11 research outputs found
Cores of Cooperative Games in Information Theory
Cores of cooperative games are ubiquitous in information theory, and arise
most frequently in the characterization of fundamental limits in various
scenarios involving multiple users. Examples include classical settings in
network information theory such as Slepian-Wolf source coding and multiple
access channels, classical settings in statistics such as robust hypothesis
testing, and new settings at the intersection of networking and statistics such
as distributed estimation problems for sensor networks. Cooperative game theory
allows one to understand aspects of all of these problems from a fresh and
unifying perspective that treats users as players in a game, sometimes leading
to new insights. At the heart of these analyses are fundamental dualities that
have been long studied in the context of cooperative games; for information
theoretic purposes, these are dualities between information inequalities on the
one hand and properties of rate, capacity or other resource allocation regions
on the other.Comment: 12 pages, published at
http://www.hindawi.com/GetArticle.aspx?doi=10.1155/2008/318704 in EURASIP
Journal on Wireless Communications and Networking, Special Issue on "Theory
and Applications in Multiuser/Multiterminal Communications", April 200
Coalitional Games for Transmitter Cooperation in MIMO Multiple Access Channels
Cooperation between nodes sharing a wireless channel is becoming increasingly
necessary to achieve performance goals in a wireless network. The problem of
determining the feasibility and stability of cooperation between rational nodes
in a wireless network is of great importance in understanding cooperative
behavior. This paper addresses the stability of the grand coalition of
transmitters signaling over a multiple access channel using the framework of
cooperative game theory. The external interference experienced by each TX is
represented accurately by modeling the cooperation game between the TXs in
\emph{partition form}. Single user decoding and successive interference
cancelling strategies are examined at the receiver. In the absence of
coordination costs, the grand coalition is shown to be \emph{sum-rate optimal}
for both strategies. Transmitter cooperation is \emph{stable}, if and only if
the core of the game (the set of all divisions of grand coalition utility such
that no coalition deviates) is nonempty. Determining the stability of
cooperation is a co-NP-complete problem in general. For a single user decoding
receiver, transmitter cooperation is shown to be \emph{stable} at both high and
low SNRs, while for an interference cancelling receiver with a fixed decoding
order, cooperation is stable only at low SNRs and unstable at high SNR. When
time sharing is allowed between decoding orders, it is shown using an
approximate lower bound to the utility function that TX cooperation is also
stable at high SNRs. Thus, this paper demonstrates that ideal zero cost TX
cooperation over a MAC is stable and improves achievable rates for each
individual user.Comment: in review for publication in IEEE Transactions on Signal Processin
Coalitional games for downlink multicell beamforming
A coalitional game is proposed for multi-cell multiuser downlink beamforming. Each base station intends to minimize its transmission power while aiming to attain a set of target signal-to-interference-plus-noise-ratio (SINRs) for its users. In order to reduce power consumption, base stations have incentive to cooperate with other base stations to mitigate intercell interference. The coalitional game is introduced where base stations are allowed to forge partial cooperation rather than full cooperation. The partition form coalitional game is formulated with the consideration that beamformer
design of a coalition depends on the coalition structure outside the considered coalition. We first formulate the beamformer
design for a given coalition structure, in which base stations in a coalition greedily minimize the total weighted transmit
power without considering interference leakage to users in other coalitions. This can be considered as a non-cooperative game
with each player as a distinct coalition. By introducing cost for cooperation, the coalition formation game is considered for the power minimization based beamforming. A merge-regret based sequential coalition formation algorithm has been developed that
is capable of reaching a unique stable coalition structure. Finally, an α-Modification algorithm has been proposed to improve the performance of the coalition formation algorithm
Information Inequalities for Joint Distributions, with Interpretations and Applications
Upper and lower bounds are obtained for the joint entropy of a collection of
random variables in terms of an arbitrary collection of subset joint entropies.
These inequalities generalize Shannon's chain rule for entropy as well as
inequalities of Han, Fujishige and Shearer. A duality between the upper and
lower bounds for joint entropy is developed. All of these results are shown to
be special cases of general, new results for submodular functions-- thus, the
inequalities presented constitute a richly structured class of Shannon-type
inequalities. The new inequalities are applied to obtain new results in
combinatorics, such as bounds on the number of independent sets in an arbitrary
graph and the number of zero-error source-channel codes, as well as new
determinantal inequalities in matrix theory. A new inequality for relative
entropies is also developed, along with interpretations in terms of hypothesis
testing. Finally, revealing connections of the results to literature in
economics, computer science, and physics are explored.Comment: 15 pages, 1 figure. Originally submitted to the IEEE Transactions on
Information Theory in May 2007, the current version incorporates reviewer
comments including elimination of an erro
Coalitional Game Theory for Communication Networks: A Tutorial
Game theoretical techniques have recently become prevalent in many
engineering applications, notably in communications. With the emergence of
cooperation as a new communication paradigm, and the need for self-organizing,
decentralized, and autonomic networks, it has become imperative to seek
suitable game theoretical tools that allow to analyze and study the behavior
and interactions of the nodes in future communication networks. In this
context, this tutorial introduces the concepts of cooperative game theory,
namely coalitional games, and their potential applications in communication and
wireless networks. For this purpose, we classify coalitional games into three
categories: Canonical coalitional games, coalition formation games, and
coalitional graph games. This new classification represents an
application-oriented approach for understanding and analyzing coalitional
games. For each class of coalitional games, we present the fundamental
components, introduce the key properties, mathematical techniques, and solution
concepts, and describe the methodologies for applying these games in several
applications drawn from the state-of-the-art research in communications. In a
nutshell, this article constitutes a unified treatment of coalitional game
theory tailored to the demands of communications and network engineers.Comment: IEEE Signal Processing Magazine, Special Issue on Game Theory, to
appear, 2009. IEEE Signal Processing Magazine, Special Issue on Game Theory,
to appear, 200
Resource allocation in networks via coalitional games
The main goal of this dissertation is to manage resource allocation in network
engineering problems and to introduce efficient cooperative algorithms to obtain high performance, ensuring fairness and stability. Specifically, this dissertation introduces
new approaches for resource allocation in Orthogonal Frequency Division Multiple Access (OFDMA) wireless networks and in smart power grids by casting the problems to the coalitional game framework and by providing a constructive iterative algorithm based on dynamic learning theory.
Software Engineering (Software)Algorithms and the Foundations of Software technolog