Given a noun phrase, the segmentation problem is thus choosing a segmentation that maximizes the following conditional probability: Complementary to the segmentation problem is the semantic linking problem, which is to link s i to an attribute a i , which is the label of the i th attribute in the entity description vector.
we wish to maximize the probability of the attribute label sequence a given the segments of the noun phrase: Taking consecutive words with the same attribute label as the same semantic segment, the noun phrase segmentation and semantic linking problem is then: argmax a p (< a 1 , a 2 ,..., a n > | < w 1 , w 2 ,..., w n >) In the tag sequence <a 1 , a 2 , …, a n >, if a i and a i+1 are the same, then w i and w i+1 are assigned to the same semantic segment with tag a i .