Wei Cheng, Xiaoming Jin, and Jian-Tao Sun
Retrieving similar data has drawn many research efforts in literature due to its importance in data mining, database, and information retrieval. This problem is challenging when the data is incomplete. In previous research, data incompleteness refers to the fact that data values for some dimensions are unknown. However, in many practical applications (e.g., data collection by sensor network under bad environment), not only data values but even data dimension information may also be missing, which will make most similarity query algorithms infeasible. In this work, we proposed the novel similarity query problem on dimension incomplete data and adopted a probabilistic framework to model this problem. For this problem, users can specify a distance threshold and a probability threshold to specify their retrieval requirements. The distance threshold is used to specify the allowed distance between query and data objects
and the probability threshold is used to require that the retrieval results satisfy the distance condition at least with the given probability. Instead of enumerating all possible cases to recover the missed dimensions, we propose an efficient approach to speed up the retrieval process by leveraging
inherent relations between query and dimension incomplete data objects. When query is processed, we estimate the lower/upper bounds of the probability that the query is satisfied by a given data object, and utilize these bounds in filtering data objects efficiently. Furthermore, a probabilistic triangle inequality is proposed to further speed up query processing. According to experiments on real data sets, our similarity query method is verified to be effective and effi
cient on dimension incomplete data.
In The 2009 edition of the IEEE International Conference on Data Mining series (ICDM 2009)
Publisher IEEE Communications Society
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