23. The method of claim 22 wherein the resource transition probabilities define a probability that, within a session, a second resource will be referenced, after a first resource has been referenced.
23. The method of claim 22 wherein the resource transition probabilities define a probability that, within a session, a second resource will be referenced, after a first resource has been referenced. 25. The method of claim 23 wherein the probability is defined by: a) counting a number of times the second resource is referenced after the first resource has been referenced to generate a first count; b) adding the first count to a first constant to generate a first value; and c) counting a number of times the first resource has been referenced to generate a second count; d) adding the second count to a second constant to generate a second value; and e) dividing the first value by the second value.