Feature Engineering for Drug Name Recognition in Biomedical Texts: Feature Conjunction and Feature Selection

Table 1

Singleton feature templates.

Number	Feature template
	Word feature
	POS
	Chunk
	Orthographical feature
	DrugBank
	FDA
	Jochem
	Word embeddings feature
	Prefix of length of 3
	Prefix of length of 4
	Prefix of length of 5
	Suffix of length of 3
	Suffix of length of 4
	Suffix of length of 5
	Word shape (generalized word class)
	Word shape (brief word class)