HADOUX Emmanuel

PhD graduated
Team : SMA
Departure date : 02/29/2016

Supervision : Nicolas MAUDET

Co-supervision : BEYNIER Aurélie, WENG Paul

Markovian sequential decision-making in non-stationary environments: application to argumentative debates

In sequential decision-making problems under uncertainty, an agent makes decisions, one after another, considering the current state of the environment where she evolves. In most work, the environment the agent evolves in is assumed to be stationary, i.e., its dynamics do not change over time. However, the stationarity hypothesis can be invalid if, for instance, exogenous events can occur. In this document, we are interested in sequential decision-making in non-stationary environments. We propose a new model named HS3MDP, allowing us to represent non-stationary problems whose dynamics evolve among a finite set of contexts. In order to efficiently solve those problems, we adapt the POMCP algorithm to HS3MDPs. We also present RLCD with SCD, a new method to learn the dynamics of the environments, without knowing a priori the number of contexts. We then explore the field of argumentation problems, where few works consider sequential decision-making. We address two types of problems: stochastic debates (APS) and mediation problems with non-stationary agents (DMP). In this work, we present a model formalizing APS and allowing us to transform them into an MOMDP in order to optimize the sequence of arguments of one agent in the debate. We then extend this model to DMPs to allow a mediator to strategically organize speak-turns in a debate.

Defence : 11/26/2015 - 14h30 - Campus Jussieu, grande salle de visioconférence, Atrium RdC, porte jaune entrée 2

Jury members :

M. Yann Chevaleyre, LIPN, Univ Paris 13 [Rapporteur]
M. Pierre Marquis, CRIL, Univ Artois [Rapporteur]
Mme. Leila Amgoud (Examinatrice) IRIT
M. Olivier Buffet, LORIA/INRIA
M. Patrice Perny (Examinateur) LIP6, Univ Paris 6
M. Nicolas Maudet, LIP6, Univ Paris 6
Mme. Aurélie Beynier, LIP6, Univ Paris 6
M. Paul Weng, SYSU-CMU, Carnegie Mellon
M. Anthony Hunter (Invité) UCL

2013-2018 Publications