5. The computer-executed method of claim 4 , wherein determining one of the affinity scores comprises calculating a weighted sum over the users in the intersecting population.
5. The computer-executed method of claim 4 , wherein determining one of the affinity scores comprises calculating a weighted sum over the users in the intersecting population. 6. The computer-executed method of claim 5 , wherein a weight is assigned to each user in the intersecting population, and wherein each of the weights is determined based on at least one from the group consisting of: a number of times the user has authored one of the content items associated with one of the mappings, and a probability that the user will author a content item relevant to either the event or topic associated with one of the populations forming the intersecting population.