SPHLU: An Efficient Algorithm for Processing PRkNN Queries on Uncertain Data

Query on uncertain data has received much attention in recent years, especially with the development of Location-based services (LBS). Little research is focused on reverse k nearest neighbor queries on uncertain data. We study the Probabilistic reverse k nearest neighbor (PRkNN) queries on uncertain data. It is succinctly shown that, PRkNN query retrieves all the points that have higher probabilities than a given threshold value to be the Reverse k-nearest neighbor (RkNN) of query data Q. The previous works on this topicmostly process with k > 1. Some algorithms allow the cases for k > 1, but the efficiency is inefficient especially for large k. We propose an efficient pruning algorithm-Spatial pruning heuristic with louer and upper bound (SPHLU) for solving the PRkNN queries for k > 1. The experimental results demonstrate that our algorithm is even more efficient than the existent algorithms especial for a large value of k.