Recommending High Utility Queries via Query-Reformulation Graph

Table 2

Comparison of document relevance of three methods. (The percentages in the parentheses are the improvement of our QRG method over the corresponding methods).

Method	SDF	DF	QRG
@5	0.614 (10.4%)	0.634 (6.8%)	0.678
@10	0.562 (11.8%)	0.578 (8.8%)	0.629
@15	0.490 (21.7%)	0.513 (16.2%)	0.596
@20	0.440 (30.4%)	0.453 (26.7%)	0.573
DCG@5	2.693 (9.4%)	2.780 (5.9%)	2.945
DCG@10	3.870 (10.6%)	3.985 (7.4%)	4.279
DCG@15	4.529 (16.8%)	4.716 (12.2%)	5.290
DCG@20	5.022 (22.5%)	5.180 (18.7%)	6.150