We follow Miwa and Bansal 2016  Different from Miwa and Bansal (2016), who use the output hidden vectors {h i } of LSTMs to represent words, we exploit segment representations as well.
for a segment of text [i, j], the representation is computed by using LSTM-Minus (Wang and Chang, 2016), shown by Figure 4, where h j − h i−1 in a left-to-right LSTM and h i − h j+1 in a right-to-left LSTM are used to represent the segment [i, j].