The EDPM metric (Kahn et al., 2010) improves this line of research by using arc labels derived from a Probabilistic Context-Free Grammar (PCFG) parse to replace the LFG labels, showing that a PCFG parser is sufficient for preprocessing, compared to a dependency parser in (Liu and Gildea, 2005) and <cite>(Owczarzak et al., 2007)</cite> .