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	Provedor de dados 5 (1) Autor Boeer, Simone I. (1) Boetius, Antje (1) Gobet, Angelique (1) Huse, Susan M. (1) Quince, Christopher (1) Ramette, Alban (1) Sogin, Mitchell L. (1) Van Beusekom, Justus E. E. (1) Mais... Palavra-chave 454 pyrosequencing (1) Bacterial diversity (1) Coastal seas (1) Multivariate analysis (1) Rare biosphere (1) Tipo do documento Text (1) Ano 2012 (1) País France (1) Idioma Inglês (1)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 91 Primeira ... 1 2 3 4 5 ... Última A Nonlinear Offset Program to Reduce Nitrous Oxide Emissions Induced by Excessive Nitrogen Application 31 Rosas, Francisco; Babcock, Bruce A.; Hayes, Dermot J.. On average, U.S. farmers choose to apply nitrogen fertilizer at a rate that exceeds the ex post agronomically optimal rate. The technology underlying the yield response to nitrogen rewards producers who over apply in years when rainfall is excessive. The overapplication of nutrients has negative environmental consequences because the nitrogen that is not taken up by the plant will typically volatilize causing N2O emissions, or leach causing water pollution. We present a nonlinear offset program that induces farmers to reduce their nitrogen applications to the level that will be consumed by the plant in a typical year and, as a result, reduce N2O emissions from agriculture. The offset program is nonlinear because of the nonlinear relationship between N2O... Tipo: Working or Discussion Paper Palavras-chave: Carbon offsets; Nitrogen fertilizer; Nitrous oxide; Pollution; Uncertainty; Crop Production/Industries; Environmental Economics and Policy; Production Economics; Risk and Uncertainty. Ano: 2011 URL: http://purl.umn.edu/103914 TRADE LIBERALIZATION IN THE INTERNATIONAL PORK SECTOR: ANALYSIS OF ZERO-FOR-ZERO OPTION 31 Meilke, Karl D.; Hayes, Dermot J.; Surry, Yves R.; Fabiosa, Jacinto F.; Fuller, Frank H.. This paper was presented at the INTERNATIONAL TRADE IN LIVESTOCK PRODUCTS SYMPOSIUM in Auckland, New Zealand, January 18-19, 2001. The Symposium was sponsored by: the International Agricultural Trade Research Consortium, the Venture Trust, Massey University, New Zealand, and the Centre for Applied Economics and Policy Studies, Massey University. Dietary changes, especially in developing countries, are driving a massive increase in demand for livestock products. The objective of this symposium was to examine the consequences of this phenomenon, which some have even called a "revolution." How are dietary patterns changing, and can increased demands for livestock products be satisfied from domestic resources? If so, at what cost? What will be the flow-on... Tipo: Conference Paper or Presentation Palavras-chave: International Relations/Trade. Ano: 2001 URL: http://purl.umn.edu/14546 Dynamics of Biofuel Stock Prices: A Bayesian Approach 31 Du, Xiaodong; Hayes, Dermot J.; Yu, Cindy L.. We use Bayesian Markov Chain Monte Carlo methods to investigate the linkage between the volatility of ethanol security prices and the uncertainty surrounding the profitability of ethanol production and the price variations of non-ethanol energy securities. The joint evolution of return and volatility is modeled as a stochastic process that incorporates jumps in both return and volatility. While a strong and significant correlation is found between the volatility of ethanol securities and profit uncertainty from June 2005 to July 2008, the dynamic pattern of ethanol stock volatility is strikingly similar to that of the S&P 500 energy sector index in the more recent period. Our evidence lends support to the findings in the literature on rational learning... Tipo: Working or Discussion Paper Palavras-chave: Jumps; Rational learning; Stochastic volatility; Technological innovation.; Demand and Price Analysis; Financial Economics; Resource /Energy Economics and Policy. Ano: 2009 URL: http://purl.umn.edu/53825 Crop-Based Biofuel Production under Acreage Constraints and Uncertainty 31 Baker, Mindy L.; Hayes, Dermot J.; Babcock, Bruce A.. A myriad of policy issues and questions revolve around understanding the bioeconomy. To gain insight, we develop a stochastic and dynamic general equilibrium model and capture the uncertain nature of key variables such as crude oil prices and commodity yields. We also incorporate acreage limitations on key feedstocks such as corn, soybeans, and switchgrass. We make standard assumptions that investors are rational and engage in biofuel production only if returns exceed what they can expect to earn from alternative investments. The Energy Independence and Security Act of 2007 mandates the use of 36 billion gallons of biofuels by 2022, with significant requirements for cellulosic biofuel and biodiesel production. We calculate the level of tax credits required... Tipo: Conference Paper or Presentation Palavras-chave: Crop Production/Industries; Resource /Energy Economics and Policy. Ano: 2008 URL: http://purl.umn.edu/6352 CROP INSURANCE RATES AND THE LAWS OF PROBABILITY 31 Babcock, Bruce A.; Hart, Chad E.; Hayes, Dermot J.. Increased crop insurance subsidies have increased the demand for insurance at coverage levels higher than the traditional level of 65 percent. Premium rates for higher levels of yield insurance under the Federal Actual Production History (APH) program equal the premium rate at the 65 percent coverage level multiplied by a rate relativity factor that varies by coverage level but not by crop or region. In this paper, we examine the consistency of these constant rate relativity factors with the laws of probability by determining the maximum 65 percent premium rate that is consistent with a well-defined yield distribution. We find that more than 50 percent of U.S. counties have premium rates for corn, soybeans, and wheat that are not consistent with the laws... Tipo: Working or Discussion Paper Palavras-chave: Risk and Uncertainty. Ano: 2002 URL: http://purl.umn.edu/18345 A Welfare Analysis of the U.S. Ethanol Subsidy 31 Du, Xiaodong; Hayes, Dermot J.; Baker, Mindy L.. Based on a transparent analytical model of multiple markets including corn, ethanol, gasoline, and transportation fuel, this study estimates the welfare changes for consumers and producers resulting from ethanol production and related support polices in 2007. The welfare estimation takes into account the second-best gain from eliminating loan deficiency payments. The results suggest the total social cost is about $0.78 billion for given market parameters. We validate the model’s underlying assumption and test for the results’ sensitivity to assumed parameters. Tipo: Working or Discussion Paper Palavras-chave: Consumer surplus; Deadweight loss; Ethanol; Subsidy; Substitution.; Resource /Energy Economics and Policy. Ano: 2008 URL: http://purl.umn.edu/44538 Meat Exports or Soybean Exports? An Iowa Perspective 31 Hayes, Dermot J.. Tipo: Working or Discussion Paper Palavras-chave: International Relations/Trade. Ano: 1995 URL: http://purl.umn.edu/18319 Towards an Integrated Global Agricultural Greenhouse Gas Model: Greenhouse Gases from Agriculture Simulation Model (GreenAgSiM) 31 Dumortier, Jerome; Hayes, Dermot J.. The Greenhouse Gases from Agriculture Simulation Model (GreenAgSiM) presented in this paper aims to quantify emissions from agricultural activity on a global scale. The model takes emissions into account that are directly attributable to agricultural production, such as enteric fermentation (methane), manure management (methane and nitrous oxide), and agricultural soil management (nitrous oxide). Furthermore, carbon stock differences from land-use change (carbon dioxide) induced by agriculture are included in the model. The model will provide policy makers with information about the greenhouse gas implications of policy changes. Tipo: Working or Discussion Paper Palavras-chave: Agriculture; Greenhouse gas emissions; Land-use change; Methane; Nitrous oxide; Soil carbon.; Resource /Energy Economics and Policy. Ano: 2009 URL: http://purl.umn.edu/49760 THE CHINESE MARKET FOR U.S. PORK EXPORTS 31 Hayes, Dermot J.. China feeds twenty-two percent of the world's population on seven percent of its arable land. In contrast, the U.S. and Canada own seventeen percent of the world's arable land, but feed only five percent of its people. As China's income increases, its people will demand more livestock products, including poultry, dairy, beef, and eggs, and more alcohol. Potential Chinese import demand for pork is examined in this paper. The question facing Chinese policymakers is whether to follow their current policy of food self-sufficiency or allow imports of pork muscle and variety meats. Projections of Chinese production and consumption indicate that, by the year 2007, China could import up to 9.1 million metric tons (product weight equivalent) of pork. The current... Tipo: Working or Discussion Paper Palavras-chave: China trade; Livestock; Feedgrains; Meat; International Relations/Trade; F1. Ano: 1997 URL: http://purl.umn.edu/29173 Biofuels: Potential Production Capacity, Effects on Grain and Livestock Sectors, and Implications for Food Prices and Consumers 31 Hayes, Dermot J.; Babcock, Bruce A.; Fabiosa, Jacinto F.; Tokgoz, Simla; Elobeid, Amani E.; Yu, Tun-Hsiang (Edward); Dong, Fengxia; Hart, Chad E.; Chavez, Eddie C.; Pan, Suwen; Carriquiry, Miguel A.; Dumortier, Jerome. We examined four evolution paths of the biofuel sector using a partial equilibrium world agricultural sector model in CARD that includes the new RFS in the 2007 EISA, a two-way relationship between fossil energy and biofuel markets, and a new trend toward corn oil extraction in ethanol plants. At one extreme, one scenario eliminates all support to the biofuel sector when the energy price is low, while the other extreme assumes no distribution bottleneck in ethanol demand growth when the energy price is high. The third scenario considers a pure market force driving ethanol demand growth because of the high energy price, while the last is a policy-induced shock with removal of the biofuel tax credit when the energy price is high. Standard results hold where... Tipo: Journal Article Palavras-chave: Biofuel; EISA; Ethanol; Tax credit; World agricultural sector model; Agribusiness; Consumer/Household Economics; Crop Production/Industries; Demand and Price Analysis; International Relations/Trade; Livestock Production/Industries; Political Economy; Production Economics; Resource /Energy Economics and Policy; Q13; Q18; Q38. Ano: 2009 URL: http://purl.umn.edu/53093 Impact of Ethanol Production on U.S. and Regional Gasoline Prices and On the Profitability of U.S. Oil Refinery Industry 31 Du, Xiaodong; Hayes, Dermot J.. Using pooled regional time-series data and panel data estimation, we quantify the impact of monthly ethanol production on monthly retail regular gasoline prices. This analysis suggests that the growth in ethanol production has caused retail gasoline prices to be $0.29 to $0.40 per gallon lower than would otherwise have been the case. The analysis shows that the negative impact of ethanol on gasoline prices varies considerably across regions. The Midwest region has the biggest impact, at $0.39/gallon, while the Rocky Mountain region had the smallest impact, at $0.17/gallon. The results also indicate that ethanol production has significantly reduced the profit margin of the oil refinery industry. The results are robust with respect to alternative model... Tipo: Conference Paper or Presentation Palavras-chave: Crack spread; Crude oil prices; Ethanol; Gasoline prices; Resource /Energy Economics and Policy. Ano: 2008 URL: http://purl.umn.edu/6353 The Budgetary and Producer Welfare Effects of Revenue Insurance 31 Hennessy, David A.; Babcock, Bruce A.; Hayes, Dermot J.. The efficiency of redistribution of a government provided revenue insurance program is compared with the 1990 farm program. The results indicate the revenue insurance would be more efficient because it would provide subsidies when and only when revenue is low and marginal utility is high, and it works on the component of the objective function (revenue) that is of greatest relevance to producers. Simulation results indicate that a revenue insurance scheme that guarantees 75 percent of expected revenue to risk-averse producers could provide approximately the same level of benefits as the 1990 program, at as little as one-fourth the cost. Tipo: Working or Discussion Paper Palavras-chave: Risk and Uncertainty. Ano: 1997 URL: http://purl.umn.edu/18628 The Feasibility of Broiler Production in Iowa 31 Hayes, Dermot J.. Tipo: Working or Discussion Paper Palavras-chave: Livestock Production/Industries. Ano: 1996 URL: http://purl.umn.edu/18307 Option Pricing on Renewable Commodity Markets 31 Jin, Na; Lence, Sergio H.; Hart, Chad E.; Hayes, Dermot J.. Options markets on agricultural commodities with maturities that exceed 13 months seldom trade. Our hypothesis is that this market failure is due to the absence of an accurate option pricing model for commodities where mean reversion can be expected. Standard option pricing models assume proportionality between price variance and time to maturity. This proportionality is not a valid assumption for commodities where supply response works to bring prices back to production costs. The model suggests that traditional option pricing models will overprice long-term options on these markets. Tipo: Conference Paper or Presentation Palavras-chave: Commodity futures and option; Price mean reverting; Seasonality; Agricultural Finance; Financial Economics. Ano: 2010 URL: http://purl.umn.edu/60955 The Impact of Ethanol Production on U.S. and Regional Gasoline Markets: An Update to 2012 31 Du, Xiaodong; Hayes, Dermot J.. We update the findings of the impact of ethanol production on U.S. and regional gasoline markets as reported previously in Du and Hayes (2009 and 2011), by extending the data to December 2011. The results indicate that over the period of January 2000 to December 2011, the growth in ethanol production reduced wholesale gasoline prices by $0.29 per gallon on average across all regions. The Midwest region experienced the biggest negative impact of $0.45/gallon, while the regions of East Coast, West Coast, and Gulf Coast experienced negative impacts of similar magnitudes around $0.20/gallon. Based on the data of 2011 only, the marginal impacts on gasoline prices are found to be substantially higher given the increasing ethanol production and higher crude oil... Tipo: Working Paper Palavras-chave: Resource /Energy Economics and Policy. Ano: 2012 URL: http://purl.umn.edu/123722 Lessons from the Danish ban on feed-grade antibiotics 31 Hayes, Dermot J.; Jensen, Helen H.. McDonald's Corporation, one of the largest buyers of meat in the U.S. fast-food industry, recently adopted a policy that prohibits its direct suppliers from using medically important antibiotics as growth promotants in food animals after 2004. Although the implications of such a voluntary ban in the United States remain to be seen, recent experiences in Denmark provide some comparable evidence on the effects for hog production. An economic analysis, compiled from information gleaned from interviews with Danish veterinarians, farmers, economists, and industry analysts, estimates the economic costs of an antibiotics ban on pork producers in the United States. Denmark first imposed a ban in pork production at the finishing stage, which was considered a... Tipo: Working or Discussion Paper Palavras-chave: Antibiotics; Economic costs of regulation; Food safety; Pork production; Livestock Production/Industries. Ano: 2003 URL: http://purl.umn.edu/36919 Speculation and Volatility Spillover in the Crude Oil and Agricultural Commodity Markets: A Bayesian Analysis 31 Du, Xiaodong; Yu, Cindy L.; Hayes, Dermot J.. This paper assesses the roles of various factors influencing the volatility of crude oil prices and the possible linkage between this volatility and agricultural commodity markets. Stochastic volatility models are applied to weekly crude oil, corn, and wheat futures prices from November 1998 to January 2009. Model parameters are estimated using Bayesian Markov chain Monte Carlo methods. The main results are as follows. Speculation, scalping, and petroleum inventories are found to be important in explaining oil price variation. Several properties of crude oil price dynamics are established, including mean-reversion, a negative correlation between price and volatility, volatility clustering, and infrequent compound jumps. We find evidence of volatility... Tipo: Working or Discussion Paper Palavras-chave: Gibbs sampling; Merton jump; Leverage effect; Stochastic volatility.; Agricultural and Food Policy; Resource /Energy Economics and Policy. Ano: 2009 URL: http://purl.umn.edu/50073 The Impact of Price-Induced Hedging Behavior on Commodity Market Volatility 31 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 Livestock Revenue Insurance 31 Hart, Chad E.; Babcock, Bruce A.; Hayes, Dermot J.. This study outlines several possible structures for livestock revenue insurance. The policies take the form of an exotic option—an Asian basket option. The actuarially fair premiums for these policies are equal to the prices of the options they represent. Due to the complexity of pricing Asian basket options, we have combined two techniques for pricing options to reach the actuarially fair premiums. Projected premiums, producer welfare, and program efficiency are evaluated for the insurance products and existing market tools. Using efficiency ratios and certainty equivalent returns, we compare the insurance policies to strategies involving existing futures and options. Tipo: Working or Discussion Paper Palavras-chave: Insurance; Livestock; Revenue; Options; Asian basket option; Premiums; Livestock Production/Industries; Risk and Uncertainty. Ano: 2000 URL: http://purl.umn.edu/18356 Creating a Geographically Linked Brand for High-Quality Beef: A Case Study 31 Clemens, Roxanne; Lawrence, John D.; Hayes, Dermot J.; Babcock, Bruce A.. Worldwide, a segment of consumers can afford to pay substantial price premiums for very high quality agricultural products with attributes those consumers value. At the same time, many U.S. farmers are producing these high-quality products but are not using market mechanisms that allow them to take fullest advantage of price premiums. This paper describes a pilot program developed to commercialize an origin-based collective brand for very high quality beef. We hypothesize that, if successful, the program would create potential for cattle producers to take fuller advantage of price premiums often captured elsewhere in the marketing channel. Specifically, the pilot program analyzed two mechanisms for differentiating and marketing very high quality beef: a... Tipo: Working or Discussion Paper Palavras-chave: Certification mark; Collective brands; Consumer assurance; Geographic origin; Process verification; Marketing. Ano: 2007 URL: http://purl.umn.edu/8509 Registros recuperados: 91 Primeira ... 1 2 3 4 5 ... Última

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