Table 4.

F-scores using lexical and semantic Information for 6-way and 5-way classification.

Feature	6-way		5-way
		S	U	S	U
1.P	70.42	60.82	81.68	68.51
2.P	47.50	44.19	59.09	49.61
Token-CUI	66.19	59.47	78.26	65.57
Token-Syn	64.13	58.79	76.77	65.47
Token-Syn-B	65.25	59.94	77.43	66.22
MetaMap-CUI	56.08	52.23	64.58	56.58

1.P: unigrams with POS, 2.P: bigrams with POS, CUI: UMLS tag, Syn: expansion with synonyms, Syn-B: synonyms in break-down form. Best results per column are given in bold.