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arXiv · 2307.05062

System of Spheres-based Two Level Credibility-limited Revisions

Marco Garapa·Eduardo Ferme·Maurício D. L. Reis
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Abstract

Two level credibility-limited revision is a non-prioritized revision operation. When revising by a two level credibility-limited revision, two levels of credibility and one level of incredibility are considered. When revising by a sentence at the highest level of credibility, the operator behaves as a standard revision, if the sentence is at the second level of credibility, then the outcome of the revision process coincides with a standard contraction by the negation of that sentence. If the sentence is not credible, then the original belief set remains unchanged. In this paper, we propose a construction for two level credibility-limited revision operators based on Grove's systems of spheres and present an axiomatic characterization for these operators.

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Marco Garapa, Eduardo Ferme, Maurício D. L. Reis. 2023-07-11. System of Spheres-based Two Level Credibility-limited Revisions. https://doi.org/10.4204/eptcs.379.23

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