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arXiv · 1305.4288

Upwards Closed Dependencies in Team Semantics

Pietro Galliani
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Abstract

We prove that adding upwards closed first-order dependency atoms to first-order logic with team semantics does not increase its expressive power (with respect to sentences), and that the same remains true if we also add constancy atoms. As a consequence, the negations of functional dependence, conditional independence, inclusion and exclusion atoms can all be added to first-order logic without increasing its expressive power. Furthermore, we define a class of bounded upwards closed dependencies and we prove that unbounded dependencies cannot be defined in terms of bounded ones.

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Pietro Galliani. 2013-07-17. Upwards Closed Dependencies in Team Semantics. https://doi.org/10.4204/eptcs.119.10

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