International Society of Dynamic Games

Dynamic Games and Applications Seminar

Impacts of Different Contracts and Policy Constraints in a Distributional Robust Approach

February 8, 2024 11:00 AM — 12:00 PM (Montreal time)

Zoom webinar link

This research tackles decentralized supply channels and proposes comprehensive solution algorithms for multi-periodic bilevel equilibrium problems. The supply channel consists of two members, an upstream member (manufacturer) and a downstream member (retailer), who assume the roles of leader and follower, respectively, in a Stackelberg game. The primary objective of the channel is to effectively manage dynamic demand, which is dependent on price history, within a multi-period time frame. Due to the price history effect on the uncertain demand, the problem turns out to be highly nested. We present a channel facing dynamic and price-dependent demand, where the demand information is incomplete, and the only information provided is the mean and the standard deviation of the demand. To address this challenge, a distributional-robust (DR) approach is proposed, which provides a lower bound on the channel’s expected profit for the problem with known distribution. We consider both periodic contracts (a subgame perfect solution) and single contract (covering all periods simultaneously). The leader’s expected payoff of a single contract, logically, is not lower than the subgame perfect result. For the follower on the other hand, we did not observe any counterexample to demonstrate that he may be worse off by using a single contract. The algorithm optimally addresses concerns related to corrective actions. It incorporates pollution capacity constraints, pollution tax, and a cap-and-trade system. Moreover, a buyback contract influence, to share the risk of leftovers optimally, is evaluated. (joint work with Leif Kristoffer Sandal)

Dynamic Games and Applications Seminar

Insurance choices and emission taxation

February 1, 2024 11:00 AM — 12:00 PM (Montreal time)

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We analyze a duopoly composed of a clean and a dirty firm. The dirty one has to pay an emission tax. Both firms face a random loss that is a function of the dirty firm’s output. The firms can reduce the risk by stipulating an insurance contract and choosing a coinsurance rate. The game develops in three stages: 1) strategy selection, 2) output choices, 3) insurance decisions. We find that not only taxation but also insurance, under some conditions, can favor a green transition.

Dynamic Games and Applications Seminar

Multiplex networks: stability and opinion dynamics

January 25, 2024 11:00 AM — 12:00 PM (Montreal time)

Zoom webinar link

Interactions among agents or players in the society are usually performed in several layers, therefore, regular one-layer networks cannot properly describe the processes that can be observed in real-world networks. We examine the stability of multiplex networks when players interact in different layers and can reduce their costs of communication by creating connections with the same players in many layers. Then we examine how opinions are distributed in two-layer networks. We propose a general concealed voter model (GCVM), in which individuals interact in two layers and can exchange their opinions in the internal layer. By exchanging opinions in the internal layer, we mean that individuals share their real or internal opinions with their close friends. The process of opinion formation in GCVM is presented in the paper. We make a series of numerical simulations of GCVM with different network structures (both external and internal) and get some counterintuitive conclusions. 

(Joint work with Ziyu Ma and Chi Zhao)