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arXiv · 2407.09775

Learning Weighted Finite Automata over the Max-Plus Semiring and its Termination

Takamasa Okudono·Masaki Waga·Taro Sekiyama·Ichiro Hasuo
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Abstract

Active learning of finite automata has been vigorously pursued for the purposes of analysis and explanation of black-box systems. In this paper, we study an L*-style learning algorithm for weighted automata over the max-plus semiring. The max-plus setting exposes a "consistency" issue in the previously studied semiring-generic extension of L*: we show that it can fail to maintain consistency of tables, and can thus make equivalence queries on obviously wrong hypothesis automata. We present a theoretical fix by a mathematically clean notion of column-closedness. We also present a nontrivial and reasonably broad class of weighted languages over the max-plus semiring in which our algorithm terminates.

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Takamasa Okudono, Masaki Waga, Taro Sekiyama, Ichiro Hasuo. 2024-07-13. Learning Weighted Finite Automata over the Max-Plus Semiring and its Termination. https://arxiv.org/abs/2407.09775

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