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Registros recuperados: 13
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AN EXAMINATION OF THE STABILITY OF COOPERATION IN A VOLUNTARY COLLECTIVE ACTION: THE CASE OF NONPOINT-SOURCE POLLUTION IN AN AGRICULTURAL WATERSHED 31
Algozin, Kenneth A.; Nelson, Carl H..
This paper addresses the collective action problem of nonpoint-source pollution control in a small agricultural watershed. At issue is the stability of cooperative behavior among a group of farmers, who have voluntarily agreed to discontinue their use of the herbicide atrazine due to high concentrations of the herbicide in a local water supply. Continued cooperation among the group is threatened by the unexpected cancellation of cyanazine, an inexpensive and widely used alternative to atrazine. With cyanazine no longer available, the farmers will face a significant increase in weed control costs if they continue to use products that do not contain atrazine. Is cooperation among the farmers still possible despite the increased cost of cooperating?...
Tipo: Conference Paper or Presentation Palavras-chave: Environmental Economics and Policy.
Ano: 2001 URL: http://purl.umn.edu/20478
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DETERMINANTS OF THE VALUE OF SITE-SPECIFIC INFORMATION (SSI) IN AGRICULTURE: A UNIFYING THEORY TO ANALYZE ITS RELATIVE IMPACTS 31
Rejesus, Roderick M.; Nelson, Carl H..
This paper develops a theoretically consistent behavioral model of farmer decision-making that allows for analysis of the relative impacts of the determinants of SSI value. The model departs from previous literature by assuming that SSI reduces uncertainty, but not eliminate it. Results show that increasing the accuracy (or the "level of informativeness") of SSI, increasing initial wealth, improving management ability to reduce uncertainty in the posterior, and increasing the uncertainty in the prior, increases the value of SSI. Furthermore, mean input use is found to decrease, as SSI becomes more "informative." On the other hand, the value of SSI is found to be decreasing as relative risk aversion increases. These results have policy implications for...
Tipo: Conference Paper or Presentation Palavras-chave: Farm Management; Research Methods/ Statistical Methods.
Ano: 2000 URL: http://purl.umn.edu/21779
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ELLIPTICAL SYMMETRY, EXPECTED UTILITY, AND MEAN-VARIANCE ANALYSIS 31
Nelson, Carl H.; Ndjeunga, Jupiter.
Mean-variance analysis in the form of risk programming has a long, productive history in agricultural economics research. And risk programming continues to be used despite well known theoretical results that choices based on mean-variance analysis are not consistent with choices based on expected utility maximization. This paper demonstrates that the multivariate distribution of returns used in risk programming must be elliptically symmetric in order for mean-variance analysis to be consistent with expected utility choices. Then a statistical test for elliptical symmetry is developed and demonstrated. This test enables researchers to determine when data will produce significant differences between risk programming choices and expected utility choices.
Tipo: Working or Discussion Paper Palavras-chave: Risk and Uncertainty.
Ano: 1997 URL: http://purl.umn.edu/14795
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ENGAGING STUDENTS IN RESEARCH: THE USE OF STRUCTURED PROFESSIONAL DIALOGUE 31
Garcia, Philip; Nelson, Carl H..
Graduate students frequently have difficulty defining, developing, and resolving research problems in a manner consistent with the agricultural economics community. Here, we report on a seminar designed to assist graduate students integrate subject matter courses into independent research proposals through participation in professional dialogue. Professional dialogue involves developing arguments to explain and resolve questions where the explanations are supported by warranted evidence and appropriately qualified. The premise of the seminar is that more active problem solvers are developed using professional dialogue to sharpen critical thinking and writing skills.
Tipo: Conference Paper or Presentation Palavras-chave: Teaching/Communication/Extension/Profession.
Ano: 2003 URL: http://purl.umn.edu/21894
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FARM FINANCIAL STRUCTURE DECISIONS UNDER DIFFERENT INTERTEMPORAL RISK BEHAVIORAL CONSTRUCTS 31
Nelson, Carl H.; Escalante, Cesar L..
An alternative unconstrained expected-utility maximization model of farm debt is developed using the location-scale parameter condition that incorporates the empirically validated hypotheses of decreasing absolute and constant relative risk aversion. Simulation-optimization results based on the old and new model versions provide interesting implications for various levels of risk aversion and initial equity investments.
Tipo: Conference Paper or Presentation Palavras-chave: Risk and Uncertainty.
Ano: 2004 URL: http://purl.umn.edu/34756
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Genetically Modified Crops, an Input Distance Function Approach 31
Gardner, Justin G.; Nehring, Richard F.; Nelson, Carl H..
Our initial findings indicate that GM crops do not contribute to the decline of traditional family farms. We make a significant methodological impact by using the within transformation to remove unobserved individual effects and demonstrate that the within transformation results in ML estimates that are identical to OLS estimates.
Tipo: Conference Paper or Presentation Palavras-chave: Production Economics; Genetically Modified Crops; Distance Function; Stochastic Frontier Analysis; Production Economics; Research Methods/ Statistical Methods.
Ano: 2008 URL: http://purl.umn.edu/6800
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Genetically Modified Crops and Labor Savings in US Crop Production 31
Gardner, Justin G.; Nelson, Carl H..
In spite of widespread adoption there is mixed evidence as to whether or not adopting Genetically Modified (GM) crops increase farm welfare. One possible reason for widespread adoption is labor savings. Using a treatment effect model we estimate the labor savings associated with adopting a GM crop.
Tipo: Conference Paper or Presentation Palavras-chave: Genetically modified crops; Agricultural biotechnology; Endogeneity; Treatment effects; Survey weights; Crop Production/Industries.
Ano: 2007 URL: http://purl.umn.edu/34919
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Is Foreign Aid Beneficial for Sub-Saharan Africa? A Panel Data Analysis 31
Armah, Stephen E.; Nelson, Carl H..
Significant ambiguity surrounds the magnitude and sign of the effect of foreign aid on economic growth. Foreign aid can potentially augment scarce domestic capital to spur growth but foreign aid can also remove positive incentive to build wealth, stalling growth. This paper characterizes the effect of foreign aid on the growth of Sub-Saharan African countries after correcting endogeneity problems that plague the estimation. Foreign aid is found to be growth promoting given good governance and using fixed effects in a static panel framework. Data from twenty-one Sub-Saharan African countries spanning 1995-2003 was used in the estimation. The finding of a significant foreign aid-growth relationship is pertinent because it suggests that increased aid to Sub...
Tipo: Conference Paper or Presentation Palavras-chave: Food Security and Poverty.
Ano: 2008 URL: http://purl.umn.edu/6356
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OPTIMAL RISK MANAGEMENT, RISK AVERSION, AND PRODUCTION FUNCTION PROPERTIES 31
Loehman, Edna T.; Nelson, Carl H..
For production risk with identified physical causes, the nature of risk, production characteristics, risk preference, and prices determine optimal input use. Here, a two-way classification for pairs of inputs – each input as being risk increasing or decreasing and pairs as being risk substitutes or complements – provides sufficient conditions to determine how risk aversion should affect input use. Unlike the Sandmo price risk averse firm may produce more expected output and use more inputs than a risk neutral firm. Sufficient conditions to determine types for pairs of inputs are also related to properties of the production function.
Tipo: Journal Article Palavras-chave: Production Economics; Risk and Uncertainty.
Ano: 1992 URL: http://purl.umn.edu/30950
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Relaxing Standard Hedging Assumptions in the Presence of Downside Risk 31
Mattos, Fabio; Garcia, Philip; Nelson, Carl H..
The purpose of this study is to analyze how the introduction of a downside risk measure and less restrictive assumptions can change the optimal hedge ratio in the standard hedging problem. Based on a dataset of futures and cash prices for soybeans in the U.S., the empirical findings indicate that optimal hedge ratios change dramatically when a one-sided risk measure is adopted and standard assumptions are relaxed. Further, the results suggest that in a downside risk framework with realistic hedging assumptions there is little or no incentive for farmers to hedge.
Tipo: Conference Paper or Presentation Palavras-chave: Marketing.
Ano: 2005 URL: http://purl.umn.edu/19040
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STOCHASTIC TECHNOLOGY, RISK PREFERENCES, AND THE USE OF POLLUTING INPUTS 31
Shankar, Bhavani; Nelson, Carl H.; Braden, John B..
We investigate the comparative static effects of environmental and agricultural policies on pesticide and fertilizer use. Since such effects depend on technology and risk preference parameters, we estimate these from a panel data set of Illinois farms. Generalized method of moments is used on a set of nonlinear first order conditions.
Tipo: Conference Paper or Presentation Palavras-chave: Environmental Economics and Policy.
Ano: 1998 URL: http://purl.umn.edu/21011
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The Impact of Measurement Error on Estimates of the Price Reaction to USDA Crop Reports 31
Aulerich, Nicole M.; Irwin, Scott H.; Nelson, Carl H..
This paper investigates the impact of USDA crop production reports in corn and soybean futures markets. The analysis is based on all corn and soybean production reports released over 1970-2006. The empirical analysis compares the typical OLS event study approach to the new Identification by Censoring (ITC) technique. Corn and soybean production reports are analyzed both separately and together for impact in corn and soybean futures prices. ITC proves to be the more useful method because it avoids the pitfalls of errors in variables that cause downward bias in OLS coefficients. Price reaction coefficients estimated via ITC are one to four times larger than OLS estimates for a one price and one event analysis. In the two price, two event case, ITC estimates...
Tipo: Conference Paper or Presentation Palavras-chave: Event study; USDA Crop Production reports; Measurement error; Identification Through Censoring.
Ano: 2007 URL: http://purl.umn.edu/37579
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TOWARD UNDERSTANDING HOUSEHOLD PREFERENCE FOR MILLET VARIETIES IN THE WEST AFRICAN SEMI-ARID TROPICS 31
Ndjeunga, Jupiter; Nelson, Carl H..
In this study, we evaluate the preference of consumers in Niger for different tuwo or couscous characteristics using conjoint analysis. Data were collected through a structured survey administered at 4 sites. Preferences are estimated for three products (couscous, fermented tuwo and nonfermented tuwo) made from 5 pearl millet cutivars. We provide relative valuation for different traits by type of product. Results show that product taste, visual characteristics, and textural attributes are important. The different valuation of characteristics across products and ethnic groups, however, suggests that signals regarding preferences may be very noisy. Consequently, it might be difficult to design pearl millet improvement programs, or food processing...
Tipo: Conference Paper or Presentation Palavras-chave: Pearl millet genetics; Characteristics; Conjoint analysis; Food processing; Food Consumption/Nutrition/Food Safety.
Ano: 2000 URL: http://purl.umn.edu/21883
Registros recuperados: 13
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