in factorization based methods for learning word embeddings (Turney and Pantel, 2010).
we express the strength of association between words w i and w j as follows: In our case, x ij is the number of times word w i appears near word w j , weighted by the nearness of their co-occurrences, and let I w i be the word positions in the corpus at which w i occurs, then we define: where n(p, q) = 0 if the word positions p and q belong to a different sentence, or if |p − q| > 10, i.e.