1. A device for determining whether to apply an input to at least one of two decision systems, the device comprising: a) a relevance determination unit for determining a relevance of the input with respect to each of the at least one of the two decision systems; b) means for applying a predetermined relevance parameter to each of the determined relevance associated with each of the at least one of the two decision systems; and c) means for applying the input to the at the least one of the two decision systems if the relevance associated with that decision system meets the predetermined relevance parameter.