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Strategic Conversations Under Imperfect Information: Epistemic Message Exchange Games

December 2018
Journal of Logic Language and Information 27(2)

Authors:

Toulouse Institute of Computer Science Research

This paper refines the game theoretic analysis of conversations in Asher et al. (J Philos Logic 46:355–404, 2017) by adding epistemic concepts to make explicit the intuitive idea that conversationalists typically conceive of conversational strategies in a situation of imperfect information. This ‘epistemic’ turn has important ramifications for linguistic analysis, and we illustrate our approach with a detailed treatment of linguistic examples. © 2018 Springer Science+Business Media B.V., part of Springer Nature

The ME game tree for the conversation in Example 1

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The ME game tree for the conversation in Example 3

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An ME game structure for the initial part of the conversation between R and S. The nodes represent the EDUs and the rectangular boxes represent the CDUs as given in the description of ρ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\rho $$\end{document}

…

Two histories resulting from two different interpretations of the uninterpreted relations in ρ\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\rho $$\end{document}

…

The ME game of Example 9 after ρ5\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\rho _5$$\end{document}

…

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J Log Lang Inf (2018) 27:343–385

https://doi.org/10.1007/s10849-018-9271-9

Strategic Conversations Under Imperfect Information:

Epistemic Message Exchange Games

Nicholas Asher1·Soumya Paul2

Published online: 4 June 2018

Abstract This paper reﬁnes the game theoretic analysis of conversations in Asher et al.

(J Philos Logic 46:355–404, 2017) by adding epistemic concepts to make explicit the

intuitive idea that conversationalists typically conceive of conversational strategies in

a situation of imperfect information. This ‘epistemic’ turn has important ramiﬁcations

for linguistic analysis, and we illustrate our approach with a detailed treatment of

linguistic examples.

Keywords Strategic conversations ·Epistemic game theory ·Discourse representation

theory

1 Introduction

It has long been a common sense intuition of many philosophical and linguistic theories

of communication that a conversational contribution should be interpreted in light of

the participants’ own beliefs and plans, in particular their beliefs about beliefs and

Thanks to Julie Hunter, Alex Lascarides, David Beaver, Eric McCready, Daisuke Bekki, Chris Barker,

Erich Grädel, Hans Kamp, Benedikt Löwe, Julian Schlöder, Itai Sher, to the participants of the Rutgers

Workshop on Coordination and Content and to reviewers for the Journal of Logic, Language and

Information for their helpful comments on previous versions of this paper. This work was supported by

ERC Grant 269427.

BSoumya Paul

soumya.paul@gmail.com

Nicholas Asher

nicholas.asher@irit.fr

1IRIT, CNRS, Université Paul Sabatier, 118 route de Narbonne, 31062 Toulouse, France

2SnT, Université du Luxembourg, 6 avenue de la Fonte, L-4364 Esch-sur-Alzette, Luxembourg

123

Content courtesy of Springer Nature, terms of use apply. Rights reserved.

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