1. A computer-implemented method for automated classification of events, said method comprising: receiving, at said entity, at least one event, wherein said event comprises on-line activity between said user and said entity; determining a plurality of event units from said event; retrieving a plurality of keywords from a keyword database, each retrieved keyword matching a corresponding event unit; identifying a category associated with each of said keywords retrieved; storing a set of statistical parameters, based on past analysis of events, for each keyword and said category associated with each of said keywords retrieved, wherein said statistical parameters comprise ambiguity parameter values of said keywords and statistical probabilities that said keywords and said categories dominate one or more other of said keywords and said categories; selecting a dominant keyword from said keywords retrieved based on said statistical parameters by: using said at least one keyword category and an ambiguity parameter value calculated for said each keyword as a factor of a conditional probability that said at least one keyword category is associated with said dominant keyword; and categorizing said event based on said category associated with said dominant keyword, wherein said category identifies primary subject matter for said event.