330 Statistical Methods
Let’s apply this diagnostic to the mortality index data. The Regression com-
mand creates this plot for you, but it can be diffi cult to read because of its size.
We’ll move the plot to a chart sheet and reformat the axes for easier viewing.
To create a plot of the residuals versus the predictor variable:
1 Scroll to cell J1 in the Regression Statistics worksheet and click the
Temperature Residual Plot.
2 Click the Move Chart button located in the Location group of the
Design tab on the Chart Tools ribbon.
3 Click the As new sheet option button and then type Residuals vs.
Temperature and click OK.
4 Rescale the horizontal axes of the temperature variable, so that the
lower boundary is 30. The revised plot appears in Figure 8-16.
Figure 8-15
Residuals
showing a
curved
relationship
Figure 8-16
Residuals
versus
temperature
values