different arguments, prepositions, parts of speech, etc.).
we define an additional type level feature to be the ratio of the number of new domain n-grams (up to length three) that contain word w and which do not appear in the old domain to the total number of new domain n-grams containing w. With N w indicating the set of n-grams in the new domain which contain w, O w indicating the set of n-grams in the old domain which contain w, and |N w − O w | indicating the n-grams which contain w and appear in the new but not the old domain, we define Type:Contextas |Nw−Ow| |Nw| .