Table 1.

Fraction of relevant abstracts retrieved for all questions. The last column shows the total number of relevant citations retrieved for each condition (out of 90).

Condition	Rank			Total	Number
	1	2	3
Baseline	0.33	0.36	0.30	0.33	30
Lexical	0.30	0.36	0.36	0.33	30
Semantic1	0.40	0.40	0.36	0.38	35
Semantic2	0.63	0.70	0.53	0.62	56
Semantic3	0.63	0.53	0.56	0.58	52