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arXiv · 2411.02013

Classement d'objets Skylines dans les bases de donn{\'e}es

Mickaël Martin-Nevot·Lotfi Lakhal
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Abstract

Multi-criteria decision analysis in databases has been actively studied, especially through the Skyline operator. Yet, few approaches offer a relevant comparison of Pareto optimal, or Skyline, points for high cardinality result sets. We propose to improve the dp-idp method, inspired by tf-idf, a recent approach computing a score for each Skyline point, by introducing the concept of dominance hierarchy. As dp-idp does not ensure a distinctive rank, we introduce the TOPSIS based CoSky method, derived from both information research and multi-criteria analysis. CoSky, directly embeddable in DBMS, automatically ponderates normalized attributes using the Gini index, then computes a score using Salton's cosine toward an ideal point. By coupling multilevel Skyline to CoSky, we introduce DeepSky. CoSky and dp-idp implementations are evaluated experimentally.

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Mickaël Martin-Nevot, Lotfi Lakhal. 2024-11-04. Classement d'objets Skylines dans les bases de donn{\'e}es. https://arxiv.org/abs/2411.02013

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