Naive Bayes Classifier Results - Posterior Tab

Naive Bayes

Select the Posterior tab of the Naive Bayes Classifier Results dialog box to access options to generate a Posterior graph given your choice of independent variables. This is useful for observing the effect of adjusting an independent variable on the Posterior distributions (and, hence, predictions). This type of graph falls into a wider category known as Response graphs. Since the graph is two dimensional, all the independent variables must be fixed and one be selected as the x-axis variable with a specified range. Thus, while one specially chosen (see below) independent variable is altered (and plotted across the x-axis of the graph), values must also be provided for the other independent variables of the Naive Bayes Classifier. These are given fixed values, and are referred to as fixed independents (see below). Thus, the Posterior graph actually represents a one-dimensional slice through an N dimensional Posterior surface, where N is the number of independent variables.

Dependent variable

Naive Bayes supports multiple classification tasks. Use this drop-down list to select the categorical dependent variable for which you want to generate posterior distributions.

Independent variable

Select the independent variable that is to be varied across the x-axis.

Minimum range

Specify the minimum value of the independent variable on the x-axis. By default this is the smallest value of the variable within the original data set.

Maximum range

Specify the maximum value of the independent variable on the x-axis. By default this is the largest value of the variable within the original data set.

Fixed independents

To generate a Posterior graph, all the independent variables, except for the variable that is being altered across the x-axis, must be fixed to some value. Specify the values for these fixed independents by clicking the Fixed independents button to display a standard user input spreadsheet, which is used to enter values for each fixed independent variable.

Fixed independent list. This spreadsheet displays the values of the fixed independent variables.

Posterior spreadsheet

Click this button to generate the posterior spreadsheet of the class variables for the selected dependent variable (see Dependent variable above).

Posterior plot

Click this button to generate the graph of the posterior for the class variables of the selected dependent variable (see Dependent variable above).