Review Variograms

To access this screen:

• Using the Advanced Estimation dialog, select the Review Variograms menu item.

To perform grade interpolation using kriging, an appropriate variogram model is needed. If co-kriging is used, a multivariate variogram model set is required which has the same ranges for all models.

Note: If you have imported data from Datamine Supervisor, variograms derived from the imported project are automatically associated with the corresponding estimation(s).

If zones are specified on the Select Samples screen, a variogram model set is required for each zone. If one of the non-kriging estimation methods has been selected (nearest neighbour, inverse distance and so on) then a variogram model is not required.

Variograms can be imported from a Datamine Supervisor project using the Import option on the Scenario Setup panel.

Usually the variogram models will have been fitted or imported at the Fit Models stage. However it is also possible to import or export a model on the Review Variograms screen.

Note: The Confirm Variograms panel allows the user to review the selected model or select a different model.

To add a new variogram model set:

1. Below the Available Variograms table (middle of the screen), click Add.

2. Define Model Parameters.

3. Define Variogram Model Set Properties.

To assign a variogram model to an estimation:

1. Review the Select an estimation to view or apply variogram models list.

   All estimations configured using the Define an Estimation screen are listed, together with the respective grade(s) and zone. For kriging estimates the default variogram model reference number is also shown.

2. Highlight one of the estimation runs (left-click).

3. Review the Available Variograms list and select an existing model.

   Available variogram model sets are displayed, along with the grades, zone, univariate or multivariate and how the fitting was performed - manually, automatically, or a "mix".

4. Click Apply variogram model to estimation [estimation number].

   Note: If only one variogram model is available, it is automatically assigned to the highlighted estimation and the application button is unavailable.

To manage the Available Variograms list:

• Click Add to insert a new variogram model with default parameters into the list.

• Click Remove to remove an existing variogram from the current set.

• Click Clear list to remove all variograms from the scenario.

• Click Import to import a variogram model file and show it in the table above.

  Note: During variogram model import, file contents will be analyzed to ensure it contains the fields required to complete the estimation process. For example, if a zone field (either the first or second zone) is expected but cannot be found in the incoming file, a message will be displayed explaining which field is expected and cannot be found. Similarly, other required fields such as VSETNUM, GRADE, GRADE2 and TRANS fields are checked.

• Click Export to export the currently selected variogram to an external file, for import in other projects.