# Nonlinear Estimation Results - Residuals Tab

Purpose of Nonlinear Estimation

Select the Residuals tab of the Nonlinear Estimation Results dialog box to access the options described here.

Observed, predicted, residual values. Click this button to create a spreadsheet containing the observed values, predicted values, and residual values (i.e., observed values minus predicted values).

Normal probability plot of residuals. Click this button to produce a normal probability plot, which provides a quick way to visually inspect to what extent the pattern of residuals follows a normal distribution. If the residuals are not normally distributed, they will deviate from the line. Outliers can also become evident in this plot. If there is a general lack of fit, and the data seem to form a clear pattern (e.g., an S shape) around the line, the dependent variable may have to be transformed in some way (e.g., a log transformation to "pull in" the tail of the distribution, etc.).

Classification of cases & odds ratio. Click this button to produce a spreadsheet containing the classification of cases and odds ratio.

Save predicted and residual values. Click this button to display predicted and residual scores (as well as all variables in the current data file) in a standard STATISTICA spreadsheet (shown in an individual window, regardless of the settings on the Options dialog box - Output Manager tab or in the Analysis/Graph Output Manager dialog box). You can, however, add the spreadsheet to a workbook or report using the or buttons, respectively. Note that in order to save the spreadsheet, you must select the spreadsheet and select Save or Save As from the File menu.

Histogram of residuals. Click this button to create a plot of the frequency distribution (Histogram) of the residuals, overlaid with the normal curve (the expected frequencies for the normal distribution).

Half-normal probability plot. Click this button to create a half-normal probability plot, which is constructed in the same way as the standard normal probability plot, except that only the positive half of the normal curve is considered. Consequently, only positive normal values will be plotted on the Y axis.

Predicted vs. observed values. Click this button to produce a plot of the predicted values vs. the observed values.

Predicted vs. residual values. Click this button to create a plot of the predicted values vs. the residual values.