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arXiv · 2606.08297

Strategic Type Spaces

Olivier Gossner·Rafael Veiel
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Abstract

We provide a strategic foundation for information: in any given game with incomplete information we define strategic quotients as information representations that are sufficient for players to compute best-responses to other players. We prove 1/ existence and essential uniqueness of a minimal strategic quotient called the Strategic Type Space (STS) in which a type is given by an interim correlated rationalizability hierarchy and represents a set of beliefs over other players' types and nature that rationalize this hierarchy and 2/ that the minimal STS has a recursive structure that is captured by a finite automaton.

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Olivier Gossner, Rafael Veiel. 2026-06-06. Strategic Type Spaces. https://arxiv.org/abs/2606.08297

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