9 The output of this processing is a repository of structured objects (with POS tags, dependency parse, and entity types and mentions) for sentences from the training corpus.
for each pair of entity mentions (m 1 , m 2 ) in a sentence, we extract the following features F (m 1 , m 2 ): (1) the word sequence (including POS tags) between these mentions after normalizing entity mentions (e.g., replacing "John Nolen" with a place holder PER); if the sequence is longer than 6, we take the 3-word prefix and the 3-word suffix; (2) the dependency path between the mention pair.