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	Provedor de dados AgEcon (32) Autor Pin, Paolo (4) Kinateder, Markus (3) Golub, Benjamin (2) Jackson, Matthew O. (2) Mengel, Friederike (2) Agbaglah, Messan (1) Boncinelli, Leonardo (1) Buchenrieder, Gertrud (1) Buechel, Berno (1) Buskens, Vincent (1) Chen, Xi (1) Conley, Timothy G. (1) Dall'Asta, Luca (1) Dooan, Gonul (1) Dufhues, Thomas (1) Ehlers, Lars (1) Fischer, Isabel (1) Fosco, Constanza (1) Franz, Silvio (1) Gallo, Edoardo (1) Mais... Palavra-chave D85 (32) C72 (13) Institutional and Behavioral Economics (12) Networks (8) Environmental Economics and Policy (7) C73 (5) Network Formation (5) Social Networks (5) Network (4) Z13 (4) C92 (3) Community/Rural/Urban Development (3) D83 (3) Efficiency (3) Game Theory (3) H41 (3) L14 (3) Nash Equilibrium (3) Research Methods/ Statistical Methods (3) Resource /Energy Economics and Policy (3) Mais... Tipo do documento Working or Discussion Paper (28) Conference Paper or Presentation (3) Working Paper (1) Ano 2011 (5) 2010 (7) 2009 (9) 2008 (6) 2007 (3) 2006 (1) 2004 (1) Mais... País United States (32) Idioma Inglês (32)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 32 Primeira ... 1 2 ... Última Social Networks in Ghana AgEcon Udry, Christopher R.; Conley, Timothy G.. In this chapter we examine social networks among farmers in a developing country. We use detailed data on economic activities and social interactions between people living in four study villages in Ghana. It is clear that economic development in this region is being shaped by the networks of information, capital and influence that permeate these communities. This chapter explores the determinants of these important economic networks. We first describe the patterns of information, capital, labor and land transaction connections that are apparent in these villages. We then discuss the interconnections between the various economic networks. We relate the functional economic networks to more fundamental social relationships between people in a reduced form... Tipo: Working or Discussion Paper Palavras-chave: Endogenous networks; Informal credit; Social learning; Institutional and Behavioral Economics; O12; D85. Ano: 2004 URL: http://purl.umn.edu/28488 Cournot Competition on a Network of Markets and Firms AgEcon Ilkilic, Rahmi. Suppose markets and firms are connected in a bi-partite network, where firms can only supply to the markets they are connected to. Firms compete a la Cournot and decide how much to supply to each market they have a link with. We assume that markets have linear demand functions and firms have convex quadratic cost functions. We show there exists a unique equilibrium in any given network of firms and markets. We provide a formula which expresses the quantities at an equilibrium as a function of a network centrality measure. Tipo: Working or Discussion Paper Palavras-chave: Cournot Markets; Networks; Nash Equilibrium; Centrality Measures; Institutional and Behavioral Economics; C62; C72; D85; L11. Ano: 2009 URL: http://purl.umn.edu/50679 Diffusion of Innovations on Community Based Small Worlds: the Role of Correlation between Social Spheres AgEcon Tanimura, Emily. Which types of networks favor the diffusion of innovations in the sense that an innovation whose intrinsic benefits are greater than those of an established choice will be able to replace the latter when it is initially used only by a small fraction of a large population? For deterministic and regular networks there are characterizations, based on a coordination game model of the diffusion of innovations. Here we study this question for a class of irregular random networks, Small world networks, which are of interest as more realistic models of social networks. We consider a random graph model based on a community structure, in which the choice of a parameter allows us to obtain as special cases several well known models, in particular Watts' Small world.... Tipo: Working or Discussion Paper Palavras-chave: Diffusion of innovations; Small World Networks; Contagion Threshold; Community Structure; Social Networks; Environmental Economics and Policy; D85. Ano: 2010 URL: http://purl.umn.edu/96842 Rural networks in the funding period 2007-2013: A critical review of the EU policy instrument. AgEcon Marquardt, Doris. Rural Networks have been implemented as an instrument to enhance EU rural development policies in the funding period 2007-2013. Gaps in European programme documents concerning the networks’ purpose and their evaluation led to a survey of the National Network Units being conducted in 2010. Besides investigating how these gaps are bridged nationally, the survey aimed to provide an overview of the development of the networks, of the initial experiences and challenges faced in running the networks, and to assess their potential impact. Empirical findings show that the networks probably support rural development (policies) and create added value. However, ways of demonstrating this impact in quantitative terms are lacking. Member states tend to stick closely to... Tipo: Working or Discussion Paper Palavras-chave: National Rural Networks; Policy Instrument; Rural Development; CAP; Agribusiness; Agricultural and Food Policy; Agricultural Finance; Community/Rural/Urban Development; International Development; Land Economics/Use; Resource /Energy Economics and Policy; Q18; D85. Ano: 2011 URL: http://purl.umn.edu/109517 Repeated Games Played in a Network AgEcon Kinateder, Markus. Delayed perfect monitoring in an infinitely repeated discounted game is modelled by allocating the players to a connected and undirected network. Players observe their immediate neighbors’ behavior only, but communicate over time the repeated game’s history truthfully throughout the network. The Folk Theorem extends to this setup, although for a range of discount factors strictly below 1, the set of sequential equilibria and the corresponding payoff set may be reduced. A general class of games is analyzed without imposing restrictions on the dimensionality of the payoff space. Due to this and the bilateral communication structure, truthful communication arises endogenously only under additional conditions. The model also produces a network result; namely,... Tipo: Conference Paper or Presentation Palavras-chave: Repeated Game; Delayed Perfect Monitoring; Network; Communication; Research Methods/ Statistical Methods; C72; C73; D85. Ano: 2008 URL: http://purl.umn.edu/6377 Does Network Matter in International Expansion? Evidence from Italian SMEs AgEcon Petruzzellis, Luca; Gurrieri, Antonia Rosa. In order to face the new competitive scenario, Apulian textile firms are involved in a process of change and are trying to adopt a networking approach in analysing the international propensity of SMEs. The case of the textile network in Apulia has been analysed using a semi-structured questionnaire submitted to a sample of family businesses in order to verify the influence of network on their internationalisation process. The contribution that the network can give to the single firm in its internationalisation process depends also on the level of cooperation in the network. In fact, relationships – at least dual vertical relationships – are the key to overcoming size limit and providing value to all the partners involved. The research attempted to offer a... Tipo: Working or Discussion Paper Palavras-chave: Internationalisation Strategies; Network Approach; L2; D85. Ano: 2008 URL: http://purl.umn.edu/42918 New responsibilities of agriculture: structural differences in stakeholder networks and intentions towards climate change abatement strategies in peatland AgEcon Hübner, Rico; Kantelhardt, Jochen. Agriculture is required to fulfil the needs and wants of society in a variety of fields: food supply, environmental services, landscape preservation and finally: climate mitigation. Using the example of land-use change in peatland in order to create possibilities for greenhouse-gas reduction, a survey about the intentions and future expectations of stakeholders was undertaken. The underlying network structure of these stakeholders in three representative peatland areas of Germany was determined and compared. The results show that considerable differences exist in the degree of knowledge about climate change and in the willingness to cooperate. Depending on the area studied, the most influential political entities are different and thus require different... Tipo: Conference Paper or Presentation Palavras-chave: Land-use in peatland areas; Network analysis; Climate change mitigation.; Land Economics/Use; D83; D85; L31; Q54.. Ano: 2009 URL: http://purl.umn.edu/51059 Power in the Heterogeneous Connections Model: The Emergence of Core-Periphery Networks AgEcon Persitz, Dotan. The heterogeneous connections model is a generalization of the homogeneous connections model of Jackson and Wolinsky (1996) in which the intrinsic value of each connection is set by a discrete, positive and symmetric function that depends solely on the types of the two end agents. Core periphery networks are defined as networks in which the agents' set can be partitioned into two subsets, one in which the members are completely connected among themselves and the other where there are no internal links. A two-type society is defined as "power based" if both types of agents prefer to connect to one of the types over the other, controlling for path length. An exhaustive analysis shows that core periphery networks, in which the "preferred" types are in the... Tipo: Working or Discussion Paper Palavras-chave: Network Formation; Heterogeneity; Pairwise Stability; Institutional and Behavioral Economics; D85; L14. Ano: 2009 URL: http://purl.umn.edu/52338 R&D Collaboration Networks in Mixed Oligopoly AgEcon Zikos, Vasileios. We develop a model of endogenous network formation in order to examine the incentives for R&D collaboration in a mixed oligopoly. Our analysis reveals that the complete network, where each firm collaborates with all others, is uniquely stable, industry-profit maximizing and efficient. This result is in contrast with earlier contributions in private oligopoly where under strong market rivalry a conflict between stable and efficient networks is likely to occur. A key finding of the paper is that state-owned enterprises may be used as policy instruments in tackling the potential conflict between individual and collective incentives for R&D collaboration. Tipo: Working or Discussion Paper Palavras-chave: Networks; R&D Collaboration; Mixed Oligopoly; Research and Development/Tech Change/Emerging Technologies; C70; L13; L20; L31; L32; O31; D85. Ano: 2008 URL: http://purl.umn.edu/6228 SOCIAL CAPITAL AND RURAL DEVELOPMENT: LITERATURE REVIEW AND CURRENT STATE OF THE ART AgEcon Dufhues, Thomas; Buchenrieder, Gertrud; Fischer, Isabel. Social capital has been recently held up as a conceptual framework to build a bridge between the diverse disciplines involved in rural development. However, despite its potential and the impressively rapid take-up of the concept by the community of development professionals, it remains an elusive construct. No definition is yet generally accepted and many definitions are in use. Recently, social capital in the form of social networks has gained much attention in rural development theory and empirical research. But social networks or structural components of social capital are a largely missing dimension in income and poverty analysis. Moreover, most research on social capital assumes that it is a uniform entity. Therefore, the effects of different forms of... Tipo: Working or Discussion Paper Palavras-chave: Sozialkapital; Individuelles Sozialkapital; Sozialkapitalmessung; Ego-zentriertes Netzwerk; Soziale Netzwerke; Social capital; Individual social capital; Measuring social capital; Ego-network; Social networks; Community/Rural/Urban Development; Labor and Human Capital; D85; Z13. Ano: 2006 URL: http://purl.umn.edu/92017 Overlapping Coalitions, Bargaining and Networks AgEcon Agbaglah, Messan; Ehlers, Lars. This paper extends the theory of endogenous coalition formation, with complete information and transferable utility, to the overlapping case. We propose a cover function bargaining game which allows the formation of overlapping coalitions at equilibrium. We show the existence of subgame perfect equilibrium and provide an algorithm to compute this equilibrium in the symmetric case. As an application, we establish an interesting link with the formation of networks. Tipo: Working or Discussion Paper Palavras-chave: Overlapping Coalitions; Cover Function; Bargaining; Symmetric Game; Network; Environmental Economics and Policy; C71; C72; C78; D62; D85. Ano: 2010 URL: http://purl.umn.edu/96628 Opportunity and Choice in Social Networks AgEcon Pin, Paolo; Franz, Silvio; Marsili, Matteo. Our societies are heterogeneous in many dimensions such as census, education, religion, ethnic and cultural composition. The links between individuals - e.g. by friendship, marriage or collaboration - are not evenly distributed, but rather tend to be concentrated within the same group. This phenomenon, called imbreeding homophily, has been related to either (social) preference for links with own--type individuals ( choice-based homophily) or to the prevalence of individuals of her same type in the choice set of an individual ( opportunity-based homophily). We propose an indicator to distinguish between these effects for minority groups. This is based on the observation that, in environments with unbiased opportunities, as the relative size of the minority... Tipo: Working or Discussion Paper Palavras-chave: Social Networks; Choice-Based and Opportunity-Based Homophily; Research Methods/ Statistical Methods; Resource /Energy Economics and Policy; D85; J11; J12. Ano: 2008 URL: http://purl.umn.edu/6232 The Repeated Prisoner’s Dilemma in a Network AgEcon Kinateder, Markus. Imperfect private monitoring in an infinitely repeated discounted Prisoner’s Dilemma played on a communication network is studied. Players observe their direct neighbors’ behavior only, but communicate strategically the repeated game’s history throughout the network. The delay in receiving this information requires the players to be more patient to sustain the same level of cooperation as in a complete network, although a Folk Theorem obtains when the players are patient enough. All equilibria under exogenously imposed truth-telling extend to strategic communication, and additional ones arise due to richer communication. There are equilibria in which a player lies. The flow of information is related with network centrality measures. Tipo: Working or Discussion Paper Palavras-chave: Repeated Game; Prisoner’s Dilemma; Imperfect Private Monitoring; Network; Strategic Communication; Centrality; Environmental Economics and Policy; C72; C73; D85. Ano: 2010 URL: http://purl.umn.edu/96669 Myopic or Farsighted? An Experiment on Network Formation AgEcon Mantovani, Marco; Kirchsteiger, Georg; Mauleon, Ana; Vannetelbosch, Vincent. Pairwise stability (Jackson and Wolinsky, 1996) is the standard stability concept in network formation. It assumes myopic behavior of the agents in the sense that they do not forecast how others might react to their actions. Assuming that agents are farsighted, related stability concepts have been proposed. We design a simple network formation experiment to test these theories. Our results provide support for farsighted stability and strongly reject the idea of myopic behavior. Tipo: Working or Discussion Paper Palavras-chave: Network Formation; Experiment; Myopic and Farsighted Stability; Environmental Economics and Policy; D85; C91; C92. Ano: 2011 URL: http://purl.umn.edu/108256 Network of Commons AgEcon Ylkilic, Rahmi. A tragedy of the commons appears when the users of a common resource have incentives to exploit it more than the socially efficient level. We analyze the situation when the tragedy of the commons is embedded in a network of users and sources. Users play a game of extractions, where they decide how much resource to draw from each source they are connected to. We show that if the value of the resource to the users is linear, then each resource exhibits an isolated problem. There exists a unique equilibrium. But when the users have concave values, the network structure matters. The exploitation at each source depends on the centrality of the links connecting the source to the users. The equilibrium is unique and we provide a formula which expresses the... Tipo: Working or Discussion Paper Palavras-chave: Tragedy of the Commons; Networks; Nash Equilibrium; Efficiency; Centrality Measures; Research Methods/ Statistical Methods; Resource /Energy Economics and Policy; C62; C72; D85; Q20. Ano: 2008 URL: http://purl.umn.edu/6221 Naive Learning in Social Networks: Convergence, Influence and Wisdom of Crowds AgEcon Jackson, Matthew O.; Golub, Benjamin; Jackson, Matthew O.. We study learning and influence in a setting where agents communicate according to an arbitrary social network and naively update their beliefs by repeatedly taking weighted averages of their neighbors' opinions. A focus is on conditions under which beliefs of all agents in large societies converge to the truth, despite their naive updating. We show that this happens if and only if the influence of the most influential agent in the society is vanishing as the society grows. Using simple examples, we identify two main obstructions which can prevent this. By ruling out these obstructions, we provide general structural conditions on the social network that are sufficient for convergence to truth. In addition, we show how social influence changes when some... Tipo: Working or Discussion Paper Palavras-chave: Social Networks; Learning; Diffusion; Bounded Rationality; Institutional and Behavioral Economics; D85; D83; A14; L14; Z13. Ano: 2007 URL: http://purl.umn.edu/9101 How Homophily Affects Learning and Diffusion in Networks AgEcon Golub, Benjamin; Jackson, Matthew O.. We examine how three different communication processes operating through social networks are affected by homophily - the tendency of individuals to associate with others similar to themselves. Homophily has no effect if messages are broadcast or sent via shortest paths; only connection density matters. In contrast, homophily substantially slows learning based on repeated averaging of neighbors' information and Markovian diffusion processes such as the Google random surfer model. Indeed, the latter processes are strongly affected by homophily but completely independent of connection density, provided this density exceeds a low threshold. We obtain these results by establishing new results on the spectra of large random graphs and relating the spectra to... Tipo: Working or Discussion Paper Palavras-chave: Networks; Learning; Diffusion; Homophily; Friendships; Social Networks; Random Graphs; Mixing Time; Convergence; Speed of Learning; Speed of Convergence; Institutional and Behavioral Economics; D83; D85; I21; J15; Z13. Ano: 2009 URL: http://purl.umn.edu/50718 (Anti-) Coordination in Networks AgEcon Kovarik, Jaromir; Mengel, Friederike; Romero, Jose Gabriel. We study (anti-) coordination problems in networks in a laboratory experiment. Partici- pants interact with their neighbours in a fixed network to play a bilateral (anti-) coordination game. Our main treatment variable is the extent to which players are heterogeneous in the number of connections (neighbors) they have. Other network characteristics are held constant across treatments. We find the following results. Heterogeneity in the number of connections dramatically improves the rate of successful coordination. In addition, even though there is a multiplicity of Nash equilibria theoretically, a very sharp selection is observed empirically: the most connected player can impose her preferred Nash equilibrium almost always and observed Nash equilibria are... Tipo: Working or Discussion Paper Palavras-chave: Game Theory; Networks; Coordination Problems; Experiments; Risk and Uncertainty; C72; C90; C91; D85. Ano: 2010 URL: http://purl.umn.edu/61370 Strategic Network Interdiction AgEcon Hong, Sunghoon. We develop a strategic model of network interdiction in a non-cooperative game of flow. An adversary, endowed with a bounded quantity of bads, chooses a flow specifying a plan for carrying bads through a network from a base to a target. Simultaneously, an agency chooses a blockage specifying a plan for blocking the transport of bads through arcs in the network. The bads carried to the target cause a target loss while the blocked arcs cause a network loss. The adversary earns and the agency loses from both target loss and network loss. The adversary incurs the expense of carrying bads. In this model we study Nash equilibria and find a power law relation between the probability and the extent of the target loss. Our model contributes to the literature of... Tipo: Working or Discussion Paper Palavras-chave: Network Interdiction; Noncooperative Game of Flow; Nash Equilibrium; Power Law; Kalai-Zemel Game of Flow; Environmental Economics and Policy; C72; D85; H56. Ano: 2011 URL: http://purl.umn.edu/108252 The Stability of Exchange Networks AgEcon Dooan, Gonul; van Assen, M.A.L.M.; van de Rijt, Arnout; Buskens, Vincent. This paper develops a formal model of exchange network stability that combines expected value theory (Friedkin 1995) with the economic literature on network dynamics. We identify stable networks up to size 8 for varying costs and investigate whether they are Pareto efficient and egalitarian. Only a very small number of networks are stable. Odd cycles and networks consisting of dyads and at most one isolate are the only egalitarian, efficient, and stable networks for a large cost range. We show that some of these results are generalizable to networks of any size and are independent of using expected value theory. Tipo: Working or Discussion Paper Palavras-chave: Exchange Networks; Stability; Efficiency; Equity; Social Dilemma; Institutional and Behavioral Economics; International Development; D85. Ano: 2007 URL: http://purl.umn.edu/9098 Registros recuperados: 32 Primeira ... 1 2 ... Última

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