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arXiv · 2604.20253

Visualising CTL Witnesses and Counterexamples -- Extended Version

Abstract

One of the advantages of LTL over CTL is that the notion of a counterexample is easy to grasp, visualise and process: it is a trace that violates the property at hand. In this paper we propose a notion of evidence for CTL properties on explicit-state models -- which equally serves as witness for satisfied properties and counterexample for violated ones -- and how to visualise it, with the main aim of (human) comprehension. The main contribution consists of a formal model of evidence, a characterisation of minimal evidence per temporal operator, and a concrete, implemented proposal for its visualisation. This is the extended version of a paper published in SPIN 2026, containing the proofs of all results.

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BibTeXRIS

Arend Rensink. 2026-04-22. Visualising CTL Witnesses and Counterexamples -- Extended Version. https://arxiv.org/abs/2604.20253

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