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This long-awaited two-volume book examines how the interplay of ideas and actions applied to environmental problems has laid the foundations for global environmental management. It looks at how ideas, interests, and institutions affect management practice; how management capabilities in other areas affect the ability to deal with specific environmental issues; and how learning affects society's approach to the global environment.The book focuses on efforts to deal with climate change, ozone depletion, and acid rain from 1957 (The International Geophysical Year) through 1992 (the UN Conference on Environment and Development). The settings include Canada, Germany, Hungary, Japan, Mexico, the Netherlands, the former Soviet Union, the United Kingdom, the United States, and international environmental organizations. Topics include problem framing, agenda setting, issue attention, risk assessment, monitoring, option assessment, goal and strategy formulation, implementation, and evaluation. Volume 1 provides an overview of the project, of global environmental management in general, and of the three central environmental issues studied; it also contains the individual country studies. Volume 2 contains the management function studies and the book's conclusion.Authors in the set includeJeannine Cavender-Bares, William C. Clark, Ellis Cowling, Nancy M. Dickson, Gerda Dinkelman, Rodney Dobell, Renate Ell, Adam Fenech, Alexander Ginzburg, Elena Goncharova, Peter Haas, Eva Hizsnyik, Michael Huber, Peter Hughes, Jill Jager, Marc Levy, Angela Liberatore, Diana Liverman, Justin Longo, David McCabe, Donald Munton, Elena Nikitina, Karen O'Brien, Edward Parson, Vladimir Pisarev, Ruud Pleune, Miranda Schreurs, Simon Shackley, Peter Simmons, Heather Smith, Vassily Sokolov, Ferenc L. Toth, Jeroen van der Sluijs, Josee van Eijndhoven, Claire Waterton, Cor Worrell, and Brian Wynne.More information is available from the SLG web site.

Ende der 1990er Jahre setzte ein zu diesem Zeitpunkt beispielloser Preisanstieg auf dem US-Eigenheimmarkt ein. Dessen dramatischer Einbruch im Jahre 2006 gilt als einer der Hauptgründe für die noch immer anhaltende Rezession der Weltwirtschaft. Obschon durch niedrige Zinssätze und Kreditvergabekonditionen begünstigt, liefert erst eine Betrachtung der epidemieartigen Ausbreitung von Optimismus über die zukünftige Marktentwicklung eine Erklärung für die Ausmaße dieser "Eigenheim-Blase". Das Verständnis solcher sozialen Herdenphänomene ist daher ökonomisch und sozialpolitisch von großer Bedeutung. Bestehende ökonomische Modelle zum "Sozialen Lernen" nehmen in diesem Bestreben eine zentrale Rolle ein. Diese Modelle zeigen, dass die schnelle Entwicklung von konformem Verhalten oft rational, gleichzeitig jedoch häufig ineffizient oder gar hochgradig schädlich ist. Allerdings sind nicht alle Schlussfolgerungen, welche sich aus den Modellen ergeben, plausibel. Die vorliegende Dissertation stellt daher die Eignung der Modelle zur Erklärung der Phänomene in Frage. Insbesondere werden die lernorientierten Grundlagen des angenommenen strategischen Verhaltens kritisch beleuchtet. Die Ergebnisse münden in der Entwicklung eines Alternativmodells, welches eher in der Lage ist, soziale Herden-phänomene zu erklären. Kapitel 1 ist den bestehenden klassischen Modellen sozialen Lernens gewidmet, welche vollkommene Rationalität und Bayes'sches Verhalten der Entscheider annehmen. Die Schwerpunktsetzung dieser Modelle auf Langfrist-Vorhersagen und den maximalen Informationsgehalt privater Informationen wird hinterfragt. Eine neue Perspektive mit Blick auf mittelfristige Vorhersagen und soziale Wohlfahrt und basierend auf neuen Definitionen u.a. von Konformität wird erarbeitet. Es wird gezeigt, dass höhere Wohlfahrt eng mit der langsameren Entwicklung konformen Verhaltens verknüpft ist. Das zentrale Kapitel 2 untersucht die lerntheoretischen Grundlagen der Modelle. Es steht damit in der ökonomischen Tradition, welche rationales Verhalten als Ergebnis von Anpassungsprozessen versteht. Eine solche dynamische Perspektive ermöglicht daher eine Antwort auf die Frage, ob und warum ein Gleichgewichtsmodell in der Lage ist, tatsächlich beobachtbares Verhalten zu erfassen. Insbesondere kann untersucht werden, welche Kenntnis der Entscheider über die Struktur der Entscheidungssituation vorausgesetzt werden kann. Die Ergebnisse werfen in dieser Hinsicht große Zweifel über die Annahmen bestehender Modelle auf. Genauer gesagt zeigen die Ergebnisse, dass die Vorhersagen der Modelle entscheidend durch eine als zu groß angenommene Kenntnis der Entscheider beeinflusst sind. Dies macht eine Neubewertung sowohl der theoretischen als auch der experimentellen Resultate notwendig. Kapitel 3 schließlich erweitert die bestehenden Modelle um die Präsenz von Individuen, welche Informationen nicht im Sinne von Bayes kombinieren. Es wird gezeigt, dass die Vorhersagen des derart erweiterten Modells besser mit dem in Experimenten beobachtbaren Verhalten übereinstimmen. Insbesondere liefert das erweiterte Modell im Gegensatz zu den bestehenden Modellen eine Erklärung für das wachsende Vertrauen von Individuen in die Richtigkeit des Herdenverhaltens und die daraus resultierende Stabilität desselbigen. ; Home prices in the United States experienced unprecedented growth beginning in the late 1990s, followed by a dramatic downturn in 2006 which caused a global economic recession. Though market fundamentals such as low interest rates and easy mortgage terms boosted housing prices, the full magnitude of the housing bubble can only be reconciled with a social epidemic of optimism for real estate. From a policy perspective, a solid understanding of the idea of social contagion is therefore desirable. Existing economic models of social learning have contributed to this understanding by showing that in many situations the decisions of rational individuals tend to converge quickly and the conformist outcome is often wrong. We argue in this dissertation, however, that some of the conclusions reached by the rational view of social learning are unsound which limits its capacity to explain social epidemics. A thorough investigation of the learning foundations of rational herding enables us to develop an alternative theoretical framework which holds greater promise for explaining social epidemics. Chapter 1 re-examines the classic model of Bayesian rational social learning most commonly investigated in the literature. Previous studies have mainly focused on the long-run properties of the equilibrium outcome in relation with the support of the private belief distribution. From a welfare perspective, this focus on the long-run learning outcome is misplaced. To address this concern, we introduce new measures of uniformity and fragility which enable us to discuss the medium-run properties of the equilibrium outcome. We find that less uniform investment decisions lead to higher welfare levels of the equilibrium outcome but lower fragility of rational herds. Chapter 2, the core of the thesis, investigates the learning foundations of economic models of social learning. We pursue the prevalent idea in economics that rational play is the outcome of a dynamic process of adaptation. Our learning approach offers us the possibility to clarify when and why equilibrium is likely to capture observed regularities in the field. Contrary to the eductive justification for equilibrium, a learning-theoretic model must address the issue of individual and interactive knowledge before the adaptive process starts. We argue that knowledge about the private belief distribution is unlikely to be shared in most social learning contexts. Absent this mutual knowledge, we show that the long-run outcome of the adaptive process favors non-Bayesian rational play. Chapter 3 introduces a simple extension to the rational model of social learning by assuming that players update their beliefs in a non-Bayesian way. We examine the properties of this generalized social learning model and show that it is able to capture the experimental regularities. Unlike standard models of rational social learning, our model predicts that as a herd evolves players tend to quickly become extremely confident about the appropriateness of the chosen action which is why the fragility of the social learning process vanishes over time. Both regularities seem to prevail in social epidemics.

This paper analyzes a model of social learning in a social network. Agents decide whether or not to adopt a new technology with unknown payoffs based on their prior beliefs and the experiences of their neighbors in the network. Using a mean-field approximation, we prove that the diffusion process always has at least one stable equilibrium, and we examine the dependence of the set of equilibria on the model parameters and the structure of the network. In particular, we show how first and second order stochastic dominance shifts in the degree distribution of the network impact diffusion. We find that the relationship between equilibrium diffusion levels and network structure depends on the distribution of payoffs to adoption and the distribution of agents' prior beliefs regarding those payoffs, and we derive the precise conditions characterizing those relationships. For example, in contrast to contagion models of diffusion, we find that a first order stochastic dominance shift in the degree distribution can either increase or decrease equilibrium diffusion levels depending on the relationship between agents' prior beliefs and the payoffs to adoption. Surprisingly, adding more links can decrease diffusion even when payoffs from the new technology exceed those of the status quo in expectation.

Theme [ssh.2013.3.2-1][Social Innovation- Empowering People, changing societies] ; Project Full Title: "Transformative Social Innovation Theory project" ; [Abstract] The object of the present deliverable is the integration of the main outcomes of empirical research and integration activities developed within the TRANSIT project on the cross-cutting theme of "social learning" as well as the distilling of main insights for the development of "practical briefs and tools". Deliverable 2.3 reports on the outcomes of these activities, and consists of the following sections: 1. Working paper: " The role of social learning in transformative social innovations" 2. Synthesis of the third integration workshop: Motivations, relations and transformations. The role of social learning in individual and collective agency for social innovation 3. Social Learning with PEERs: Practitioner Engagement for Empowering Reflections 4. Insights on Social Learning for Transformative Social Innovation Practice (input for practice brief and practice tool. ; This project has received funding from the European Union's Seventh Framework Programme for research, technological development and demonstration under grant agreement no 613169

Governance connotes the way an organization, an economy, or a social system co-ordinates and steers itself. Some insist that governing is strictly a top-down process guided by authority and coercion, while others emphasize that it emerges bottom-up through the workings of the free market. This book rejects these simplistic views in favour of a more distributed view of governance based on a mix of coercion, quid pro quo market exchange and reciprocity, on a division of labour among the private, public, and civic sectors, and on the co-evolution of these different integration mechanisms. This book is for both practitioners confronted with governance issues and for citizens trying to make sense of the world around them.