In evaluating environmental policy, researchers have tended to focus on the industry or market that is targeted by regulation and to disregard policy impacts in other parts of the economy. Recent research indicates, however, that in economies where governments rely on distortionary taxes, environmental regulation can profoundly affect costs and efficiency in areas other than the targeted industry or market. These findings signal the importance of evaluating environmental policy using a general equilibrium framework - an approach that can capture interactions across industries, sectors or markets. General equilibrium analysis can fundamentally alter the evaluation of environmental tax policies, and can overturn conventional wisdom concerning the relative cost-effectiveness of environmental taxes, emissions quotas, or mandated technologies.This volume gathers together important papers on the general equilibrium impacts of environmental regulation in the presence of distortionary taxes. Topics include optimal environmental taxation,'green tax reform' and the 'double dividend', and the choice among alternative policy instruments. The volume will be of interest to environmental economists, public finance economists and researchers interested in the economics of regulation.

The earth, our home, is in crisis. There are two sides to this crisis-our global economy, and its effect on the ecology of our home planet. Despite conventional thinking that typical monetary and fiscal manipulations will put us back on the path of economic growth, the reality is not that simple. Meanwhile, the natural environment is sending unmistakable warnings. Glaciers are melting; oceans are becoming dangerously acidic; species and their ecological services are becoming extinct; and weather patterns are becoming increasingly severe and unpredictable each year. The stress on resource systems of all kinds threatens to shrink the carrying capacity of the planet, even as we call upon it for increased contributions to support a burgeoning human population. Co-written by an ecologist and an economist, Economics and Ecology: United for a Sustainable World counsels the replacement of symptomatic thinking with a systemic worldview that treats the environment and the economy as an ecosystemic unit. The first part of the book establishes the methodological and biophysical principles needed to develop the concept of socioeconomic sustainability. The second part of the book examines the misuse of economics in the service of what increasingly appears to be a ruinous pursuit of material wealth and expansion. The third part offers advice on reconciling economics and ecology by proposing an economics in which the principles employed are aligned with the biophysical principles of ecology. This timely volume puts forth a sustainable worldview based on systemic thinking, with the emphasis more on what and how people think than on what they do. A unique reference for professionals and laypersons alike, it can also serve as a supplementary classroom text for students of economics, ecology, biology, and environmental science.

With different intensities, depending on the season, every morning and evening of any weekday there are the same peaks in electricity demand. Peaks can bring about significantly negative environmental and economic impacts. Demand Side Response is a relatively recent solution in Europe which has the potential to reduce peak demand and ease impending capacity shortages. Peak Energy Demand and Demand Side Response presents evidence on a set of Demand Side Response activities, ranging from price-based to incentive-based programmes and policies. Examples are drawn from different programmes for both residential and non-residential sectors of electricity demand, including Time of Use tariffs, Critical Peak Pricing Automated Demand Controllers and Ancillary Services. The book also looks at the actual energy saving impacts of smart meters, the activities which constitute peak demand and the potential opportunities associated with European smart grids and Capacity Markets. This is the first book presenting comprehensive analysis of the impacts, cost benefits and risks associated with Demand Side Response programmes and policies. It should be of interest to students, scholars and policy-makers in the areas of energy, environmental economics and applied economics.

This original contribution to the field is the first to bring economic sociology theory to the study of federal land exchanges. By blending public choice theory with engaging case studies that contextualize the tactics used by land developers, this book uses economic sociology to help challenge the under-valuation of federal lands in political decisions. The empirically-based, scholarly analysis of federal-private land swaps exposes serious institutional dysfunctions, which sometimes amount to outright corruption. By evaluating investigative reports of each federal agency case study, the book illustrates the institutional nature of the actors in land swaps and, in particular, the history of U.S. agencies' promotion of private interests in land exchanges. Using public choice theory to make sense of the privatization of public lands, the book looks in close detail at the federal policies of the Bureau of Land Management and the U.S. Forest Service land swaps in America. These pertinent case studies illustrate the trends to transfer federal lands notwithstanding their flawed value appraisals or interpretation of public interest; thus, violating both the principles of equality in value and observance of specific public policy. The book should be of interest to students and scholars of public land and natural resource management, as well as political science, public policy and land law.

Non-market environmental valuation (NMEV) is undergoing a period of increased growth in both application and development as a result of increasing recognition of the role of economics in environmental policy issues. Against this backdrop, The International Handbook on Non-Market Environmental Valuation brings together world leaders in the field to advance the development and application of NMEV as a tool for policy-making. The expert contributors provide insights into the state of the art across the spectrum of both revealed and stated preference methods and highlight new directions being taken. A sequence of topical applications demonstrate various techniques and illustrate what can be achieved using NMEV: deliberately diverse case studies are drawn from Europe, North America, Asia and Australia with valuation targets ranging across use and non-use values of the environment. A number of reviews of cutting-edge issues are also presented. This outstanding resource will enable those interested in environmental valuation from theoretical, practical or policy perspectives to bring themselves to the forefront of developments and practice. As such, this Handbook will prove invaluable to a wide-ranging audience encompassing academics, researchers, students, practitioners and consultants involved in environmental economics and NMEV.Contributors: S. Bain, I.J. Bateman, J. Bennett, E.Y. Besedin, M.C.J. Bliemer, R. Brouwer, R.T. Carson, J. Champ, J. Cheesman, S. Colombo, J. Downing, J. Englin, S. Garcia, M. Giergiczny, A. Gonzalez-Caban, T. Groves, N. Hanley, J.A. Herriges, S. Hess, T. Holmes, Y. Jeon, R.J. Johnston, H.A. Klaiber, C.L. Kling, Y. Liu, J. Loomis, P.-A. Mahieu, K.E. McConnell, S. Navrud, A. Pang, G.L. Poe, P. Riera, J. Rolfe, J.M. Rose, E.T. Schultz, K. Segerson, V.K. Smith, J. Strand, P.J. Thomassin, D. Tinch, P. van Beukering, C.A. Vossler, X. Wang

Society today faces a difficult contradiction: we know exactly how the physical limits of our planet are being reached and exactly why we cannot go on as we have before - and yet, collectively, we seem unable to reach crucial decisions for our future in a timely way. This book argues that our definition of prosperity, which we have long assimilated with the idea of material wealth, may be preventing us from imagining a future that meets essential human aspirations without straining our planet to the breaking point. In other words, redefining prosperity is a necessary and urgent task. This book is the fruit of a long debate among 15 scholars from diverse fields who worked together to bring the depth and nuance of their respective fields to questions that affect us all. The result is a rich, transdisciplinary work that illuminates the philosophical and historical origins of our current definition of prosperity; identifies the complex processes that gave rise to the problems we face today; elucidates the ways in which our contemporary environmental, social, nutritional, economic, political, and cultural crises are interconnected; and explores why a half-century of economic growth has neither increased life satisfaction in the West nor vanquished world poverty. Approaching these broad-ranging questions from the specific standpoints of their disciplines, each of the authors offers thoughts for the future, considering possible escape routes and proposing changes to the way we live, behave, and organise society and public action - changes that actually respond, in an equitable way, to our deepest aspirations. Ultimately, in laying the groundwork for a public debate on this subject, this book poses a question to its readers: what is your definition of prosperity, and what can be done to promote it?

Projecting win-win situations, new economic opportunities, green growth and innovative partnerships, the green economy discourse has quickly gained centre stage in international environmental governance and policymaking. Its underlying message is attractive and optimistic: if the market can become the tool for tackling climate change and other major ecological crises, the fight against these crises can also be the royal road to solving the problems of the market. But how 'green' is the green economy? And how social or democratic can it be? This book examines how the emergence of this new discourse has fundamentally modified the terms of the environmental debate. Interpreting the rise of green economy discourse as an attempt to re-invent capitalism, it unravels the different dimensions of the green economy and its limits: from pricing carbon to emissions trading, from sustainable consumption to technological innovation. The book uses the innovative concept of post-politics to provide a critical perspective on the way green economy discourse represents nature and society (and their interaction) and forecloses the imagination of alternative socio-ecological possibilities. As a way of repoliticising the debate, the book advocates the construction of new political faultlines based on the demands for climate justice and democratic commons. This book will be of interest to students and scholars of environmental politics, political ecology, human geography, human ecology, political theory, philosophy and political economy. Includes a foreword written by Erik Swyngedouw (Professor of Geography, Manchester University).

K. William Kapp's heterodox theory of social costs proposes precautionary planning to pre-empt social costs and provide social benefits via socio-ecological safety standards that guarantee the gratification of basic human needs. Based on arguments from Thorstein Veblen, Karl Marx, and Max Weber, social costs are conceptualized as systemic and large-scale damages caused by markets. Kapp refutes neoclassical solutions, such as bargaining, taxation, and tort law, unmasking them as ineffective, inefficient, inconsistent, and too market-obedient. The chapters of this book present the social costs of markets and neoclassical economics, the social benefits of environmental controls, development planning, and the governance of science and technological standards. This book demonstrates the fruitfulness of the heterodox theory of social costs as a coherent framework to develop effective remedies for today's urgent socio-ecological crises. This volume is suitable for readers at all levels who are interested in the theory of social costs, heterodox economics, and the history of economic thought.

When we look at the state of the world today, what is most evident is the fact that the major problems of our time - energy, environment, economy, climate change and social justice - cannot be understood in isolation. They are interconnected problems, which means that they require corresponding systemic solutions. Today's global economy has brought about critical distress for ecosystems and societies and we have to go to the very root of the problems to find a way out. This volume develops a synthesized interpretation of ecological economics integrating different levels: (economic) system, (business) practice and the (economic) actor. It discusses how changes on a systems level are connected to changes in practice and development of individual consciousness. Transformative Ecological Economics delves into the insight and knowledge from different sources of inspiration (thermodynamics, Darwinism, anthroposophy and Buddhism) as well as into an integrated story describing and illustrating the core ideas, principles and values that characterize a utopian society anchored in ecological economics. Implementation of the deep changes demanded depends on our ability to write a new story, a utopian one for sure, but one which is in accordance with and based on the reality in which we live. This book will be of interest to those who study ecological economics, political economy and environmental economics.

The relationship between environmentally sustainable development and company and business law has emerged in recent years as a matter of major concern for many scholars, policy-makers, businesses and nongovernmental organisations. This book offers a conceptual analysis of the principles of sustainable development and environmental integration in the EU legal system. It particularly focuses on Article 11 of the Treaty on the Functioning of the European Union (TFEU), which states that EU activities must integrate environmental protection requirements and emphasise the promotion of sustainable development. The book gives an overview of the role played by the environmental integration principle in EU law, both at the level of European legislation and at the level of Member State practice. Contributors to the volume identify and analyse the main legal issues related to the importance of Article 11 TFEU in various policy areas of EU law affecting European businesses, such as company law, insurance and state aid. In drawing together these strands the book sets out the requirements of environmental integration and examines its impact on the regulation of business in the EU. The book will be of great use and interest to students and researchers of business law, environment law, and EU law.

Since becoming formally established with an international academic society in the late 1980s, ecological economics has advanced understanding of the interactions between social and biophysical reality. It initially combined questioning of the basis of mainstream economics with a concern for environmental degradation and limits to growth, but has now advanced well beyond critique into theoretical, analytical and policy alternatives. Social ecological economics and transformation to an alternative future now form core ideas in an interdisciplinary approach combining insights from a range of disciplines including heterodox economics, political ecology, sociology, political science, social psychology, applied philosophy, environmental ethics and a range of natural sciences. This handbook, edited by a leading figure in the field, demonstrates the dynamism of ecological economics in a wide-ranging collection of state-of-the-art essays. Containing contributions from an array of international researchers who are pushing the boundaries of the field, the Routledge Handbook of Ecological Economics showcases the diversity of the field and points the way forward. A critical analytical perspective is combined with realism about how economic systems operate and their essential connection to the natural world and society. This provides a rich understanding of how biophysical reality relates to and integrates with social reality. Chapters provide succinct overviews of the literature covering a range of subject areas including: heterodox thought on the environment; society, power and politics, markets and consumption; value and ethics; science and society; methods for evaluation and policy analysis; policy challenges; and the future post-growth society. The rich contents dispel the myth of there being no alternatives to current economic thought and the political economy it supports. The Routledge Handbook of Ecological Economics provides a guide to the literature on ecological economics in an informative and easily accessible form. It is essential reading for those interested in exploring and understanding the interactions between the social, ecological and economic and is an important resource for those interested in fields such as: human ecology, political ecology, environmental politics, human geography, environmental management, environmental evaluation, future and transition studies, environmental policy, development studies and heterodox economics.

Can trade liberalization and environmental protection be pursued together, or do the two objectives inevitably conflict? The rapid evolution of international regimes and institutions is increasingly bringing such conflicts to the fore. A consensus, both on the extent of the clash, and on how it can be resolved, does not yet exist. This volume includes the proceedings from the RIIA's April 1997 conference on trade and the environment, which brought together prominent contributors from all sides of the debate, including industry, governments, academics, NG0s and intergovernmental institutions such as the World Trade Organization, UNEP, UNCTAD and the OECD. They examine the background to the issue; the impacts of trade-related environmental measures; the relationship between environmental policy, competitiveness and investment; industry and developing country concerns; and the evolution of dispute settlement procedures in the EU and the WTO. The concluding chapter features a wide-ranging discussion on the future of the debate and of the WTO's Committee on Trade and Environment.

The current value of global trade has reached a staggering annual figure of $6 trillion in merchandise crossing borders. Such prolific global trading has, at the same time, begun to raise fears of pandemics and concerns for global health. Yet, investment in public health infrastructure and disease control was never designed to cope with international trade of this volume and diversity. Indeed, most health systems lag far behind, especially in poor countries. This has created new vulnerabilities for global populations to the introduction and amplification of infection through trade. Public fears have been further heightened by frightening news reports of deadly diseases such as Mad Cow disease and E. Coli. Risky Trade: Infectious Disease in the Era of Global Trade provides a thorough examination of the actual risks posed by disease in the age of globalization. Drawing on the economics of international trade and epidemiology, the author explores the critical health issues arising from the enormous increase in global trade and travel. Issues covered include: c The scale of the problem with particular reference to the Sakai outbreak of E. Coli; c Risks from particular microbes - Enteric and viral infections; Highly infectious agents; Antimicrobial resistance; and, Stealth agents; c Global outbreaks as a result of human travel and trade; c Prevention, surveillance and control; c The future health of global trading. In addition to highlighting the problems, the book also addresses some of the potential benefits the same globalization can bring to epidemic control through surveillance, diagnostics, treatment and investigation. The empirical approach ties together existing descriptions and case studies of epidemics building a comprehensive framework for examining new events and considering historical experience with infectious outbreaks. The volume will be a valuable guide to students, academics, practitioners, and policy makers in the areas of international trade, health economics, epidemiology, international/public health and disease control.

While biodiversity loss is an ecological phenomenon, it also has further dimensions - political, social and, last but not least, economic. From the economic perspective, the rapid loss of biological diversity can be viewed in two ways. First, the consequence of this deterioration process is a loss of options and an increase in scarcity of the environmental 'good', biodiversity. Second, economic activity and the structure of global and local economic institutions have frequently been identified as the major drivers of biodiversity loss. In economic terms, this constitutes a market failure - market-based economic activities lead to processes which undermine the long-term stability of these very activities. This book provides an ecological economic perspective on the value of diversity in ecosystems. Combining insights from various sub-disciplines of ecology and environmental/ecological economics, the author constructs a conceptual framework which identifies the ways in which biodiversity influences human well-being and offers a novel, unifying perspective on the economic value of biodiversity. This framework demonstrates that biodiversity's economic value mainly results from uncertainty about the future, regarding both supply of and demand for ecosystem services, and interconnections between ecosystems. The book goes on to identify suitable methods for economic valuation of biodiversity and discusses the currently underdeveloped and underused approach of deliberative monetary valuation. Combining a strong theoretical framework with practical examples, this book will be of great interest to students and researchers of ecological economics, ecosystem services, environmental values and environmental and resource economics.

'Inspiring. [...] Crammed with lively interviews and grounded examples' Ashish Kothari, founder of Kalpavriksh Permaculture is an environmental movement that makes us reevaluate what it means to be sustainable. Through innovative agriculture and settlement design, the movement creates new communities that are harmonious with nature. It has grown from humble origins on a farm in 1970s Australia and flourished into a worldwide movement that confronts industrial capitalism. The Politics of Permaculture is one of the first books to unpack the theory and practice of this social movement that looks to challenge the status quo. Drawing upon the rich seam of publications and online communities from the movement as well as extensive interviews with permaculture practitioners and organisations from around the world, Leahy explains the ways permaculture is understood and practiced in different contexts. In the face of extreme environmental degradation and catastrophic climate change, we urgently need a new way of living.

Originally published in 1990, this study tracks the issues, progress and problems in environmental issues in the United States from the 1980's. Improvements in air and water quality as well as regulation of hazardous waste and toxic substances has led to new policies such as the Superfund Act and a general increase in awareness about environmental issues on a federal level. Placing an emphasis on economics, these papers analyse the effectiveness of environmental policy and progress made in relation to air pollution, water quality, hazardous wastes, toxic substances and enforcement of regulations. This title will be of interest to students of environmental studies.

The authors of this in-depth study describe the theory and techniques that can be applied to the specific case of valuing potable water provided by groundwater supplies. The theory and techniques can be extended to valuing drinking water provided by surface water supplies, and also to valuing alternative levels of water quality. The theory and case studies discussed in the book suggest that important determinants of the economic value of water quality include: the probability of contamination measured objectively and subjectively, information on actual levels of contamination in household water supplies, socioeconomic characteristics of households, and the extent to which the values of water quality people hold include non-use components. The case study results also suggest that empirical valuation results are sensitive to study design effects such as the particular statistical technique used to estimate mean or median values. These results suggest that estimating water quality values using benefits transfer techniques is problematic, but perhaps feasible with improved data and valuation models. Government agencies, private consulting firms and NGOs involved in water quality policy as well as academic researchers, professors and students will find this volume of theory, application and technique an invaluable reference.

It is widely accepted that natural resource wealth, especially in the form of oil and minerals, can be a key factor in inhibiting economic development. Many of the countries that are richest in natural resources - including oil, metals and diamonds - are amongst the world's poorest. Why? Fiscal Policy and the Natural Resources Curse re-examines this ancient, unsolved puzzle, asking why many governments of natural resource-intensive countries are incapable, in a globalised world, of dealing with the natural-resource curse. This book offers a detailed analysis of the power-relationships which underpin the natural resource curse, using both statistical analysis and country case studies from Africa and Latin America to pinpoint the strategies that have enable developing countries to break out of the poverty trap. The book differs from other works on this subject, as it not only identifies the issues at stake but also offers solutions in the form of a series of suggested policy measures. The work focusses in particular on fiscal escape routes, namely measures to develop and diversify the tax system, and to reallocate and target public expenditure. This volume will be of great interest to scholars of economic development, the economics of natural resources and economic growth as well as all those with an interest in development, global politics and anti-poverty policies.

Accounting literature has viewed sustainability in terms of social, economic and environmental performances. There have been concerns that the relationship between sustainability, accounting and organizational performance cannot be explained unless we can deduce patterns of administrative behaviour that chronicle management practices. Ecology, Sustainable Development and Accounting argues that, despite the broader social and economic development dimensions of sustainability and the limitations of its extension to corporate and organizational behaviour; an ecological framework is capable of providing the overall societal and community chronologies that describe corporate sustainable operations. Drawing examples from international development and federal government organizations, this book documents the link between ecology, corporate sustainable development, and sustainability accounting and reporting. It draws together the literature from several disciplines to elaborate the contribution of the ecological approach to sustainable development in the accounting literature. This book will be of particular interest to students, academics and practitioners in the areas of environmental studies, ecological economics, sustainable development studies, and social and environmental accounting. The sociological and anthropological perspectives make this book the first of its kind to apply the population ecology of sociology to both the sustainability and accounting literature.

A 'green economy' must be built on 'green jobs' - the kind of employment that is low carbon, intended to reduce energy use and expected to restore environmental quality. But attempts to define exactly what a 'green job' is have led to varied and often contradictory answers. There are many unresolved questions including whether we consider jobs in the nuclear fuel industry to be green jobs? Or is a worker at a glass making company which supplies the glass for the solar photovoltaic industry doing a green job given that glass making is a 'dirty' industry? This book deals with the relationship between "green" concepts (green jobs, green economy, green growth) and sustainable development. It examines to which extent creation of green jobs supports overall economic development as opposed to creation of elitist jobs and greenwashing. In order to do so, general conceptual frameworks for green jobs, green economy, green growth and green policy are presented as well as their implementation in ten countries selected among the Group of Twenty. The selection includes advanced (the European Union, the United States of America, Australia, Canada, Republic of Korea, Japan) and developing countries (Mexico, China, Turkey and Brazil). The analysis presented in this book shows that although green concept is well-intentioned, its implementation depends on local circumstances - economic, political and social. Developed countries perceive green growth as a way to create new markets and demand, while developing countries rely more on labor intensive growth and less expensive green jobs. Thus, greening the economy does not diminish differences between rich and poor. This book is suitable for those who study and work in Ecological Economics, Sustainable Development and Labor Economics.

This book studies the limits imposed by the depletion of fossil fuels and the requirements of climate stabilization on economic growth with a focus on China. The book intends to examine the potentials of various energy resources, including oil, natural gas, coal, nuclear, wind, solar, and other renewables, as well as energy efficiency. Unlike many other books on the subject, this book intends to argue that, despite the large potentials of renewable energies and energy efficiency, economic growth eventually will have to be brought to an end as China and the world undertake the transition from fossil fuels to renewable energies. China has overtaken the US to become the world's largest energy consumer and greenhouse gas emitter. Their energy consumption is dominated by coal and China now accounts for one quarter of the world's total carbon dioxide emissions. Moreover, China is set to become the world's largest oil importer in the next decade. This book will consider energy development in the broader context of economic and social changes, especially the historical dynamics of the capitalist world system. Historical lessons of capitalism and socialism will be discussed. The book will evaluate the implications of ecological limits to growth on the economic system and argue that the existing capitalist system is fundamentally incompatible with ecological sustainability.

This title includes a number of Open Access chapters. This valuable compendium provides an overview of the variables and consequences of oceanic carbon cycling in the context of climate change. The chapters highlight the importance of marine plankton in carbon processing as well as the effects of rising CO2 and temperature in their functioning. Marine ecosystems are being increasingly threatened by growing human pressures, including climate change. Understanding the consequences that climate change may have is crucial to predict the future of our oceans. Rising temperatures and ocean acidification may profoundly alter the mode of matter and energy transformation in marine ecosystems, which could have irreversible consequences for our planet on ecological timescales. For that reason, the scientific community has engaged in the grand challenge of studying the variables and consequences of oceanic carbon cycling in the context of climate change, which has emerged as a relevant field of science. The book is broken into four sections: Understanding the Importance of Ocean Biogeochemistry Quantifying Oceanic Carbon Variables Phytoplankton and Oceanic Carbon Cycle Ocean Acidification Edited by a researcher with many years of experience and with contributions from scientists from around the world, this volume explores the most important topics on climate change and oceanic carbon cycling.

International environmental agreements provide a basis for countries to address ecological problems on a global scale. However, countries are heterogeneous with respect to their economic structures and to the problems relating to the environment that they encounter. Therefore, economic externalities and global environmental conflicts are common and can cause problems in implementation and compliance with international agreements. Economics of International Environmental Agreements illuminates those issues and factors that might cause some countries or firms to take different positions on common problems. This book explores why international environmental agreements deal with some problems successfully but fail with others. The chapters address issues that are global in nature, such as: transboundary pollution, provision of global public goods, individual preferences of inequality- aversion, global cooperation, self-enforcing international environmental agreements, emission standards, abatement costs, environmental quota, technology agreement and adoption and international institutions. They examine the necessary conditions for the improved performance of international environmental agreements, how cooperation among countries can be improved and the incentives that can be created for voluntary compliance with international environmental agreements. This text is of great importance to academics, students and policy makers who are interested in environmental economics, policy and politics, as well as environmental law.

The Economics of Green Growth investigates the possibility of creating an integrated indicator covering three pillars of sustainable development: economy, society and the environment. The excessive pursuit of economic efficiency has resulted in severe environmental problems such as climate change and biodiversity loss, and societal human issues such as inequality and disparity. The book aims to change the direction of economic growth towards one which is more sustainable. It explores beyond the conventional indicator, the GDP that measures economic growth and human well-being. It also introduces new indicators relevant to sustainable development and a green economy and discusses the key issues for these indicators.

There has been an explosion in the literature and research on environmental and resource economics in recent years. This major annual publication provides a cutting-edge survey of current research by the leading experts in the field. The latest Yearbook includes contributions on: economics and the land use-environment link issues in the economics of water use the economics of residential solid waste management population and the environment subsidiarity, federalism and the environment transboundary pollution and international cooperation environmental valuation and standard economic theory.