While these neural span features cannot be used in BIO-based SRL models, they can easily be incorporated into spanbased models.
taking a span representation h s as input, the labeling function f label returns the score for the span s = (i, j) with a label r. we use the following labeling function, where W ∈ R |R|×2d hidden has a row vector associated with each label r, and W[r] denotes the r-th row vector.