Search Results

Documents authored by Najib, Muhammad


Document
Characterising and Verifying the Core in Concurrent Multi-Player Mean-Payoff Games

Authors: Julian Gutierrez, Anthony W. Lin, Muhammad Najib, Thomas Steeples, and Michael Wooldridge

Published in: LIPIcs, Volume 288, 32nd EACSL Annual Conference on Computer Science Logic (CSL 2024)


Abstract
Concurrent multi-player mean-payoff games are important models for systems of agents with individual, non-dichotomous preferences. Whilst these games have been extensively studied in terms of their equilibria in non-cooperative settings, this paper explores an alternative solution concept: the core from cooperative game theory. This concept is particularly relevant for cooperative AI systems, as it enables the modelling of cooperation among agents, even when their goals are not fully aligned. Our contribution is twofold. First, we provide a characterisation of the core using discrete geometry techniques and establish a necessary and sufficient condition for its non-emptiness. We then use the characterisation to prove the existence of polynomial witnesses in the core. Second, we use the existence of such witnesses to solve key decision problems in rational verification and provide tight complexity bounds for the problem of checking whether some/every equilibrium in a game satisfies a given LTL or GR(1) specification. Our approach is general and can be adapted to handle other specifications expressed in various fragments of LTL without incurring additional computational costs.

Cite as

Julian Gutierrez, Anthony W. Lin, Muhammad Najib, Thomas Steeples, and Michael Wooldridge. Characterising and Verifying the Core in Concurrent Multi-Player Mean-Payoff Games. In 32nd EACSL Annual Conference on Computer Science Logic (CSL 2024). Leibniz International Proceedings in Informatics (LIPIcs), Volume 288, pp. 32:1-32:25, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2024)


Copy BibTex To Clipboard

@InProceedings{gutierrez_et_al:LIPIcs.CSL.2024.32,
  author =	{Gutierrez, Julian and Lin, Anthony W. and Najib, Muhammad and Steeples, Thomas and Wooldridge, Michael},
  title =	{{Characterising and Verifying the Core in Concurrent Multi-Player Mean-Payoff Games}},
  booktitle =	{32nd EACSL Annual Conference on Computer Science Logic (CSL 2024)},
  pages =	{32:1--32:25},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-310-2},
  ISSN =	{1868-8969},
  year =	{2024},
  volume =	{288},
  editor =	{Murano, Aniello and Silva, Alexandra},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CSL.2024.32},
  URN =		{urn:nbn:de:0030-drops-196752},
  doi =		{10.4230/LIPIcs.CSL.2024.32},
  annote =	{Keywords: Concurrent games, multi-agent systems, temporal logic, game theory}
}
Document
Concurrent Stochastic Lossy Channel Games

Authors: Daniel Stan, Muhammad Najib, Anthony Widjaja Lin, and Parosh Aziz Abdulla

Published in: LIPIcs, Volume 288, 32nd EACSL Annual Conference on Computer Science Logic (CSL 2024)


Abstract
Concurrent stochastic games are an important formalism for the rational verification of probabilistic multi-agent systems, which involves verifying whether a temporal logic property is satisfied in some or all game-theoretic equilibria of such systems. In this work, we study the rational verification of probabilistic multi-agent systems where agents can cooperate by communicating over unbounded lossy channels. To model such systems, we present concurrent stochastic lossy channel games (CSLCG) and employ an equilibrium concept from cooperative game theory known as the core, which is the most fundamental and widely studied cooperative equilibrium concept. Our main contribution is twofold. First, we show that the rational verification problem is undecidable for systems whose agents have almost-sure LTL objectives. Second, we provide a decidable fragment of such a class of objectives that subsumes almost-sure reachability and safety. Our techniques involve reductions to solving infinite-state zero-sum games with conjunctions of qualitative objectives. To the best of our knowledge, our result represents the first decidability result on the rational verification of stochastic multi-agent systems on infinite arenas.

Cite as

Daniel Stan, Muhammad Najib, Anthony Widjaja Lin, and Parosh Aziz Abdulla. Concurrent Stochastic Lossy Channel Games. In 32nd EACSL Annual Conference on Computer Science Logic (CSL 2024). Leibniz International Proceedings in Informatics (LIPIcs), Volume 288, pp. 46:1-46:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2024)


Copy BibTex To Clipboard

@InProceedings{stan_et_al:LIPIcs.CSL.2024.46,
  author =	{Stan, Daniel and Najib, Muhammad and Lin, Anthony Widjaja and Abdulla, Parosh Aziz},
  title =	{{Concurrent Stochastic Lossy Channel Games}},
  booktitle =	{32nd EACSL Annual Conference on Computer Science Logic (CSL 2024)},
  pages =	{46:1--46:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-310-2},
  ISSN =	{1868-8969},
  year =	{2024},
  volume =	{288},
  editor =	{Murano, Aniello and Silva, Alexandra},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CSL.2024.46},
  URN =		{urn:nbn:de:0030-drops-196894},
  doi =		{10.4230/LIPIcs.CSL.2024.46},
  annote =	{Keywords: concurrent, games, stochastic, lossy channels, wqo, finite attractor property, cooperative, core, Nash equilibrium}
}
Document
Equilibrium Design for Concurrent Games

Authors: Julian Gutierrez, Muhammad Najib, Giuseppe Perelli, and Michael Wooldridge

Published in: LIPIcs, Volume 140, 30th International Conference on Concurrency Theory (CONCUR 2019)


Abstract
In game theory, mechanism design is concerned with the design of incentives so that a desired outcome of the game can be achieved. In this paper, we study the design of incentives so that a desirable equilibrium is obtained, for instance, an equilibrium satisfying a given temporal logic property - a problem that we call equilibrium design. We base our study on a framework where system specifications are represented as temporal logic formulae, games as quantitative concurrent game structures, and players' goals as mean-payoff objectives. In particular, we consider system specifications given by LTL and GR(1) formulae, and show that implementing a mechanism to ensure that a given temporal logic property is satisfied on some/every Nash equilibrium of the game, whenever such a mechanism exists, can be done in PSPACE for LTL properties and in NP/Sigma^P_2 for GR(1) specifications. We also study the complexity of various related decision and optimisation problems, such as optimality and uniqueness of solutions, and show that the complexities of all such problems lie within the polynomial hierarchy. As an application, equilibrium design can be used as an alternative solution to the rational synthesis and verification problems for concurrent games with mean-payoff objectives whenever no solution exists, or as a technique to repair, whenever possible, concurrent games with undesirable rational outcomes (Nash equilibria) in an optimal way.

Cite as

Julian Gutierrez, Muhammad Najib, Giuseppe Perelli, and Michael Wooldridge. Equilibrium Design for Concurrent Games. In 30th International Conference on Concurrency Theory (CONCUR 2019). Leibniz International Proceedings in Informatics (LIPIcs), Volume 140, pp. 22:1-22:16, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2019)


Copy BibTex To Clipboard

@InProceedings{gutierrez_et_al:LIPIcs.CONCUR.2019.22,
  author =	{Gutierrez, Julian and Najib, Muhammad and Perelli, Giuseppe and Wooldridge, Michael},
  title =	{{Equilibrium Design for Concurrent Games}},
  booktitle =	{30th International Conference on Concurrency Theory (CONCUR 2019)},
  pages =	{22:1--22:16},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-121-4},
  ISSN =	{1868-8969},
  year =	{2019},
  volume =	{140},
  editor =	{Fokkink, Wan and van Glabbeek, Rob},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.CONCUR.2019.22},
  URN =		{urn:nbn:de:0030-drops-109246},
  doi =		{10.4230/LIPIcs.CONCUR.2019.22},
  annote =	{Keywords: Games, Temporal logic, Synthesis, Model checking, Nash equilibrium}
}
Questions / Remarks / Feedback
X

Feedback for Dagstuhl Publishing


Thanks for your feedback!

Feedback submitted

Could not send message

Please try again later or send an E-mail