Measuring uncertainty given imprecise attribute values
A consistent and useful treatment of missing and imprecise data is required for database systems. One problem is that when imprecise data are present then the semantics of query evaluation are no longer obvious and uncertainty is introduced. It is proposed that the query result consist of two sets of objects: those where there is complete certainty and those where there is some uncertainty. Furthermore, the uncertainty should be measured and used to rank the objects for presentation. Self-information and entropy are examined as possible measures of uncertainty.
Keywordsdatabases imprecise data uncertainty self-information entropy
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