1. A computerized system for authenticating an electronic transaction, the system comprising: a digital storage assembly storing data characteristics for a purported authorized user of an electronic system based on a plurality of measured interactions with one or more input devices of the electronic system, a user probability distribution representation for an authorized user based on a plurality of measured interactions with an input device, a global probability distribution representation for a wide population based on a plurality of measured interactions with an input device; and a processing assembly configured to execute computer-readable instructions including determining a value indicative of whether the purported authorized user is the authorized user, utilizing (a) the data characteristics of the purported authorized user, (b) the probability distribution representation for the authorized user, and (c) the probability distribution representation for the wide population, and associating the purported authorized user to the authorized user for authenticating an electronic transaction attributable to the authorized user, if the value is above a prescribed threshold.