Residual Analysis

Using the transformed data and residuals that you saved to the active dataset allows you to create a scatterplot of the predicted values by the transformed values of Package design.

To obtain such a scatterplot, recall the Chart Builder and click Reset to clear your previous selections and restore the default options.

Figure 1. Chart Builder
Chart Builder
  1. In the Chart Builder, select the Scatter/Dot gallery and choose Simple Scatter.
  2. Select Residual as the y-axis variable.
  3. Select Package design Quantification as the x-axis variable.
  4. Click OK.
Figure 2. Residuals for Categorical Regression
Residuals for categorical regression

The scatterplot shows the standardized residuals plotted against the optimal scores for Package design. All of the residuals are within two standard deviations of 0. A random scatter of points replaces the U-shape present in the scatterplot from the standard linear regression. Predictive abilities are improved by optimally quantifying the categories.