4. The system according to claim 1 , wherein the at least one processor is further configured to: calculate a likelihood of that community being associated with the words of all of the categories in the collections associated with the vertices in that community; for each of the word categories associated with that community, calculate a modified score comprising a likelihood of that community being associated with the collections associated with the vertices in that community when those collections exclude the words of that category; subtract the score from the modified score and comparing a result of the subtraction to a threshold; compare the result of the subtraction to a threshold for each of the word types; and set those of the word types where the result exceeds the threshold as the word types to be removed.
4. The system according to claim 1 , wherein the at least one processor is further configured to: calculate a likelihood of that community being associated with the words of all of the categories in the collections associated with the vertices in that community; for each of the word categories associated with that community, calculate a modified score comprising a likelihood of that community being associated with the collections associated with the vertices in that community when those collections exclude the words of that category; subtract the score from the modified score and comparing a result of the subtraction to a threshold; compare the result of the subtraction to a threshold for each of the word types; and set those of the word types where the result exceeds the threshold as the word types to be removed. 5. The system according to claim 4 , wherein each of the edges is associated with a portion of the words in the collection associated with the vertex and wherein the at least one processor is further configured to: divide the words for each of the communities into a set of the words that are associated with edges between the vertices of that community and a set of the words associated with the edges that are between one of the vertices of the community and one of the vertex outside of that community; and use the sets of the words to calculate the score and the modified score.