Areal weights with Thiessen polygons
In the Thiessen method station weights are determined in proportion to their representative areas defined by a polygon. The polygons are formed from bisectors of the station interconnections around the stations and/or the catchment boundary. Let the area of the polygon around station X~i~ be denoted by A~i~ and let the total catchment area be A~c~ , then the station weight is: A~i~ /A~c~ . The sum of station weights do necessarily add up to 1.
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