Samaritan versus rotten kid: another look

We set up a two-stage game with sequential moves by one altruist and n selfish agents. The Samaritan's dilemma (rotten kid theorem) states that the altruist can only reach her first best when the selfish agents move after (before) the altruist. We find that in general, the altruist can reach her first best when she moves first if and only if a selfish agent's action marginally affects only his own payoff. The altruist can reach her first best when she moves last if and only if a selfish agent cannot manipulate the price of his own payoff

Liberalizing Trade in Environmental Goods

Trade liberalization in environmental goods is high on the agenda of the current Doha round. We examine its effects in a model with one domestic downstream polluting firm and two upstream firms (one domestic, one foreign). The domestic government sets the emission tax rate after the outcome of R&D is known. The upstream firms offer their technologies to the downstream firm at a flat fee. The effect of liberalization on the domestic upstream firm's R&D incentive is ambiguous. Liberalization usually results in cleaner production, which allows the country to reach higher welfare. However this increase in welfare is typically achieved at the expense of the environment (a backfire effect). Thus our results cast doubt on the hoped-for "win-win-win" outcome of trade liberalization in environmental goods.Pollution abatement technology, R&D, trade and environment, trade liberalization, backfire effect

Group rewards and individual sanctions in environmental policy

We examine an incentive scheme for a group of agents, where all agents are rewarded if the group meets its target. If the group does not meet its target, only the agents that meet their individual target are rewarded. In environmental policy, the EU burden sharing agreement and the UK Climate Change Agreements feature this incentive scheme. There is only a difference in outcome between group and individual rewards if emissions are stochastic. Group rewards generally lead to higher expected emissions than individual rewards. The attraction of the group reward scheme may lie in its fairness and its tough-looking targets.Team incentive scheme, stochastic pollution, UK Climate Change Agreements

Permit Trading and Credit Trading: A Comparison of Cap-Based and Rate-Based Emissions Trading under Perfect and Imperfect Competition

This paper compares emissions trading based on a cap on total emissions (permit trading) and on relative standards per unit of output (credit trading). Two types of market structure are considered: perfect competition and Cournot oligopoly. The e?ect of combining the two schemes is also discussed. We ?nd that output and abatement costs are higher under credit trading. Combining the two schemes may give an increase in welfare. With perfect competition, permit trading always leads to higher welfare than credit trading. With imperfect competition, credit trading may out perform permit trading. Environmental policy can lead to both entry and exit of ?rms. Entry and exit have a profound impact on the performance of the schemes, especially under imperfect competition. We ?nd that it may be impossible to implement certain levels of total industry emissions. Under credit trading several levels of the relative standard can achieve the same total level of emissions.emissions trading, entry and exit, permit allocation, tradable performance standards

Group Rewards and Individual Sanctions in Environmental Policy

We examine an incentive scheme for a group of agents, where all agents are rewarded if the group meets its target. If the group does not meet its target, only the agents that meet their individual target are rewarded. In environmental policy, the EU burden sharing agreement and the UK Climate Change Agreements feature this incentive scheme. There is only a difference in outcome between group and individual rewards if emissions are stochastic. Group rewards generally lead to higher expected emissions than individual rewards. The attraction of the group reward scheme may lie in its fairness and its tough-looking targets.Team Incentive Scheme, Stochastic Pollution, UK Climate Change Agreements

Partial International Emission Trading

In a model inspired by the EU Emissions Trading Scheme, non-cooperative countries allocate their emissions to internationally trading and non-trading sectors. Each country is better off with trading than without, and aggregate welfare is maximized with all sectors in the trading scheme. We simulate the effects of expanding the trading scheme in a two-country model with quadratic abatement costs. If only the original trading sector is asymmetric between countries, the welfare change is always positive and the same in both countries. If only the additional trading sector is asymmetric, one country might lose, but there is an aggregate welfare gain. If only the non-trading sector is asymmetric, both countries always gain.International emission trading; EU Emission Trading Scheme

Payments from Households to Distant Polluting Firms

We investigate a novel way to encourage separation between firms, causing local pollution, and their victims (households): payments from households to distant polluting firms. These payments do not require monitoring of firms’ emissions or their abatement costs. In our model, households and firms can choose from two locations (A and B, with A larger than B). Households incur environmental damage from firms in the same location. Under laissez faire, payments from households in one location (say A) to firms in the other location (say B) will prompt firms to move from A to B and to stay there, thus reducing damage to households in A. The maximum that households are willing to pay temporarily is the amount that currently makes them indifferent between A and B. The payments make A less attractive to firms as well as to households. The unique positive-payment equilibrium implements the global welfare optimum where laissez faire does not. We examine from which starting points this payment equilibrium can be reached

Emissions Trading and Intersectoral Dynamics: Absolute versus Relative Design Schemes

This paper examines the interdependence between imperfect competition and emis- sions trading in a two-sector (clean and dirty) economy. We compare the welfare implica- tions of an absolute cap-and-trade scheme (permit trading) with a relative intensity-based scheme (credit trading). We nd unambiguously more clean rms in the long run under credit trading. However, neither emissions trading con guration creates the rst-best out- come: there are too few (many) clean rms under permit (credit) trading. Permit trading dominates credit trading in terms of overall welfare at the long run equilibrium, except when policy is relatively lenient. It is also demonstrated that stricter policy does not necessarily induce the clean sector to grow relative to the dirty sector and we determine under what conditions this holds

Pareto-Efficient Solutions for Shared Public Good Provision: Nash Bargaining versus Exchange-Matching-Lindahl

We compare two cooperation mechanisms for consumer/producers of a public good: the Nash Bargaining Solution (NBS) and the Exchange-Matching-Lindahl (EML) solution, where each agent specifies her demand for and supply of the public good according to her personal exchange rate. Both mechanisms are Pareto-efficient. EML is equivalent to matching. In our specific model with linear or quadratic benefits and quadratic costs, EML and NBS are equivalent when there are two agents. With more than two agents, the high-benefit/low-cost agents are better off under EML. We also analyze outsourcing, where agent i can pay agent j to produce the amount that agent i promised to contribute. In our specific model, payments from high-cost to low-cost agents (and from high-benefit to low-benefit agents) are (usually) lower in EML than in NBS

Multiple-aggregate games

Consider an environment in which individuals are organised into groups, they contribute to the collective action of their group, and are influenced by the collective actions of other groups; there are externalities between groups that are transmitted through the aggregation of groups' actions. The theory of 'aggregative games' has been successfully applied to study games in which players' payoffs depend only on their own strategy and a single aggregation of all players' strategies, but the setting just described features multiple aggregations of actions---one for each group---in which the nature of the intra-group strategic interaction may be very different to the inter-group strategic interaction. The aim of this contribution is to establish a framework within which to consider such `multiple aggregate games'; present a method to analyse the existence and properties of Nash equilibria; and to discuss some applications of the theory to demonstrate how useful the technique is for analysing strategic interactions involving individuals in groups