The external validity of causal findings is a focus long-standing debates in the social sciences. Although issue has been extensively studied at conceptual level, practice few empirical studies include an explicit analysis that directed toward externally valid inferences. In this article, we make three contributions to improve approaches for validity. First, propose formal framework encompasses...

Representing an epistemic situation involving several agents depends very much on the modeling point of view one takes. In fact, the interpretation of a formalism relies quite a lot on the nature of this modeling point of view. Classically, in epistemic logic, the models built are supposed to represent the situation from an external and objective point of view. We call this modeling approach th...

In this article, we introduce an epistemic modal operator modelling knowledge over distributive non-associative full Lambek calculus with a negation. Our approach is based on the relational semantics for substructural logics: we interpret the elements of a relational frame as information states consisting of collections of data. The principal epistemic relation between the states is the one of ...

Epistemic logic allows to reason not only about situations, but also about the knowledge that a set of agents have about situations. In later years, epistemic logic has been applied to study the role of knowledge in games and negotiations. The classical approach, the mathematical theory of games, does not facilitate explicit reasoning about the knowledge of the agents that interact in competiti...

Given n agents each of which has a secret (a fact not known to anybody else), the classical version of the gossip problem is to achieve shared knowledge of all secrets in a minimal number of phone calls. There exist protocols achieving shared knowledge in 2(n−2) calls: when the protocol terminates everybody knows all the secrets. We generalize that problem and focus on higher-order shared knowl...