International Society of Dynamic Games

  • DGA Seminar: Georges Zaccour

    Georges Zaccour
    Department of Decision Sciences HEC Montréal

    Dynamic Games and Applications Seminar

    Dynamic Games Played over Event Trees with Coupling Constraints

    April 18, 2024 11:00 AM — 12:00 PM (Montreal time)

    Zoom webinar link

    In this talk, I will first present the framework of dynamic games played over event trees (DGPETs) and characterize Nash equilibrium in a setup where the players’ action sets are interdependent. Second, I will illustrate the theory with a model where a set of competing firms procure a product from the same supplier that faces a capacity constraint, including a possible complete shortage, which binds together the ordering strategies of the firms. Numerical results are discussed.
    (The second part is a paper with Elena Parilina and Stefan Wrzaczek.)

  • DGA Seminar: Michel Grabisch

    Michel Grabisch
    Université Paris 1

    Dynamic Games and Applications Seminar

    On the design of public debate in social network

    April 11, 2024 11:00 AM — 12:00 PM (Montreal time)

    Zoom webinar link

    We propose a model of the joint evolution of opinions and social relationships in a setting where social influence decays over time. The dynamics are based on bounded confidence: social connections between individuals with distant opinions are severed while new connections are formed between individuals with similar opinions. Our model naturally gives raise to strong diversity, i.e., the persistence of heterogeneous opinions in connected societies, a phenomenon that most existing models fail to capture. The intensity of social interactions is the key parameter that governs the dynamics. First, it determines the asymptotic distribution of opinions. In particular, increasing the intensity of social interactions brings society closer to consensus. Second, it determines the risk of polarization, which is shown to increase with the intensity of social interactions. Our results allow to frame the problem of the design of public debates in a formal setting. We hence characterize the optimal strategy for a social planner who controls the intensity of the public debate and thus faces a trade-off between the pursuit of social consensus and the risk of polarization. We also consider applications to political campaigning and show that both minority and majority candidates can have incentives to lead society towards polarization.

    (with A. Mandel and A. Rusinowska).

  • DGA Seminar: Chantal Marlats

    Chantal Marlats
    Université Panthéon-Assas
    Paris II

    Dynamic Games and Applications Seminar

    The social value of information in times of epidemic

    April 4, 2024 11:00 AM — 12:00 PM (Montreal time)

    Zoom webinar link

    We analyze an epidemiological model in which individuals trade the costs and benefits of self-isolation while being uncertain about both their type and the dynamics of the epidemic. We characterize the unique symmetric equilibrium and show that uncertainty can be the cause of an additional wave of infections. We calibrate our model to the COVID-19 pandemic and simulate the dynamics of the epidemic under various scenarios to illustrate the impact of uncertainty on self-isolation behaviors. We show that uncertainty about the epidemic dynamics may be welfare improving, both in terms of fraction of deaths and average payoffs. (with Dominique Baril-Tremblay and Lucie Ménager)