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arXiv · 2111.08300

Highly Efficient Indexing Scheme for k-Dominant Skyline Processing over Uncertain Data Streams

Chuan-Chi Lai·Hsuan-Yu Lin·Chuan-Ming Liu
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Abstract

Skyline is widely used in reality to solve multi-criteria problems, such as environmental monitoring and business decision-making. When a data is not worse than another data on all criteria and is better than another data at least one criterion, the data is said to dominate another data. When a data item is not dominated by any other data item, this data is said to be a member of the skyline. However, as the number of criteria increases, the possibility that a data dominates another data decreases, resulting in too many members of the skyline set. To solve this kind of problem, the concept of the k-dominant skyline was proposed, which reduces the number of skyline members by relaxing the limit. The uncertainty of the data makes each data have a probability of appearing, so each data has the probability of becoming a member of the k-dominant skyline. When a new data item is added, the probability of other data becoming members of the k-dominant skyline may change. How to quickly update the k-dominant skyline for real-time applications is a serious problem. This paper proposes an effective method, Middle Indexing (MI), which filters out a large amount of irrelevant data in the uncertain data stream by sorting data specifically, so as to improve the efficiency of updating the k-dominant skyline. Experiments show that the proposed MI outperforms the existing method by approximately 13% in terms of computation time.

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Chuan-Chi Lai, Hsuan-Yu Lin, Chuan-Ming Liu. 2021-11-16. Highly Efficient Indexing Scheme for k-Dominant Skyline Processing over Uncertain Data Streams. https://doi.org/10.1109/wocc53213.2021.9603141

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