Modeling and Multivariate Methods - SAS

Chapter 9 Performing Nonlinear Regression 255
Nonlinear Fitting with Fit Curve
Figure 9.8 Parameter Comparison
The Analysis of Means red triangle menu has the following options:
Set Alpha Level
Sets the alpha level for the test.
Show Summary Report Shows or hides a report containing the parameter estimates, the decision limits,
and whether the parameter exceeded the limits.
Display Options Contains options for showing or hiding decision limits, shading, and the center line.
Also contains options for changing the appearance of the points.
For more information on the Analysis of Means report, see the Basic Analysis and Graphing book.
Equivalence Test
The Equivalence Test report gives an analysis for testing the equivalence of models across levels of the
grouping variable. See Figure 9.9. After selecting the option, you specify the level of the grouping variable
that you want to test against every other level. There is a report for every level versus the chosen level.
The equality of the parameters is tested by analyzing the ratio of the parameters. The default decision lines
are placed at ratio values of 0.8 and 1.25, representing a 25% difference.
If all of the confidence intervals are inside the decision lines, then the two groups are practically equal. If a
single interval falls outside the lines (as shown in Figure 9.9), then you cannot conclude that the groups are
equal.