Davide Grossi
Tutorial on 01/06, 10h00:
A Crash-Course in Judgment Aggregation
In this tutorial (structured in two parts) I will provide a broad
introduction to the field of Judgment Aggregation (JA). JA is
concerned with the study of collective decision-making on logically
interconnected issues. As such, it is a multi-disciplinary research
area at the interface of Logic and Social Choice Theory and, I will
argue, of Artificial Intelligence. I will motivate the theory,
introduce its basic nuts and bolts, illustrate some of its basic
results, and outline some of its current directions of research.
The tutorial is based on joint work with Gabriella Pigozzi
(LAMSADE).
Talk on 03/06, 15h00:
Gossip and Information Diffusion
In the gossip problem a number $n$ of agents, each one knowing a piece
of information (a secret) unknown to the others, communicate by
one-to-one interactions (e.g., telephone calls). The result of each
call is that the two agents involved in it learn all secrets the other
agent knows at the time of the call. The problem consists in finding a
sequence of calls which disseminates all the secrets among the agents
in the group, and was widely investigated in the 70s and 80s. This
assumes a centralized perspective on information diffusion: a planner
schedules agents' calls. In this talk I develop a decentralized theory
of the gossip problem, where agents perform calls not according to a
centralized schedule, but following individual epistemic protocols
they run in a distributed fashion. These protocols tell the agents
which calls to execute depending on what they know, or do not know,
about the information state of the agents in the group.
The talk reports on joint on-going work with Maduka Attamah
(University of Liverpool), Wiebe van der Hoek (University of
Liverpool), Hans van Ditmarsch (LORIA), Krzysztof Apt (CWI Amsterdam).
(note : this replaces the prviously planned talk on Limited Foresight in Games)