Advanced Estimation - Parameters

To access this dialog:

Using the Advanced Estimation dialog, select the Import Parameters menu item.

This panel is part of the Advanced Estimation dialog and is used to export or import predefined parameter files from and into your estimation workflow.

Exporting Parameters

Export mode is enabled by selecting the Export radio button.

You can export your existing advanced estimation parameters using the fields provided; either specify or locate a folder to store your output file for each category.

If the Use Default check box is selected, files will be exported to the current project directory using the default file names for each data category. Disabling this check box allows you to set custom file names and locations for each item.

A default name is comprised of the currently-specific Output model name (Select Prototype panel) and a standard suffix.

If the Angled Estimation check box is selected, the angular estimation parameters defined on the Estimate Angles panel will be included in the export.

The Export button will remain disabled until at least one of the exportable table is available.

Importing Parameters

Import mode is enabled by selecting the Import radio button.

Import Parameters can also be used for importing ESTIMA format parameter files.

Once a sample file and prototype model have been defined, you can import parameter files that relate to these two items. When files are imported, it is assumed that a model and samples are already defined. Validation checks will be performed to ensure the fields represented by the imported table data are relevant to the model and samples, particularly with regards to zone and grade variable specification.

You can import any combination of estimation parameter files using the Parameters panel. For example, if required, you can just import a variogram model file.

More information on these files can be found in the COKRIG process help file.

If mismatches are found, you will be alerted to this via the Output control bar. You will need to resolve these before proceeding as issues in imported data can prevent an estimation from being run, or produce incorrect/unexpected results.

All estimation parameter files must be specified on this form for import to take place, including:

An estimation parameter file. If angular estimation parameters are contained, the Estimate Angles panel will be automatically updated with imported information. If there are more than one angular estimation records in the file, then the first estimation record is used as reference and the input variables from any subsequent estimation records (which matches the reference estimation) are added to it.

The parameter file can have records for both angular and grade interpolation. For grade interpolation, the variable fields are the input grades which are matched against the sample data. If the grade does not match, an error message is displayed during estimation file import.

The information about applies to importing both COKRIG and ESTIMA style parameter files.
A field list table containing field names. This is aa file that contains field names of input variables to be used for estimation (which must be present in the input samples file) and output variables to be included in the file specified by output grade model.
A variogram model: if multivariate estimation runs have been defined, this file must contain the columns GRADE and GRADE2.
Search parameters: this must contain the following 12 mandatory fields:

SREFNUM which is used to store a reference number for each record which is then specified by the SREFNUM parameter in COKRIG.
SDIST1, SDIST2, SDIST3 specifying the search distances in the X, Y and Z directions respectively.
SAXIS1, SAXIS2, SAXIS3 specifying the first, second and third axes which the search volume is to be rotated around (1 = x, 2 = Y, 3 = Z).
SANGLE1, SANGLE2, SANGLE3 which specify the clockwise angles which search volume is rotated around the axes specified by SAXIS1, SAXIS2, AXIS3.
MINNUM1 which is the minimum number of samples required per estimate
MAXNUM1 which is the optimum number of samples to be used per estimate.

Custom zones parameters: this must be specified if soft zones are to be used. It contains the following fields:

ZREFNUM (numeric) - the soft zone reference number.
ZONE1: (numeric or alphanumeric; same as ZONE1_F) this contains values of ZONE1_F, the first field used for zone selection.
ZONE2: only included if ZONE2_F has been specified (numeric or alphanumeric; same as ZONE2_F) this contains values of ZONE2_F, the second field used for zone selection.
DESCRIPTION: Description of soft zone ZREFNUM.
COUNTFLD: Name of the optional field created in output model indicating the number of samples from ZONE1 and/or ZONE2 THAT were used in estimation.

Convert normalized variogram to true variance of the sill

Variogram models (Variograms) structures can be represented with the true variance or variances normalized to the sill (or sample variance). Variograms with the true variance display the nugget (C0) and each structure (C1, C2..) as variances that when summed equal to the variance of the samples. This variogram might look like this:

In this example of a variogram with the true variance, the sill value is 2.11 (Calculated from C0 + C1 + C2 or 0.21 + 0.89 + 1.01).

Variograms could also be normalised to the variance of the sill. This means that all structure variances are divided by the true sill value (C0+C1+C2..). For these variograms, the sum of the nugget (C0) and each structure equal 1. This is done so variograms are easier to compare to each other. This variogram might look like this:

In this example of a normalized variogram, the sill value is 1.00 (Calculated from C0 + C1 + C2 or 0.10 + 0.42 + 0.48)

When converting a variogram model to have true variance, the sample variance is assumed as the true variance for the sill value.

The results from a kriging process like COKRIG or ESTIMA are the not affected by the type of model. However non-linear processes, like Uniform Conditioning, require a variogram model to have the true variance. Both types of variogram are correct, and is just a different choice of convention.

Datamine Supervisor saves variograms as normalized by default (this setting can be changed in any Supervisor project), however Advanced Estimation Variography displays variograms using the true variance. To display Supervisor variograms in Advanced Estimation, there is a tool to automatically convert a normalized variogram to a variogram with the true variance of the sill.

In order to convert a variogram, the sample file and zones need to be selected on the Select Samples panel. You have the option to convert normalized variograms when importing using the Fit Models or this Import Parameters panel.

Clear: clear the current panel details.

Import: import the files listed above.

Export: export the files listed above.

	Related Topics
	Advanced Estimation Introduction Grade Estimation Parameter File The COKRIG Process