@techreport{weko_47896_1,
   author	 = "Tetsuya,Sakai",
   title	 = "Controlling the Penalty on Late Arrival of Relevant Documents in Information Retrieval Evalution with Graded Relevance",
   year 	 = "2006",
   institution	 = "Knowledge Media Laboratory  Toshiba Corporate R&D center",
   number	 = "94(2006-NL-175)",
   month	 = "sep"
}