78. A method of selecting advertisements in a computer including a data storage, comprising: providing a database of electronic advertisements; converting an observed behavior of a user computing device in the computer to a behavior vector; comparing the behavior vector to a plurality of entity vectors, the entity vectors indicative of the electronic advertisements, so as to identify at least one entity vector closely associated with the observed behavior; accessing the electronic database with the identified entity vector, and selecting at least one electronic advertisement to communicate to the user computing device.
79. The method as defined in claim 78, wherein the selecting includes selecting an electronic advertisement that is under-selected according to a selection schedule and inhibiting the selection of an electronic advertisement that is over-selected according to the selection schedule.