Then, for each cell, we throw out any item that has a score worse than: r β plus the best score in the same cell, or r the score of the bth best item in the same cell.
in the +LM parser, the score of an item [X, i, j; e] in the chart does not reflect the LM probability of generating the first (m − 1) words of e. two items [X, i, j; e] and [X, i, j; e ] are not directly comparable.