepwise Report
3. Click Go.
The bottom figure in Figure 4.4 shows that all of the terms have been added, except RstPulse and
Weight.
Figure 4.4 Current Estimates Table for Forward Selection
after one step
after all steps
Backward Selection Example
In backward selection, terms are entered into the model and least significant terms are removed until all of
the remaining terms are significant.
1. Complete the steps in “Example Using Stepwise Regression” on page 135.
2. Click Enter All.
Figure 4.5 All Effects Entered Into the Model
3. For Direction, select Backward.
4. Click Step two times.
The first backward step removes RstPulse and the second backward step removes Weight.