@inproceedings{SIGIR-2003-Sakai,
	author        = "Tetsuya Sakai",
	booktitle     = "{Proceedings of the 26th International ACM SIGIR Conference on Research and Development in Information Retrieval}",
	doi           = "10.1145/860435.860529",
	isbn          = "1-58113-646-3",
	pages         = "417--418",
	publisher     = "{ACM}",
	title         = "{Average gain ratio: a simple retrieval performance measure for evaluation with multiple relevance levels}",
	year          = 2003,
}