Home Itens selecionados Provedores de dados OAI Créditos Sobre Ajuda

			Busca avançada
	Provedor de dados ArchiMer (1) Autor Goulletquer, Philippe (1) Palavra-chave Bivalvia (1) Capacité trophique (1) Ecophysiologie (1) Estimation nourriture (1) Estimation production (1) Facteurs environnementaux (1) Mortalité (1) Relation trophique (1) Ruditapes philippinarum (1) Mais... Tipo do documento Text (1) Ano 1989 (1) País France (1) Idioma Francês (1)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 149 Primeira ... 1 2 3 4 5 6 7 8 ... Última A REPRESENTATIVE FARM APPROACH TO OUTREACH WITH BEGINNING FARMERS AND RANCHERS AgEcon Zimmel, Peter; Wilcox, Lori. Tipo: Journal Article Palavras-chave: Beginning Farmers and Ranchers; Representative Farm; Whole Farm Analysis; Risk Management; Online Decision Support; Stochastic; Baseline; Farm Management; Teaching/Communication/Extension/Profession; Q12; Q14; D81. Ano: 2011 URL: http://purl.umn.edu/109477 Do Antibiotics Reduce Production Risk for U.S. Pork Producers? AgEcon Liu, Xuanli; Miller, Gay Y.; McNamara, Paul E.. We combine econometric and financial analyses of the NAHMS 2000 Swine Survey data to examine whether evidence exists for reducing risk by using antibiotics for growth promotion (AGP) in the U.S. swine industry. A stochastic dominance analysis of alternative lengths of time (days) of AGP application reveals that AGP used in the range of 65—75 days is preferred by risk-averse producers. Risk is reduced and profits are increased from use of AGP. The combined impacts of increased average daily gain and decreased variability in pig live weight increase producer profits by $2.99 per pig marketed. Tipo: Journal Article Palavras-chave: Antibiotics; Growth promotion; Pigs; Risk; Stochastic dominance; Variability; D21; D61; D81; Q12; R32. Ano: 2005 URL: http://purl.umn.edu/42785 Land Conversion Pace under Uncertainty and Irreversibility: too fast or too slow? AgEcon Di Corato, Luca; Moretto, Michele; Vergalli, Sergio. In this paper stochastic dynamic programming is used to investigate land conversion decisions taken by a multitude of landholders under uncertainty about the value of environmental services and irreversible development. We study land conversion under competition on the market for agricultural products when voluntary and mandatory measures are combined by the Government to induce adequate participation in a conservation plan. We study the impact of uncertainty on the optimal conversion policy and discuss conversion dynamics under different policy scenarios on the basis of the relative long-run expected rate of deforestation. Interestingly, we show that uncertainty, even if it induces conversion postponement in the short-run, increases the average rate of... Tipo: Working Paper Palavras-chave: Optimal Stopping; Deforestation; Payments for Environmental Services; Natural Resources Management; Risk and Uncertainty; C61; D81; Q24; Q58. Ano: 2011 URL: http://purl.umn.edu/119107 The Impact of Price-Induced Hedging Behavior on Commodity Market Volatility AgEcon Kauffman, Nathan S.; Hayes, Dermot J.. The utility maximization problem of a grain producer is formulated and solved numerically under prospect theory as an alternative to expected utility theory. Conventional theory posits that the optimal hedging position of a producer is not affected solely due to changes in the level of futures prices. However, a strong degree of positive correlation is apparent in the data. Our results show that with prospect theory serving as the underlying behavioral framework, the optimal hedge of a producer is affected by changes in futures price levels. The implications of this price-induced hedging behavior on spot prices and volatility are subsequently considered. Tipo: Conference Paper or Presentation Palavras-chave: Futures markets; Hedging; Prospect theory; Risk preferences; Agribusiness; Institutional and Behavioral Economics; Risk and Uncertainty; D03; D81; G11; Q13. Ano: 2011 URL: http://purl.umn.edu/103242 Regulating Stock Externalities Under Uncertainty AgEcon Newell, Richard G.; Pizer, William A.. Using a simple analytical model incorporating benefits of a stock, costs of adjusting the stock, and uncertainty in costs, we uncover several important principles governing the choice of price-based policies (e.g., taxes) relative to quantity-based policies (e.g., tradable permits) for controlling stock externalities. Applied to the problem of greenhouse gases and climate change, we find that a price-based instrument generates several times the expected net benefits of a quantity instrument. As in Weitzman (1974), the relative slopes of the marginal benefits and costs of controlling the externality continue to be critical determinants of the efficiency of prices relative to quantities, with flatter marginal benefits and steeper marginal costs favoring... Tipo: Working or Discussion Paper Palavras-chave: Stock; Externality; Regulation; Policy; Uncertainty; Price; Quantity; Tax; Tradable permit; Pollution; Climate change; Greenhouse Gas; Instrument choice; Risk and Uncertainty; Q28; D81; C61. Ano: 2000 URL: http://purl.umn.edu/10471 On the (Mis)Use of Wealth as a Proxy for Risk Aversion (PowerPoint) AgEcon Bellemare, Marc F.; Brown, Zachary S.. Tipo: Conference Paper or Presentation Palavras-chave: Risk aversion; Risk; Decision-making; Risk and Uncertainty; D81. Ano: 2009 URL: http://purl.umn.edu/48913 Analyzing Producer Preferences for Counter-Cyclical Government Payments AgEcon Miller, J. Corey; Barnett, Barry J.; Coble, Keith H.. A dynamic-stochastic model is developed to evaluate preferences among alternative countercyclical payment programs for representative farms producing corn or soybeans in Iowa and cotton or soybeans in Mississippi. Countercyclical payment programs are found to not necessarily be preferred to fixed payment programs. Tipo: Journal Article Palavras-chave: Agricultural policy; Bootstrapping; Countercyclical payments; Nonparametric; C15; D81; Q12; Q18. Ano: 2003 URL: http://purl.umn.edu/43203 Eliciting Risk Preferences: A Field Experiment on a Sample of French Farmers AgEcon Bougherara, Douadia; Gassmann, Xavier; Piet, Laurent. We designed a field experiment involving real payments to elicit farmers’ risk preferences. Farmers are a very interesting sample to study since risk has always played an important role in agricultural producers’ decisions. Besides, European farmers may face more risky situations in the future. In this context, it is very important for any economic analysis focusing on agriculture to correctly assess farmers’ behaviour in the face of different sources of risk. We test for two descriptions of farmers’ behaviour: expected utility and cumulative prospect theory. We use two elicitation methods based on the procedures of Holt and Laury (2002) and Tanaka et al. (2010) on a sample of 30 French farmers. The experiment consists in asking subjects to make series of... Tipo: Conference Paper or Presentation Palavras-chave: Risk Attitudes; Field Experiment; Farming; Risk and Uncertainty; C93; D81; Q10. Ano: 2011 URL: http://purl.umn.edu/114266 The Social Discount Rate under Intertemporal Risk Aversion and Ambiguity AgEcon Traeger, Christian P.. The social discount rate crucially determines optimal mitigation policies. This paper examines two shortcomings of the recent debate and the models on climate change assessment. First, removing an implicit assumption of (intertemporal) risk neutrality reduces the growth effect in social discounting and significantly amplifies the importance of risk and correlation. Second, debate and models largely overlook the difference in attitude with respect to risk and with respect to non-risk uncertainty. The paper derives the resulting changes of the risk-free and the stochastic social discount rate and points out the importance of even thin tailed uncertainty for climate change evaluation. Tipo: Working or Discussion Paper Palavras-chave: Ambiguity; Discounting; Expected utility; Intertemporal substitutability; Intertemporal risk aversion; Recursive utility; Risk aversion; Social discount rate; Uncertainty; Political Economy; Risk and Uncertainty; D61; D81; D90; H43; Q00; Q54. Ano: 2009 URL: http://purl.umn.edu/55785 Learning by Doing, Risk Aversion and Use of Risk Management Strategies AgEcon Uematsu, Hiroki; Ashok, Mishra K.. Using a national survey, double hurdle models are estimated to examine the impact of farmers’ risk attitude on use of production and marketing contracts. Risk averse farmers are less likely to use contracts but risk attitude does not have any significant impact on the intensity at which contracts are adopted. Tipo: Conference Paper or Presentation Palavras-chave: Risk attitude; Double hurdle model; Production contracts; Marketing contracts; Agribusiness; Crop Production/Industries; Farm Management; Livestock Production/Industries; Marketing; Risk and Uncertainty; Q10; Q13; D81. Ano: 2011 URL: http://purl.umn.edu/103851 Valuing the Option to Switch to Organic Farming: An Application to U.S. Corn and Soybeans AgEcon Wossink, Ada; Kuminoff, Nicolai V.. Based on option value theory, we develop a theoretical model to assess the dollar compensation required for the conversion to organic farming. Our empirical model is a switching regression model with two regimes and we use county level data on organic and conventional corn and soybean production in the U.S. for the application. Assuming an interest rate of 10 percent, a conventional corn-soybean grower would need to receive a one-time payment of $315 per acre to compensate for the conversion cost and an additional $1,088 per acre to cover the long run higher production and market risks. The sum of these two values equals an annual payment of $228 per acre for a 10 year contact. The results are discussed in the context of the recently introduced... Tipo: Conference Paper or Presentation Palavras-chave: Option theory; Organic farming; Direct payments; Switching regression; Conservation Security Program; Crop Production/Industries; D81; Q18. Ano: 2005 URL: http://purl.umn.edu/24716 Land-use Change and Solar Energy Production: A Real Option Approach AgEcon Ardjan, Gazheli; Di Corato, Luca. In this paper a real option model is developed to examine the critical factors affecting the decision to lease agricultural land to a company installing a PV power plant. The leasing payment is certain while the net revenues from agriculture are uncertain. We identify the profit values at which the farmer decides to lease his plot vs. continue farming it. By applying the model to the province of Bologna (Italy), we illustrate the possible land-use change scenarios in this area. We conclude by discussing the importance of PV energy production as a source of income for farmers and its implications from a social perspective. Tipo: Working Paper Palavras-chave: Land Allocation; Real Options; Renewable Energy; Solar farm; Uncertainty; Resource /Energy Economics and Policy; C61; D81; Q24; Q42. Ano: 2011 URL: http://purl.umn.edu/120041 Hog Producers' Risk Management Attitudes and Desire for Additional Risk Management Education AgEcon Patrick, George F.; Peiter, Amy J.; Knight, Thomas O.; Coble, Keith H.; Baquet, Alan E.. Hog producers in Indiana and Nebraska were surveyed about sources of risk, effectiveness of risk management strategies, and prior participation in and desire for additional risk management education. Ownership of hogs by the producer, size of the operation, and age did have significant effects on ratings of both sources of risk and effectiveness of risk management strategies. Probit analysis found age, prior attendance, knowledge and prior use of the tool, level of integration, and concern about price and performance risk have significant effects on interest in further education about production contracts, futures and options, packer marketing contracts, and financial management. Tipo: Journal Article Palavras-chave: Financial management; Futures and options; Packer marketing contracts; Production contracts; Risk attitudes; Risk management; D81; D83; Q12; Q16. Ano: 2007 URL: http://purl.umn.edu/37110 Subjective Risk, Confidence, and Ambiguity AgEcon Traeger, Christian P.. Tipo: Working or Discussion Paper Palavras-chave: Ambiguity; Subjective beliefs; Expected utility; Intertemporal substitutability; Intertemporal risk aversion; Recursive utility; Uncertainty; Climate change; Risk and Uncertainty; D81; Q54; D90; Q01. Ano: 2010 URL: http://purl.umn.edu/90461 Determinants of the Strength of Strategic Adjustments in Farm Capital Structure AgEcon Escalante, Cesar L.; Barry, Peter J.. This study employs correlation relationships to measure the strength of trade-offs between business and financial risks as a representative of the strategic capital adjustment process. Under different business risk measures based on varying lengths of historical farm income data, results suggest that farmers tend to adopt a myopic perspective when contemplating risk-balancing plans. Cross-sectional regression results for two-time period models covering the decade of the 1980s and 1990s yielded important implications. The liquidity-constrained environment of the 1980s emphasizes the combination of risk-balancing plans, specialization, and market revenue-enhancing strategies. In the 1990s, risk balancing becomes compatible with risk-reducing crop... Tipo: Journal Article Palavras-chave: Business risk; Correlation coefficient measure of risk balancing; Expected utility mean variance model; Financial risk; Risk management strategy; Stochastic interest rates; Strategic capital adjustment; D21; D81; G11; Q12; Q14. Ano: 2003 URL: http://purl.umn.edu/37834 Animal Disease Pre-Event Preparedness versus Post-Event Response: When is it Economic to Protect? AgEcon Elbakidze, Levan; McCarl, Bruce A.. We examine the economic tradeoff between the costs of pre-event preparedness and post-event response to the potential introduction of an infectious animal disease. In a simplified case study setting, we examine the conditions for optimality of an enhanced pre-event detection system considering various characteristics of a potential infectious cattle disease outbreak, costs of postevent response actions. We show that the decision to invest in pre-event preparedness activities depends on such factors as probability of disease introduction, disease spread rate, relative costs, ancillary benefits, and effectiveness of mitigation strategies. Tipo: Journal Article Palavras-chave: Animal disease; Economic balance; Mitigation strategies; Preparedness; Response; Food Consumption/Nutrition/Food Safety; Food Security and Poverty; Livestock Production/Industries; Q1; Q18; D81. Ano: 2006 URL: http://purl.umn.edu/43768 Mixed Tournaments, Common Shocks, and Disincentives: An Experimental Study AgEcon Wu, Steven Y.; Roe, Brian E.; Sporleder, Thomas L.. Two well-known hypotheses from the literature on tournaments are that (1) tournaments can filter out common shocks thereby reducing agents’ risk exposure; and (2) disincentive effects can arise when a tournament scheme is administered on a group of mixed ability agents. While handicapping and/or the creation of homogeneous groups have been suggested as mechanisms for mitigating disincentive effects, it is often impractical to use handicapping schemes and nearly impossible to create a completely homogeneous labor force. Hence, contract administrators who intend to use tournaments to elicit effort must be able to assess the positive effects of tournaments (eliminate common shocks) against the negative effects (disincentive effects). Using economic... Tipo: Conference Paper or Presentation Palavras-chave: Mixed tournaments; Incentives; Relative performance contracts; Experimental economics; Research Methods/ Statistical Methods; C91 D01; D81; D82; D86. Ano: 2007 URL: http://purl.umn.edu/9703 Optimal Conservation Policy Under Imperfect Intergenerational Altruism AgEcon Di Corato, Luca. In this paper we study the optimal forest conservation policy by a hyperbolically discounting society. Society comprises a series of non-overlapping imperfectly altruistic generations each represented by its own government. Under uncertainty about future pay-offs we determine, as solution of an intergenerational dynamic game, the optimal timing of irreversible harvest. Earlier harvest occurs and the option value attached to the forest clearing decision is eroded under both the assumptions of naïve and sophisticated belief about future time-preferences. This results in a bias toward the current generation gratification which affects the intergenerational allocation of benefits and costs from harvesting and conserving a natural forest. Tipo: Working Paper Palavras-chave: Imperfect Altruism; Real Options; Hyperbolic Discounting; Time Inconsistency; Natural Resources Management; Research Methods/ Statistical Methods; D81; C70; Q23; Q58. Ano: 2011 URL: http://purl.umn.edu/120022 A Categorical Data Analysis on Risks in Agriculture AgEcon Uematsu, Hiroki; Mishra, Ashok K.. This study compares farm operators’ risk perceptions and actual realization of risk attitudes revealed through off-farm labor, enterprise diversification, and use of contracts, crop insurance, and other types of insurance, using data from 2001 Agricultural Resource Management Survey (ARMS). Results from ordered logit model and multivariate probit models unexpectedly found that risk loving farmers are more likely to employ risk management strategies. Tipo: Conference Paper or Presentation Palavras-chave: Risk; Agribusiness; Crop Production/Industries; Labor and Human Capital; Marketing; Production Economics; Risk and Uncertainty; D81; Q10; Q12. Ano: 2011 URL: http://purl.umn.edu/98839 AGRICULTURAL PRICE VOLATILITY UNDER CLIMATE CHANGE: The Impact of Multiple Objectives on Commodity Prices AgEcon Fuss, Sabine; Havlik, Petr; Szolgayova, Jana; Obersteiner, Michael; Schmid, Erwin. Agricultural price volatility has moved to the forefront of research efforts and political discussion, where much work is already being undertaken with respect to the impact of fluctuations in input prices (e.g. fertilizer, feed and energy). In this paper we also want to take into account the impact of climate change on prices via increased volatility in crop yields. In addition, we analyze the impact of having multiple objectives competing for the land on which crops are grown. In particular, we want to address the concerns that have been voiced about biofuel targets and calls for prioritization of food security. Tipo: Presentation Palavras-chave: Energy; Food security; Food price volatility; Optimization under uncertainty; Risk and Uncertainty; Q12; Q18; Q28; C61; D81. Ano: 2012 URL: http://purl.umn.edu/122539 Registros recuperados: 149 Primeira ... 1 2 3 4 5 6 7 8 ... Última

Empresa Brasileira de Pesquisa Agropecuária - Embrapa Todos os direitos reservados, conforme Lei n° 9.610 Política de Privacidade Área restrita		Embrapa Parque Estação Biológica - PqEB s/n° Brasília, DF - Brasil - CEP 70770-901 Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco