====== Determine Weights Of Evidence Continuous Occurrences ======

===== Description =====

This container determines Weights of Evidence coefficients for selected spatial variables with respect to a map of occurrences, using the same Weights of Evidence method as [[Determine Weights Of Evidence Coefficients]]. Unlike that container, which works from a transition between an initial and a final map, this one works from a map where each cell holds a count of how many times some event occurred at that location, so the map of occurrences does not need to be binary.

This container accepts one or more [[Name Map]] hooks nested inside it, each assigning a name to a map. These named maps supply the values for the spatial variables referenced by Ranges.

===== Inputs =====

^ Name  ^ Type  ^ Description  ^
| Occurrences  | [[Map Type]]  | Map of occurrences. Each cell holds the number of times the modeled event occurred at that location.  |
| Mask  | [[Map Type]]  | Map defining, through cells other than its null value, which cells should be analyzed. Its cells must be representable as a 32 Bit Integer.  |
| Ranges  | [[Weights Type]]  | Pre-defined ranges of each spatial variable for which the Weights of Evidence coefficients will be calculated. Only the ranges defined for the first transition are used; ranges defined for any other transition are ignored.  |

===== Optional Inputs =====

^ Name  ^ Type  ^ Description  ^ Default Value  ^
| Fix Abnormal Weights  | [[Boolean Value Type]]  | If true, recalculates weights that would otherwise result in abnormal values, such as those arising from a division by zero. If false, those abnormal values are assumed to be zero.  | No  |

===== Outputs =====

^ Name  ^ Type  ^ Description  ^
| Weights  | [[Weights Type]]  | Weights of Evidence coefficients obtained for the selected spatial variables, with respect to the given occurrences.  |

===== Group =====

[[Functor List#Calibration | Calibration]]

===== Notes =====

Cells with zero occurrences are also used in the calculation: one is always added to the number of occurrences found at a cell before it is used. Only cells located outside the area defined by Mask are excluded from the calculation.

Reports an error if a spatial variable named in Ranges is not provided by a nested Name Map hook.

Reports an error if Mask has cells that cannot be represented as a 32 Bit Integer.

This method was adapted from Agterberg & Bonham-Carter (1990), Goodacre et al. (1993), and Bonham-Carter (1994).

**References**

Agterberg, F.P. and Bonham-Carter, G.F., 1990: Deriving weights of evidence from geoscience contour maps for the prediction of discrete events. XXII Int. Symposium AP-COM, 381-395.

Bonham-Carter, G., 1994: Geographic information systems for geoscientists: modelling with GIS. Pergamon, 398 pp.

Goodacre, C. M., Bonham-Carter, G. F., Agterberg, F. P., Wright, D. F., 1993: A statistical analysis of spatial association of seismicity with drainage patterns and magnetic anomalies in western Quebec. Tectonophysics, 217, 205-305.

===== Internal Name =====

DetermineWeightsOfEvidenceContinuousOccurrences