1. A probability estimate combiner comprising: a processing unit; a first input coupled to said processing unit; a second input coupled to said processing unit; and an output coupled to said processing unit; wherein said processing unit is adapted to execute a function C that has: a first property by which a quantity C(X, X) is further from a predetermined value X 0 than X, for all values of X in a predetermined domain of X not equal to X 0 and not equal to a set of bounds of the predetermined domain, wherein X 0 is an interior point in the predetermined domain that corresponds to equal probability that a result is true and false; a second property by which C(X, X 0 ) is equal to X; and a third property by which a quantity C(X 0 −ΔX, X 0 +ΔX) is equal to X 0 , where ΔX is an increment; wherein the processing unit outputs, at the output, a combined probability estimate that is obtained by evaluating the function C.