@brghtwk The main idea behind the tool is to investigate the impact of slightly changing the semivariogram parameters of an existing model (often called a "sensitivity analysis"). Since you must choose specific values for semivariogram parameters, it is reassuring if you get nearly the same results by using slightly different semivariogram parameters. If the predictions change a lot for small changes of the semivariogram parameters, then your results may only reflect the arbitrary parameter choices, rather than an accurate representation of the underlying process.
The tool tests this by adding random noise to the semivariogram parameters (range, nugget, sill, etc) and recomputing predictions. You must provide the initial model (a geostatistical layer) using the Geostatistical Wizard. You'll define the semivariogram model (Spherical, Exponential, etc) along with initial parameter values. The Semivariogram Sensitivity tool then adds the noise to the parameters.
