Kriging Cross Validation Approaches

Discussion created by perstabo on May 9, 2012
Latest reply on May 21, 2012 by slynch-esristaff

I perform ordinary kriging (or co-kriging) on a dataset and in the final cross validation step of the geostatistical wizard, I can see a table which shows actual vs predicted values for each point in the dataset.

When I finish the geostatistical wizard, I create a prediction surface which is added as a layer to my project. I can then right click on the prediction layer and select the "Validation/Prediction" option which opens up the "GA Layer to Points" tool. I select the input dataset and the field which I had originally performed kriging on. This creates a new shape file which I can add to my project.

When I examine the attribute table for the new layer that I have just created using the "Validation/Prediction" option, it also shows actual and predicted values for each point in the data set. However, the predicted values are substantially different from those that were shown in the final cross validation screen of the geostatistical wizard.

Can anyone tell me why they are different, and which cross validation table is correct? I don't understand :-(

Many thanks for all your help

Stephen Vitoria