13. The method according to claim 12 , further comprising: identifying those of the categories of the words that are associated with multiple topics; and removing at least some of the words associated with at least one of the identified categories from the collections prior to inferring the topics.
12. The method according to claim 11 , further comprising: maintaining in a database a plurality of documents regarding the vertices and the edges, each of the documents associated with one or more of the vertices; creating the graph based on the data; inferring from the documents the topics associated with each of the vertices and proportions of the words in the collection associated with that vertex that are associated with each of the topics; inferring from the documents proportions of the words associated with each of the topics among all of the vertices; sampling each of the words from a multinomial probability distribution using the proportion of the words associated with each of the topics; calculating a joint distribution for the collection of the words for each of the vertices based on the multinomial distribution for the words for that vertex; and using the joint distribution to identify the one or more of the anomalous types of words for each of the communities.