Associate Responses With Point Theme...

This function allows you to determine the final probabilities at the locations of the training points you input to the weights of evidence model. Or, at some other set of points in the study area. This function creates a table that contains information about the locations of a set of points and the probabilities calculated at those points.

When you select this item from the Weights of Evidence menu, a dialog appears, prompting you to select a point theme and a response theme.

Arc-WofE first appends a new field, RecordID, to your point theme's attribute table and writes the number of each record to that field. This ensures that each point has a unique identifier. A new .dbf file is created with one record for each point. In each record, the unique record number, as well as the x and y coordinates for each point, are written.

Arc-WofE then determines in which unique condition (record) in the response theme each point is located and copies the posterior probability, posterior logit, sum of weights, etc. from the response theme's attribute table to the new table. The final .dbf table contains in one place, the location of each of the points and the responses measured at those locations.

How can I symbolize or display the probability information at each point

You can either join the new table to your point theme using the RecordID in both tables as the 'to' and 'from' join fields, or you can add the new table to a View document as an X,Y event theme.

To join the associated .dbf table to your point theme:

Open the new table, Pntresp<#>.dbf, and select the field 'RecordID'.

Open the point theme attribute table and select the field 'RecordID'.

With the point theme attribute table active, click the 'Join' button, or select Join from the Table menu in the Table document interface.

Now, if you double click on the point theme's legend to edit it, the fields in the joined table are available for symbolization.

Arc-View on-line Help Topic: joining tables

To create an XY event theme

In a View document, from the View menu, select 'Add Event Theme...'.

In the dialog box that displays, select the table, the X field and the Y field, and click 'OK'.

Arc-View on-line Help Topic: themes, adding