Determine Weights Of Evidence Correlation

Description

This container calculates the correlation between a pair of maps.

Inputs

Name	Type	Description
Ranges	Weights	Pre-defined intervals for continuous gray-tone variable.
Transition	Transition Set	A specified transition.

Optional Inputs

Outputs

Name	Type	Description
Report	Table	Table containing a full report of correlation calculation. These are essentially the same results showed in the message log, but in a table format.

Group

Calibration

Notes

When considering the advantages of Weights of Evidence over other statistical methods, such as Logist or Linear Regression, one can mention that it is not constrained by the classical assumptions of parametric methods, which spatial data often violate. Furthermore, the effect of each spatial variable can be calculated independently of a combined solution. The only assumption that must be made is that the predictive maps are spatially independent, which can be tested using pairwise tests for categorical maps, such as the Cramers Coefficient, Contingency Coefficient, and the Joint Information Uncertainty (Bonham-Carter, 1994). As a result of these tests, one of the correlated variables can be either eliminated or combined with the second to form a new variable that will replace both in the integrated model. The two former methods are based on the chi-square statistic while the latter is derived from the Joint Entropy measure; all methods are calculated from a contingency table produced by cross-tabulating pair of maps.

References

Bonham-Carter, G 1994. Geographic information systems for geoscientists: modelling with GIS. New York, Pergamon.

Internal Name

DetermineWeightsOfEvidenceCorrelation

Usage examples

See practical examples of this functor in Lesson 18: Building a land-use and land-cover change simulation model