For the 10 categories of Table 1 used in previous work, we  have obtained (P=92,T=41) which outperforms the seed-based concept acquisition of (Widdows and Dorow, 2002;Davidov and Rappoport, 2006) (P=90,T=35) on the same concepts.
the two main algorithmic approaches are pattern-based discovery, and clustering of context feature vectors.