Hi @ArnieWaddell1
The graph is showing the distribution each field in the cross validation Table (change the field with the Field pulldown) using a kernel density estimation. Think of it like a smoothed histogram of the Measured values, Predicted values, or Errors.
Overlaying the Measured and Predicted fields is the most important use of the Distribution tab. This lets you compare the distribution of true values and the cross validated predictions. Ideally, the two should have very similar distributions, and big deviations might indicate problems in the interpolation model.
-Eric