This chapter describes an incentive-based market that integrates the economic layer and the physical layer to guarantee high-quality physical ancillary services in dynamic power networks. Toward the full liberalization of the electricity markets, it is indispensable to develop a socially optimal regulation market with a high-speed market-clearing mechanism while preventing maliciously strategic biddings of market participants called agents. To realize the markets, the utility functioning as a system operator prepares an appropriate incentive mechanism to elicit the agents’ private information. We refer to this real-time incentive-enabled market as an incentivizing market. After illustrating the issues of the agents’ strategic biddings without incentive mechanisms, we mainly propose incentivizing market mechanisms for moral hazard problems and adverse selection problems in dynamic power networks, respectively. We also discuss features, possibilities, and limitations of our proposed mechanisms through simulations for linear quadratic Gaussian (LQG) power networks.

© 2016 Society for Environmental Economics and Policy Studies and Springer JapanThe Home Appliance Eco-Point System was a subsidy program implemented by the Japanese government from May 2009 to March 2011. The system has two features. First, the subsidy was provided in the form of eco-points that were only exchangeable for environmentally friendly goods. Second, it was a replacement subsidy program for durable goods with uncertain termination dates. We investigate the policy implications of these features. We show that if the eco-points are exchangeable for any goods (i.e., if a simple rebate program rather than an eco-point system is implemented), the same outcome can be achieved at a lower subsidy rate and thus using fewer financial resources. Regarding the eco-point system as a replacement subsidy, we show that the uncertain termination has the same effect as an increase in the subsidy: both accelerate the replacement. Uncertainty is a substitute for a subsidy, thus saving the financial resources of the government. However, there are two welfare concerns: (a) acceleration may not be desirable in terms of the environment, and (b) it costs households their expected utility.

In recent decades, climate change and resource limitations have become serious problems. To overcome these problems, many countries promote the introduction of renewable energy. However, the diffusion of renewable energy requires a novel supply and demand system for electricity. One remarkable method of controlling electricity demand is a demand-side control based on dynamic pricing. This study analyzes electricity consumption behavior using laboratory experiments. In particular, the authors focus on the effect of supply limitations on consumption behavior. The results of the experiment include significant findings that help provide an understanding of electricity consumption behavior. More specifically, the announcement of a supply limitation affects the decision to consume electricity. Results of this study indicate that cooperative people tend to decrease electricity consumption more when they are aware of the possibility of an electrical outage. This finding implies that researchers need a better understanding of the psychological aspects of electricity consumption behavior. (C) 2016 American Society of Civil Engineers.

<p>本稿では，長期的な環境問題を念頭に，割引率に関する様々な議論を紹介する．まず，Frank Ramsey の古典的な研究を出発点に，世代間衡平性との兼ね合いから割引の問題を論ずる．また，主に不確実性に焦点を当てながら，DDR と呼ばれる比較的新しい割引理論について詳細に解説する．さらに，割引率が費用便益分析の中で果たす役割についても，地球温暖化問題を例に具体的に示す．</p>

Economists have argued about various discount rates. Strotz (1955-56) first suggested that there is no reason to consider a time-consistent discount rate such as an exponential function. Over the past five decades, various functional theoretical forms have been proposed, including exponential, hyperbolic, and quasi-hyperbolic. Simultaneously, empirical studies have found there is a possibility that observed discount rates are not constant over time. The data tend to not fit exponential functional forms but rather hyperbolic ones; this implies declining discount rates. Furthermore, empirical studies have found that discount rates vary across objects. Fredrick et al. (2002) summarized the annual discount rates found in previous empirical studies. Table 23.1 summarizes annual discount rates estimated in previous literature. The literature suggests various annual discount rates, and the results depend on the type of goods, the time range, and/or the estimation methods. In this chapter, we consider the discount rates on environmental values, and especially on long-term problems, as these are not empirically addressed in previous literature.

We show that in poor resource-based communities, the socio-psychological preference for employment, which arises from a strong desire to follow the communal norm of sharing in harvesting efforts, can lead to the optimality of full-employment harvesting until resource extinction. We show that such communities may be able to sustain both their natural resources and full employment by using outside-the-community employment opportunities or by economic diversification. However, to be effective, such policies must ensure that the outside wage rate and the initial capital stock are above certain minimum levels which depend on the existing size of the resource stock, the characteristics of the community’s harvesting technology, and the biological growth characteristics of the resource in question, and which will be higher the longer the remedial policies are delayed.

This paper defines a sustainable development path as a balanced growth path with environmental conservation. In the framework of endogenous growth theory, it is known that a sustainable development path is optimal only if the following three conditions are satisfied: (1) the engine of economic growth is clean
(2) the assimilation capacity of the environment is high enough to endure the increasing environmental load with economic growth
and (3) the population has an egalitarian propensity with the elasticity of the marginal utility of consumption that is greater than or equal to one. While all of these three conditions are intuitively plausible, there are distinctions between the first two and the last one: the former can be obtained by our endeavors, whereas the latter concerns preference that is endowed rather than obtained. We show that this preference constraint can be relaxed if the production technology satisfies the condition that the elasticity of transformation to the production factor and the environmental service, after appropriate monotone transformation, is greater than one.

It is known that in an intertemporal competitive economy, a tradable permit system may not achieve efficiency without setting appropriate permit interest rates (i.e., rewards for holding permits). To find the rates, however, we need to know in advance the path of efficient permit prices, which is difficult to obtain. This study intends to solve this problem in two ways. First, we analyze a special case in which the permit interest rates are given by a simple rule. For example, if the marginal abatement cost of pollution emission is constant, then the appropriate rate is to equal the monetary interest rate. As is the case for global warming, if the damage is caused in the future far beyond the planning period of the environmental program, the appropriate rate coincides with the marginal self-recovery of environmental stock under certain conditions. As a second approach, we propose a tradable permit system with a permit bank, as a mechanism by which the permit interest rates are generated endogenously without governmental intervention other than the issuance of permits. However, we also show that this approach raises the problem of indeterminacy of the equilibrium.

We study the relation between dynamical systems describing the equilibrium behavior in dynamic games and those resulting from (single-player) dynamic optimization problems. More specifically, we derive conditions under which the dynamics generated by a model in one of these two classes can be rationalized by a model from the other class. We study this question under different assumptions about which fundamentals (e.g. technology, utility functions and time-preference) should be preserved by the rationalization. One interesting result is that rationalizing the equilibrium dynamics of a symmetric dynamic game by a dynamic optimization problem that preserves the technology and the utility function requires a higher degree of impatience compared to that of the players in the game.

This paper develops an optimum forest program for even-aged and multi-age forest management when the carbon sequestration service of a forest has value. It is shown that for even-aged forest management, the optimum rotation might be longer or shorter than when the carbon sequestration service is not considered. For multi-age forest management, it is shown that the optimum steady state is characterized by the optimum rotation for an even-aged forest. The optimum rotation is affected by how to evaluate the carbon release after harvesting, which is a central concern for the issue of "harvested wood products" in the United Nations Framework Convention on Climate Change. © 2011 Springer.

We show that the critical capital stock of the Dechert and Nishimura (1983) model is a decreasing and continuous function of the discount factor. We also show that the critical capital stock merges with a nonzero steady state as the discount factor decreases to a certain boundary value, and that the critical capital stock converges to the minimum sustainable capital stock as the discount factor increases to another boundary value. (C) 2011 Elsevier B.V. All rights reserved.

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This paper evaluates tax schemes in a class of differential games. The results indicate that there are many tax schemes that support efficient resource usage, but each may fail to implement the targeted resource because of the multiplicity of equilibria. Since all of the equilibria are subgame perfect, it is difficult to predict which specific one arises. Care must then be taken in using a tax scheme as a remedy for the "tragedy of the commons." The advantages of other policy instruments (including command-and-control regulation and a tradable permit system) are also discussed.

小特集 : 環境経済学の新展開(下)このノートでは, ダイナミック・ゲームの基礎的な事柄を述べるとともに, その環境経済学への応用について紹介する。天然資源や環境資産, 汚染ストックは広い意味での資本であり, それらの所有権は多くの場合に曖昧である。ダイナミック・ゲームは, このような財の利用を分析するのに適当な分析枠組みである。他方, 環境経済学は, ダイナミック・ゲーム理論の主要な応用分野になっている。This study, while discussing basic matters of dynamic games, introduces its application to environmental economics. In the context of natural resources and environmental assets, contaminated stock capital is, in a broad sense, capital, and its ownership is often obscure. A dynamic game is an appropriate analytical framework to analyze the use of such assets. On the other hand, the application of the dynamic game theory to environmental economics has become widespread.

Pollution from consumption and production is an inevitable part of economic processes. We employ a materials balance approach and develop an endogenous growth theory, with recycling activity, to examine the evolution of the economic and environment systems. This paper provides feasibility and optimality conditions for sustainable economic growth with rising environmental quality. The fundamental condition of feasibility is that the flow of natural resources, which eventually returns to the environment as waste and pollution, has a negative growth rate in the long run. (C)2007 Elsevier B.V. All rights reserved.

Exhaustion of a natural resource stock may be a rational choice for an individual and/or a community, even if a sustainable use for the resource is feasible and the resource users are farsighted and well informed on the ecosystem. We identify conditions under which it is optimal not to sustain resource use. These conditions concern the discounting of future benefits, instability of a social system or ecosystem, nonconvexity of natural growth function, socio-psychological value of employment, and strategic interaction among resource users. The identification of these conditions can help design policies to prevent unsustainable patterns of resource use.

This paper considers how environmental problems affect economic growth. In order to explain the relationship between the economy and the environment, we impose the law of mass conservation and its corollary, the mass balance principle, and consider pollution from both production and consumption sectors. Utilising a model which incorporates the material balance principle on endogenous growth theory, we obtain the following results. • Where environmental problems are not serious, optimal economic growth rates at a steady state rise as these problems become more severe. However, there is a threshold for the degree of their seriousness, beyond which the relationship is reversed, i.e., environmental problems lower optimal economic growth rates. • A similar relationship is found between the economic growth rates at social optimum and at a laissez-faire competitive equilibrium. The optimal growth rate is higher (lower) than the equilibrium growth rate if the degree of seriousness of environmental problems is below (above) a threshold. Copyright © 2006 Inderscience Enterprises Ltd.

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This paper considers the timing of timber harvesting under uncertainty. The decision of a forest manager who maximizes the expected utility is formalized using a form of the closed loop control model. The stochastic optimization problem derived is very similar to the deterministic single stand problem known as the classical Faustmann formula, but there is a notable difference. Whilst optimal rotation periods are certain in the deterministic world, they are random variables in stochastic circumstances. Stochastic optimal rotation periods are difficult to include in forest economic analyses. Fortunately, under some technical assumptions, we can find a non-stochastic variable named "barrier" which corresponds to the optimal cutting stock size in the deterministic world. This paper shows that the von Neumann-Morgenstern forest manager cuts his/her trees when the stochastic stumpage values reach a certain amount, that is the barrier. Comparative statics on the barrier were conducted to evaluate the effect of planting costs and the degree of the manager's risk aversion. The results show that the barrier rises as planting costs increase or as the Arrow-Pratt index of absolute risk aversion becomes smaller.

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本論文では,ヘドニック法を用いて森林の生活環境価値を計測した。宅地価格に注目したヘドニック式の勾配ベクトルは,ある条件の下で,人々の生活環境特性に対する限界支払意志額として解釈できる。したがって森林に関するその値は,森林の生活環境価値を表す。計測には,二次形式のヘドニック式を用いた。得られたヘドニック式は,期待された符号条件をほぼ満たした。この推定式を用いて,実際にある地域の森林の生活環境価値を推定した。結果として,森林の生活環境価値は,木材生産に基づく評価額よりもはるかに大きい一方で,森林が宅地に転用されるときの評価額とはあまり変わらない。本論文はまた,ヘドニック法の問題点も指摘した。引っ越しに要する費用が存在すると,ヘドニック価格(競争均衡価格)の非決定性が生じることを示した。また,人々の将来に対する予想が通常の推定では考慮されていないことも指摘した。結論として,ヘドニック法の利用に際して,得られた結果の解釈とその利用は,慎重にされねばならない。

本論文は以前の報告における想定をより現実的なものに変更して、分収造林契約の特質を森林資源の効率的利用の観点から検討した。ここで考察の対象となる分収造林契約とは造林地所有者と造林者を契約当事者とするものであり、また造林者を公的機関と見なしている。本論文で分析されたのは次の二つの場合である。1)林地所有者が用いる割引率よりも公的機関が用いる割引率が小さい場合。2)森林の外部性が存在する場合。以前の結果とは異なり、いずれの場合においても契約が行われる伐期齢と分収率は一意的ではなくなる。しかし、依然として、社会的に最適な伐期齢での契約は可能である。また森林の外部性が存在する場合、公的機関が分収造林契約によって得られる便益を最大にするように行動することは森林資源の効率的利用とは一致しないことを明らかにした。結論として公的機関が社会的最適伐期齢での契約を林地所有者に提示する限り、分収造林契約は森林資源の効率的利用を実現するための一つの有効な政策手段となる。したがって造林者としての公的機関の役割は重要である。

成長する森林をいつ伐採すべきかという問題に対する諸経済モデルの集まりを, ここでは最適伐期齢理論と呼ぶ。最適伐期齢理論は森林所有者及び林業経営者に関する主体均衡モデルであり, ミクロ経済学的接近によって森林・林業の経済分析を行なう上での, 基礎理論となるものである。本論文は, この最適伐期齢理論の発展を概観し, 今後の理論的課題を明らかにしようとするものである。最適伐期齢理論は, ミクロ経済学における投資の理論や資本の理論の発展にともなって, その内容を豊かにしてきている。その理論は, 決定論的定常性下における単一一斉林分のl点投入l点産出モデルとして, これを定式化することから始まった。ただし, 1950年代のミクロ経済学の導入期にあっては, 最適伐期齢の決定ルールについて少なからぬ混乱があった。それは, 費用の概念についての誤った認識によるものである。今日では, 理論的に最も適切な決定ルールは, 無限の将来にわたって林地から得られる利潤の流列の現在割引価値を最大にするファウストマン式であることが知られている。このファウストマン式の比較静学分析, つまり, 木材価格や利子率などの変化が最適伐期齢と林地価値に及ぼす影響は, 今日までに十分検討されている。また, ファウストマン式をさらに現実の世界における伐期選択問題に近づけるための試みが行なわれている。その一つは, 1点投入l点産出の仮定に関するものであり, 制御理論を応用した最適間伐方策の定式化がみられる。また, 定常性の仮定を緩めて木材価格などの変化を許すモデルが発表されている。木材価格の変化を仮定したモデルでは, 最適伐期齢決定問題は等号制約条件付最適化問題に帰着する。林業投資は不確実な将来に対する意思決定であり, またそれは非常に長期的な時間視野のもとに行なわれる。この点からすれば, ファウストマン式の拡張において最も重要なものは, 不確実性下におけるモデルの再定式化である。しかも, 林業, 森林の特質を考えると, それは多段階の意思決定問題として定式化される必要がある。現在, 危険中立者の仮定の下でこのようなモデルがいくつか発表されている。ただし, 現実の多くの経済主体は危険回避者として行動すると考えられ, 最適伐期齢理論をより現実に近づけるためには, 危険回避者を前提としたモデルが求められている。しかし, 多段階の逐次決定モデルとして, この要望を満たすモデルは未だなく, この点が最適伐期齢理論の課題と言える。