1. A method for processing events, the method comprising the steps of: a computer receiving a plurality of input events, each input event comprising one or more factors; the computer processing each of the plurality of input events based on at least a first event processing rule wherein the at least first processing rule causes the computer to evaluate the one or more factors, and based on a result of the evaluation, assigning each of the plurality of input events a Boolean output value; the computer generating an output event containing the one or more factors and the Boolean output value; and the computer generating a pair of additional event processing rules based on output events for which the at least first event processing rule caused the output events to have a false-negative or false-positive Boolean output value, the additional rules to be included in the at least first event processing rule, wherein one of the pair of rules is derived by the computer from output events having a false-negative Boolean output value and the other of the pair of rules is derived by the computer from output events having a false-positive Boolean output value.