Now showing items 21-40 of 40

    • Network formation for asymmetric players and bilateral contracting 

      Álvarez Faura, M. del Carme; Serna Iglesias, María José; Fernández, Aleix (2016-10-01)
      Article
      Open Access
      We study a network formation game where players wish to send traffic to other players. Players can be seen as nodes of an undirected graph whose edges are defined by contracts between the corresponding players. Each player ...
    • On the existence of Nash equilibria in strategic search games 

      Álvarez Faura, M. del Carme; Duch Brown, Amalia; Serna Iglesias, María José; Thilikos Touloupas, Dimitrios (2011)
      Conference report
      Open Access
      We consider a general multi-agent framework in which a set of n agents are roaming a network where m valuable and sharable goods (resources, services, information ....) are hidden in m different vertices of the network. ...
    • On the price of anarchy for high-price links 

      Álvarez Faura, M. del Carme; Messegué Buisan, Arnau (Springer, 2019)
      Conference report
      Open Access
      We study Nash equilibria and the price of anarchy in the classic model of Network Creation Games introduced by Fabrikant, Luthra, Maneva, Papadimitriou and Shenker in 2003. This is a selfish network creation model where ...
    • On the proper intervalization of colored caterpillar trees 

      Álvarez Faura, M. del Carme; Serna Iglesias, María José (2009-11-01)
      External research report
      Open Access
      This paper studies the computational complexity of the Proper interval colored graph problem (picg), when the input graph is a colored caterpillar, parameterized by hair length. In order prove our result we establish a ...
    • On the proper intervalization of colored caterpillar trees 

      Álvarez Faura, M. del Carme; Serna Iglesias, María José (2009)
      Article
      Restricted access - publisher's policy
      This paper studies the computational complexity of the proper interval colored graph problem (picg), when the input graph is a colored caterpillar, parameterized by hair length. In order prove our result we establish a ...
    • Parallel complexity in the design and analysis of concurrent systems 

      Álvarez Faura, M. del Carme; Balcázar Navarro, José Luis; Gabarró Vallès, Joaquim (1990-10)
      External research report
      Open Access
      We study the parallel complexity of three problems on concurrency: decision of firing sequences for Petri nets, trace equivalence for partially commutative monoids, and strong bisimilarity in finite transition systems. We ...
    • Parallel complexity of partially commutative monoids 

      Álvarez Faura, M. del Carme; Gabarró Vallès, Joaquim (1989-01)
      External research report
      Open Access
      We consider the parallel complexity of some problems issued from Petri nets, partially commutative monoids and finite automata. we prove the following: (19 The membership problem for firing sequances on Petri Nets can be ...
    • PSPACE suffices for deciding nash equilibria properties for extensive games with large trees 

      Álvarez Faura, M. del Carme; Gabarró Vallès, Joaquim; Serna Iglesias, María José (2005-09)
      External research report
      Open Access
      We study the computational complexity of deciding the existence of a Pure Nash Equilibrium or a subgame perfect equilibrium with a given payoff and other related problems in finite multi-player extensive games with perfect ...
    • Pure Nash equilibria in games with a large number of actions 

      Álvarez Faura, M. del Carme; Gabarró Vallès, Joaquim; Serna Iglesias, María José (2004-11)
      External research report
      Open Access
      We study the computational complexity of deciding the existence of a Pure Nash Equilibrium in multi-player strategic games. We address two fundamental questions: how can we represent a game?, and how can we represent a ...
    • Sensor field: a computational model 

      Álvarez Faura, M. del Carme; Duch Brown, Amalia; Gabarró Vallès, Joaquim; Serna Iglesias, María José (2009)
      Article
      Restricted access - publisher's policy
      We introduce a formal model of computation for networks of tiny artifacts, the static synchronous sensor field model (SSSF) which considers that the devices communicate through a fixed communication graph and interact ...
    • Sensor field: a computational model 

      Álvarez Faura, M. del Carme; Duch Brown, Amalia; Gabarró Vallès, Joaquim; Serna Iglesias, María José (2009-09-23)
      External research report
      Open Access
      We introduce a formal model of computation for networks of tiny artifacts, the static synchronous sensor field model (SSSF) which considers that the devices communicate through a fixed communication graph and interact ...
    • Sensor field: a computational model 

      Álvarez Faura, M. del Carme; Duch Brown, Amalia; Gabarró Vallès, Joaquim; Serna Iglesias, María José (2009)
      Conference lecture
      Open Access
      In this work we introduce a formal model for studying networks of tiny artifacts, the static synchronous sensor field model (SSSF). The model consider that these devices communicate among them by means of a communication ...
    • Stars and celebrities: A network creation game 

      Álvarez Faura, M. del Carme; Blesa Aguilera, Maria Josep; Duch Brown, Amalia; Messegué Buisan, Arnau; Serna Iglesias, María José (2015)
      External research report
      Open Access
      Celebrity games, a new model of network creation games is introduced. The specific features of this model are that players have different celebrity weights and that a critical distance is taken into consideration. The aim ...
    • The Complexity of deciding stability under FFS in the adversarial model 

      Álvarez Faura, M. del Carme; Blesa Aguilera, Maria Josep; Díaz Cort, Josep; Fernández Anta, Antonio; Serna Iglesias, María José (2003-04)
      External research report
      Open Access
      In this paper we show the polynomial time decidability of the stability property under FFS in the case that the adversary can solve ties arbitrarily. This results follows from a characterization of the stability property ...
    • The Complexity of pure Nash equilibria in weighted Max-Congestion Games 

      Álvarez Faura, M. del Carme; Francès Medina, Guillem (Universitat Politècnica de Catalunya. Departament de Llenguatges i Sistemes Informàtics, 2008-03-04)
      External research report
      Open Access
      We study Network Max-Congestion Games (NMC games, for short), a class of network games where each player tries to minimize the most congested edge along the path he uses as strategy. We focus our study on the complexity ...
    • The Hardness of intervalizing four colored caterpillars 

      Serna Iglesias, María José; Díaz Iriberri, José; Álvarez Faura, M. del Carme (1998-07-02)
      External research report
      Open Access
      The problem of Intervalizing Colored Graphs (ICG) has received a lot of attention due to their use as a model for DNA physical mapping with ambiguous data. If k is the number of colors, the problem is known to be NP-Complete ...
    • The HOM problem is decidable 

      Godoy, Guillem; Giménez, Omer; Ramos Garrido, Lander; Álvarez Faura, M. del Carme (2009-06)
      External research report
      Open Access
      We close affirmatively a question which has been open for 35 years: decidability of the HOM problem. The HOM problem consists in deciding, given a tree homomorphism $H$ and a regular tree languagle $L$ represented by a ...
    • The Proper interval colored graph problem for caterpillar trees 

      Álvarez Faura, M. del Carme; Serna Iglesias, María José (1999-04)
      External research report
      Open Access
      This paper studies the computational complexity of the Proper Interval Colored Graph problem (PICG), when the input graph is a colored tree. We show that the problem is hard for the class of caterpillar trees. To prove ...
    • The robustness of stability under link and node failures 

      Álvarez Faura, M. del Carme; Blesa Aguilera, Maria Josep; Serna Iglesias, María José (2007-07)
      External research report
      Open Access
      In the area of communication systems, stability refers to the property of keeping the amount of traffic in the system always bounded over time. Different communication system models have been proposed in order to capture ...
    • Universal stability of undirected graphs in the adversarial queueing model 

      Álvarez Faura, M. del Carme; Serna Iglesias, María José; Blesa Aguilera, Maria Josep (2002-03)
      External research report
      Open Access
      In this paper we study the universal stability of undirected graphs in the adversarial queueing model for packet routing. In this setting packets must be injected in some edge and have to traverse a path before leaving ...