Table 1.

Data specification

Corpus	Domain	Set	Article	Sentence	Token	Entity
i2b2 2012	Clinical	Train	190	7,258	94,836	11,239
		Test	120	5,547	78,564	9,623
SNUH	Clinical	Train	196	11,669	116,402	18,383
		Test	193	11,042	107,666	17,125
CoNLL 2003	General	Train	946	14,987	203,621	23,499
		Test	231	3,684	46,435	5,629