Threshold-based Probabilistic Top-k Dominating Querie ÕªÒª´ÖÒë
Abstract Recently, due to intrinsic characteristics in many underlying data sets, a number of probabilistic queries on uncertain data have been investigated. Top-k dominating queries are very important in many applications including decision making in a multidimen-
sional space. In this paper, we study the problem of efficiently computing top-k dominating queries on uncertain data. We frst formally de¡¥ne the problem. Then, we develop an e¡Àcient, threshold-based algorithm to compute the exact solution. To overcome some inherent computational de¡¥ciency in an exact computation, we develop an e¡Àcient randomized algorithm with an accuracy guar-antee. Our extensive experiments demonstrate that both algorithms are quite e¡Àcient, while the randomized algorithm is quite scalable against data set sizes, object areas, k values, etc. The randomized algorithm is also highly accurate in practice.
Keywords Uncertain Objects Top k Dominating Relation
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