Influence of committed volunteers on helping behavior in emergency evacuations

We study how the presence of committed volunteers influences the collective helping behavior in emergency evacuation scenarios. In this study, committed volunteers do not change their decision to help injured persons, implying that other evacuees may adapt their helping behavior through strategic interactions. An evolutionary game theoretic model is developed which is then coupled to a pedestrian movement model to examine the collective helping behavior in evacuations. By systematically controlling the number of committed volunteers and payoff parameters, we have characterized and summarized various collective helping behaviors in phase diagrams. From our numerical simulations, we observe that the existence of committed volunteers can promote cooperation but adding additional committed volunteers is effective only above a minimum number of committed volunteers. This study also highlights that the evolution of collective helping behavior is strongly affected by the evacuation process.

STRATEGIC INTERACTIONS AND NEGATIVE OIL PRICES

This paper argues on theoretical grounds that the negative oil prices event on April 20, 2020, was mainly due to the strategic interactions among some active traders on both sides of the futures contract. We present a three-player game of futures trading in which a continuum range of negative price can be supported as (strong) Nash equilibrium, yet none of those constitutes an [Formula: see text]-equilibrium originally developed by Ma (2009). We further propose the notion of coalition-with-side-payment as a solution concept for the environment where strategic interactions and transfer payments among players are allowed. Our model captures the mechanism underlying futures price manipulation, and its predictions largely agree with the observations on that day, which are beyond the scope of demand–supply and physical delivery narratives.

The Stackelberg Games of Water Extraction with Myopic Agents

We consider a discrete-time, infinite-horizon dynamic game of groundwater extraction. A Water Agency charges an extraction cost to water users and controls the marginal extraction cost so that it depends not only on the level of groundwater but also on total water extraction (through a parameter [Formula: see text] that represents the degree of strategic interactions between water users) and on rainfall (through parameter [Formula: see text]). The water users are selfish and myopic, and the goal of the agency is to give them incentives so as to improve their total discounted welfare. We look at this problem in several situations. In the first situation, the parameters [Formula: see text] and [Formula: see text] are considered to be fixed over time. The first result shows that when the Water Agency is patient (the discount factor tends to 1), the optimal marginal extraction cost asks for strategic interactions between agents. The contrary holds for a discount factor near 0. In a second situation, we look at the dynamic Stackelberg game where the Agency decides at each time what cost parameter they must announce. We study theoretically and numerically the solution to this problem. Simulations illustrate the possibility that threshold policies are good candidates for optimal policies.

Strategic Interactions and Uncertainty in Decisions to Curb Greenhouse Gas Emissions

This paper examines the strategic interactions of two large regions making choices about greenhouse gas emissions in the face of rising global temperatures. Three central features are highlighted: uncertainty, the incentive for free riding, and asymmetric characteristics of decision makers. Optimal decisions are modelled in a fully dynamic, feedback Stackelberg pollution game. Global average temperature is modelled as a mean reverting stochastic process. A numerical solution of a coupled system of Hamilton-Jacobi-Bellman equations is implemented and the probability distribution of outcomes is illustrated with Monte Carlo simulation. When players are identical, the outcome of the game is much worse than the social planner’s outcome. An increase in temperature volatility reduces player utility, making cooperative action through a social planner more urgent. Asymmetric damages or asymmetric preferences for emissions reductions are shown to have important effffects on the strategic interactions of players.

Coping with Digital Extortion: An Experimental Study of Benefit Appeals and Normative Appeals

Digital extortion has emerged as a significant threat to organizations that rely on information technologies for their operations. Using human subject experimentation, we study the effectiveness of message appeals in encouraging defenders to adopt two mitigation strategies, investment in security and refusal to pay ransoms, to digital extortion threats. We explore two types of appeals, benefit and normative, for this purpose. We find that the decisions of the defenders (representing any organization that can be a potential victim) deviate from the predictions of game theory. However, given the strategic interactions between the defenders and the attacker as well as noisy decision-making behaviors, it is challenging to untangle the influence of the appeals on the defenders. We develop a structural model based on the quantal response equilibrium framework to measure how message appeals change the defenders’ utilities of investment and payment refusal. Although the interventions may be successful in increasing the utilities of investment and/or payment refusal, their impacts on investment rate and payment rate are mitigated by the attacker reducing ransoms. Thus, it is challenging for an intervention to significantly boost a community’s investment rate or to suppress the ransom payment rate. We characterize how security outcomes of a community (including expected ransom, attack rate, investment rate, and payment rate) vary with the defenders’ utilities of investment and pay refusal. This paper was accepted by Chris Forman, information systems.

Financial Reporting, Auditing, Analyst Scrutiny, and Investment Efficiency

This paper presents an economic framework to study strategic interactions along the analyst-auditor-owner disciplinary chain, in which the auditor examines the financial reports prepared by the owner, and the analyst uncovers financial misreporting as well as audit failure. We find that although analyst scrutiny ex post detects misreporting, it ex ante aggravates the owner's misreporting behavior and further impairs financial statement reliability if the legal penalties for the auditor and the owner are small. We also show how the effects of a regulation depend on its target's disciplinarian(s). Specifically, (i) although enhancing the auditor's legal liability always increases audit quality and financial statement reliability, it decreases investment efficiency if and only if the analyst is highly independent; and (ii) increasing the owner's misreporting penalty decreases investment efficiency if and only if either of (but not both) the regulations on the auditor and the analyst is strict.