International Society of Dynamic Games

Dynamic Games and Applications Seminar

Cooperation, Competition, and Common Pool Resources in Mean Field Games

Nov 6, 2025   11:00 AM — 12:00 PM (Montreal time)

Zoom webinar link

The tragedy of the commons (TOTC, introduced by Hardin in 1968) states that individual incentives lead to the overuse of common pool resources (CPRs) which in turn may have detrimental future consequences that affect everyone involved negatively. However, in many real-life situations this outcome does not occur and researchers such as Nobel laureate Elinor Ostrom suggested that mutual restraint by individuals can be the preventing factor. In mean field games (MFGs), since individuals are insignificant and fully non-cooperative, the TOTC is inevitable. This indicates that MFG models should incorporate a mixture of selfishness and altruism to capture real-life situations that involve CPRs. Motivated by this, we explore different equilibrium notions to capture a blend of cooperative and non-cooperative behavior in the population. First, we introduce mixed individual MFGs and mixed population MFGs where we also include the CPRs. The former captures altruistic tendencies at the individual level, while the latter models a population that is a mixture of fully cooperative and non-cooperative individuals. For both cases, we briefly discuss the definitions and characterization of equilibrium using forward-backward stochastic differential equations. Later, we present a real-life inspired example of fishers where the fish stock serves as the CPR. We analyze the existence and uniqueness results and discuss the experimental findings.

(Joint work with Mathieu Lauriere.)

Dynamic Games and Applications Seminar

Properties of guaranteed cost equilibrium in scalar infinite horizon linear quadratic differential games

Oct 30, 2025 11:00 AM — 12:00 PM (Montreal time)

Zoom webinar link

We consider infinite-horizon linear-quadratic differential games (LQDGs) with a state-feedback information structure and guaranteed cost equilibrium (GCE) as the solution concept. Once the players reach a GCE, no player has an incentive to deviate from the equilibrium strategy, as each has achieved a desired upper bound on her cost. In this work, we provide conditions for the existence of a GCE in scalar LQDGs and investigate the related welfare properties. Furthermore, we specialize these results to symmetric and two-player scenarios.

(with Aniruddha Roy)

Dynamic Games and Applications Seminar

Evolutionary Dynamics of Costly Signaling

Oct 16, 2025   11:00 AM — 12:00 PM (Montreal time)

Zoom webinar link

In this talk, I give an overview of three recent works joint with Josef Hofbauer on the evolutionary dynamics of costly signaling in three larger classes of games:

games in which the costly signal imposes a cost also on the receiver in case they accept to engage with the sender in the social exchange at stake (hiring, buying, mating). Examples of this last scenario are: agency commissions at conclusion of a contract, sickness presenteeism (attending work while sick), and politeness in language.

classical costly-signaling games à la Spence (education as a costly signal in the job market) and Zahavi (display of ‘handicaps’ in mating, stotting, coloration of autumn leaves), as investigated in Hofbauer and Pawlowitsch (2025 IJGT),

games in which players get a positive payoff increment when producing a signal (Hofbauer and Pawlowitsch 2025, Dynamic Games and Applications), and,