Subroutine ContextSimilarity (E 1 , E 2 , Θ CD ) generates a context vector (CV) for each event cluster and check whether cosine similarity between context vectors of two clusters E 1 and E 2 (cos( CV 1 , CV 2 )) is above 0.7.
we define context clusters for an event mention as the different event clusters that have event mentions co-occurring in the same sentence.