1. A method for detecting fraudulent transactions between a customer and a vendor comprising: (a) receiving a plurality of transaction parameters from said vendor, said plurality of transaction parameters representing at least one transaction of at least one commodity between said customer and said vendor; (b) computing a first score as a function of said at least one commodity; (c) computing a second score as a function of a first one or more of said plurality of transaction parameters; (d) computing a fraud score based on said first and second scores; and (e) indicating to said vendor that said at least one transaction is fraudulent if said fraud score exceeds a first pre-determined threshold.