Answering Top K Queries Efficiently with Overlap in Sources and Source Paths
نویسندگان
چکیده
Challenges in answering queries over Web-accessible sources are selecting the sources that must be accessed and computing answers efficiently. Both tasks become more difficult when there is overlap among sources and when sources may return answers of varying quality. The objective is to obtain the best answers while minimizing the costs or delay in computing these answers and is similar to solving a Top K problem efficiently. We motivate these problems and discuss solution approaches.
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