Proceedings of the 13th ACM SIGKDD international conference on Knowledge discovery and data mining
Optimal Preference Elicitation for Skyline Queries over Categorical Domains
DEXA '08 Proceedings of the 19th international conference on Database and Expert Systems Applications
Efficient skyline querying with variable user preferences on nominal attributes
Proceedings of the VLDB Endowment
Personalized top-k skyline queries in high-dimensional space
Information Systems
Minimal contraction of preference relations
AAAI'08 Proceedings of the 23rd national conference on Artificial intelligence - Volume 1
Eliciting matters: controlling skyline sizes by incremental integration of user preferences
DASFAA'07 Proceedings of the 12th international conference on Database systems for advanced applications
Preference elicitation in prioritized skyline queries
The VLDB Journal — The International Journal on Very Large Data Bases
Contracting preference relations for database applications
Artificial Intelligence
Transitivity-preserving skylines for partially ordered domains
DASFAA'10 Proceedings of the 15th international conference on Database Systems for Advanced Applications - Volume Part II
Information Sciences: an International Journal
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Unlike numerical preferences, preferences on at-tribute values do not show an inherent total order, but skyline computation has to rely on partial orderings explicitly stated by the user. In such orders many ob-ject values are incomparable, hence skylines sizes become unpractical. However, the Pareto semantics can be modified to benefit from indifferences: skyline result sizes can be essentially reduced by allowing the user to declare some incomparable values as equally desirable. A major problem of adding such equiva-lences is that they may result in intransitivity of the aggregated Pareto order and thus efficient query proc-essing is hampered. In this paper we analyze how far the strict Pareto semantics can be relaxed while al-ways retaining transitivity of the induced Pareto ag-gregation. Extensive practical tests show that skyline sizes can indeed be reduced about two orders of mag-nitude when using the maximum possible relaxation still guaranteeing the consistency with all user prefer-ences.