4 Bottom-up tree-building For both intra-and multi-sentential parsing, our bottom-up tree-building process adopts a similar greedy pipeline framework like the HILDA discourse parser (discussed in Section 2.1), to guarantee efficiency for large documents.
starting from the constituents on the bottom level (EDUs for intra-sentential parsing and sentence-level discourse trees for multi-sentential parsing), at each step of the tree-building, we greedily merge a pair of adjacent discourse constituents such that the merged constituent has the highest probability as predicted by our structure model.