A schematic diagram of the neural Relation model. The Bi-LSTM nodes shown here refer to the same LSTM network, which is used for each of the spans. Here, t _n and y _n indicate the token embedding and Entity label prediction for the nth token, respectively, D is the direction bit indicating the direction of the Relation in the text, R is the Relation prediction for this Entity pair and direction, and w is the window width. The two Entities in question run from tokens i to j, and from tokens k to l. The h _t−1 notations indicate that it is the hidden state from the final time step that is used as the output from the LSTM nodes.