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Registros recuperados: 37
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A Bayesian Total Factor Productivity Analysis of Tropical Agricultural Systems in Central-Western Africa And South-East Asia AgEcon
Tonini, Axel; Matus, Silvia Saravia; Gomez y Paloma, Sergio.
This paper computes and analyses total factor productivity (TFP) growth rates for tropical agricultural systems in Central-Western Africa and South-East Asia. Two regions that despite sharing common agro-ecological conditions, have pursued different adoption rates of green revolution technology and have reported dissimilar yields per hectare. A panel data set is constructed for the period 1987-2007 from the FAOSTAT database. A Bayesian stochastic frontier model with country specific temporal variation in technical efficiency is estimated. Technical efficiency estimates reveal that there is substantial room for improvement in both continental sub-sets and that TFP estimates show on average larger rates of growth for South-East Asian countries as compared to...
Tipo: Conference Paper or Presentation Palavras-chave: Bayesian Inference; Stochastic Production Frontier; Time Varying Technical Inefficiency; Total Factor Productivity Growth; Tropical Agricultural Systems; Farm Management; Productivity Analysis; C15; D24; O47.
Ano: 2011 URL: http://purl.umn.edu/116088
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A Flexible Parametric Family for the Modeling and Simulation of Yield Distributions AgEcon
Ramirez, Octavio A.; McDonald, Tanya U.; Carpio, Carlos E..
The distributions currently used to model and simulate crop yields are unable to accommodate a substantial subset of the theoretically feasible mean-variance-skewness-kurtosis (MVSK) hyperspace. Because these first four central moments are key determinants of shape, the available distributions might not be capable of adequately modeling all yield distributions that could be encountered in practice. This study introduces a system of distributions that can span the entire MVSK space and assesses its potential to serve as a more comprehensive parametric crop yield model, improving the breadth of distributional choices available to researchers and the likelihood of formulating proper parametric models.
Tipo: Journal Article Palavras-chave: Risk analysis; Parametric methods; Yield distributions; Yield modeling and simulation; Yield nonnormality; Agribusiness; Agricultural Finance; Crop Production/Industries; Land Economics/Use; Production Economics; Productivity Analysis; Research Methods/ Statistical Methods; C15; C16; C46; C63.
Ano: 2010 URL: http://purl.umn.edu/90675
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A NONPARAMETRIC HYPOTHESIS TEST VIA THE BOOTSTRAP RESAMPLING AgEcon
Temel, Tugrul T..
This paper adapts an already existing nonparametric hypothesis test to the bootstrap framework. The test utilizes the nonparametric kernel regression method to estimate a measure of distance between the models stated under the null hypothesis. The bootstraped version of the test allows to approximate errors involved in the asymptotic hypothesis test.
Tipo: Conference Paper or Presentation Palavras-chave: Hypothesis test; The bootstrap; Nonparametric regression; Omitted variables; Research Methods/ Statistical Methods; C12; C14; C15.
Ano: 2001 URL: http://purl.umn.edu/20600
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A Nonparametric Kernel Representation of the Agricultural Production Function: Implications for Economic Measures of Technology AgEcon
Livanis, Grigorios T.; Salois, Matthew J.; Moss, Charles B..
The issue of production function estimation has received recent attention, particularly in agricultural economics with the advent of precision farming. Yet, the evidence to date is far from unanimous on the proper form of the production function. This paper reexamines the use of the primal production function framework using nonparametric regression techniques. Specifically, the paper demonstrates how a nonparametric regression based on a kernel density estimator can be used to estimate a production function using data on corn production from Illinois and Indiana. Nonparametric results are compared to common parametric specifications using the Nadaraya-Watson kernel regression estimator. The parametric and nonparametric forms are also compared in terms of...
Tipo: Conference Paper or Presentation Palavras-chave: Nonparametric regression; Nonparametric derivatives; Gaussian kernel; Optimization techniques; Production function; Production Economics; C14; C15; C16; C61; Q12.
Ano: 2009 URL: http://purl.umn.edu/51063
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A Robust Multivariate Long Run Analysis of European Electricity Prices AgEcon
Bosco, Bruno; Parisio, Lucia; Pelagatti, Matteo; Baldi, Fabio.
This paper analyses the interdependencies existing in wholesale European electricity prices. The results of a multivariate long run dynamic analysis of weekly median prices reveal the presence of a strong although not perfect integration among some neighboring markets considered in the sample and the existence of common long-term dynamics of electricity prices and gas prices but not oil prices. The existence of long-term dynamics among gas prices and electricity prices may prove to be important for long-term hedging operations to be conducted even in markets where there are no electricity derivatives.
Tipo: Working or Discussion Paper Palavras-chave: European Electricity Prices; Cointegration; Interdependencies; Equilibrium Correction Model; Oil Prices; Resource /Energy Economics and Policy; C15; C32; D44; L94; Q40.
Ano: 2007 URL: http://purl.umn.edu/7438
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Agent-Based Modelling and Sensitivity Analysis by Experimental Design and Metamodelling: An Application to Modelling Regional Structural Change AgEcon
Happe, Kathrin.
This paper presents the application of the sensitivity analysis techniques Design of Experiments (DOE) and metamodelling to the agent-based model AgriPoliS, which is a spatial and dynamic simulation model of regional structural change. DOE and metamodelling provide a more systematic analysis of results of complex simulation models. When summarising the results, it becomes clear that interest rates, technical change and managerial ability influence average economic land rent the most.
Tipo: Conference Paper or Presentation Palavras-chave: Simulation; Design of experiments; Metamodelling; Structural change; Research and Development/Tech Change/Emerging Technologies; C9; C15.
Ano: 2005 URL: http://purl.umn.edu/24464
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Agricultural Technology Adoption and Rural Poverty: Application of an Endogenous Switching Regression for Selected East African Countries AgEcon
Asfaw, Solomon; Shiferaw, Bekele A..
Achieving agricultural growth and development and thereby improving rural household welfare will require increased efforts to provide yield enhancing and natural resources conserving technologies. Agricultural research and technological improvements are therefore crucial to increase agricultural productivity and thereby reduce poverty. However evaluation of the impact of these technologies on rural household welfare have been very limited by lack of appropriate methods and most of previous research has therefore failed to move beyond estimating economic surplus and return to research investment. This paper evaluates the potential impact of adoption of modern agricultural technologies on rural household welfare measured by crop income and consumption...
Tipo: Conference Paper or Presentation Palavras-chave: Rural household welfare; Technology adoption; Propensity score matching; Endogenous switching; Ethiopia; Tanzania; Food Security and Poverty; Research and Development/Tech Change/Emerging Technologies; C13; C15; O32; O38.
Ano: 2010 URL: http://purl.umn.edu/97049
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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
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Carbon Mitigation Costs for the Commercial Sector: Discrete-Continuous Choice Analysis of Multifuel Energy Demand AgEcon
Newell, Richard G.; Pizer, William A..
We estimate a carbon mitigation cost curve for the U.S. commercial sector based on econometric estimation of the responsiveness of fuel demand and equipment choices to energy price changes. The model econometrically estimates fuel demand conditional on fuel choice, which is characterized by a multinomial logit model. Separate estimation of end uses (e.g., heating, cooking) using the 1995 Commercial Buildings Energy Consumption Survey allows for exceptionally detailed estimation of price responsiveness disaggregated by end use and fuel type. We then construct aggregate long-run elasticities, by fuel type, through a series of simulations; own-price elasticities range from -0.9 for district heat services to -2.9 for fuel oil. The simulations form the basis of...
Tipo: Working or Discussion Paper Palavras-chave: Commercial energy demand; Carbon policy; Climate change; Discrete choice; Resource /Energy Economics and Policy; Q28; Q48; Q41; C35; C15.
Ano: 2005 URL: http://purl.umn.edu/10625
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Cointegration Analysis of Commodity Prices: Much Ado about the Wrong Thing? AgEcon
Mallory, Mindy L.; Lence, Sergio H..
This study highlights some problems with using the Johansen cointegration statistics on data containing a negative moving average (NMA) in the error term of the data generating process. We use a Monte Carlo experiment to demonstrate that the asymptotic distribution of the Johansen cointegration statistics is sensitive to the NMA parameters and that using the stated 5% critical values results in severe size distortion. In our experiment, using the asymptotic critical values resulted in empirical size of 76% in the worst case. To date a NMA in the error term was known to cause poor small sample performance of the Johansen cointegration statistics; however our study demonstrates that problems associated with a NMA in the error term do not improve as sample...
Tipo: Conference Paper or Presentation Palavras-chave: Cointegration; Johansen cointegration test; Moving average; Agricultural Finance; Financial Economics; C32; C15.
Ano: 2010 URL: http://purl.umn.edu/61721
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Consumer's WTP for Environment-Friendly Production Methods and Collective Reputation for Place of Origin: The Case of Val di Gresta's Carrots AgEcon
Scarpa, Riccardo; Thiene, Mara; Marangon, Francesco.
This paper investigates preferences for various environment-friendly production system for carrots using discretechoice multi-attribute stated-preference data amongst buyers and explore the effect of collective reputations from growers of an Alpine valley known to be completely dedicated to organic production. Results show that buyers distinctly recognize only organic production as a production system different from the conventional one, and there is some evidence of recognition of collective reputation. As well as for marginal utility of income, substantial unobserved heterogeneity is found for many skin imperfections, origin from the organic Alpine valley and the organic production methods. The implied sample distributions of WTP for each of these random...
Tipo: Conference Paper or Presentation Palavras-chave: Choice modelling; Mixed logit; Organic products; Marginal utility of income; Unobserved taste heterogeneity; Status-quo bias; Heteroskedasticity; Crop Production/Industries; Environmental Economics and Policy; C15; C25; Q13; Q18.
Ano: 2006 URL: http://purl.umn.edu/25637
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Economic Comparison of Commodity and Conservation Program Benefits: An Example from the Mississippi Delta AgEcon
Anderson, John D.; Parkhurst, Gregory M..
Changes to commodity programs in the 2002 Farm Bill increased the value of crop base acreages on which decoupled payments are received. The bill also expanded the availability of key conservation programs. This paper compares the value of payments from commodity programs (along with continued crop production) to the easement payment (and recreational lease revenue) available under the Wetland Reserve Program. A net present value model using risk-adjusted returns is employed in the analysis for Mississippi delta cropland containing rice, cotton, and soybean base. Sensitivity analysis is conducted on some of the key variables affecting the decision.
Tipo: Journal Article Palavras-chave: Conservation; Countercyclical payment; Direct payment; Net present value; WRP; Q12; Q15; Q18; C15.
Ano: 2004 URL: http://purl.umn.edu/43390
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El valor de la flexibilidad en la valoracion de inversiones acuícolas AgEcon
Sempere, Loreto Pardo; Alcaide, Jose Javier Rodriguez.
Las fuertes inversiones iniciales que son necesarias para comenzar una actividad acuícola, unidas al período tan dilatado del ciclo de explotación y al riesgo que esta actividad comporta, son situaciones que comprometen el futuro de la actividad cuya continuidad pasa necesariamente por la consecución de la viabilidad económica. Por ello, es importante prestar atención a los estudios que justifiquen esta viabilidad económica considerando aspectos tales como la propia flexibilidad operativa o el valor estratégico que tiene cada proyecto de inversión, a menudo considerados factores críticos para la supervivencia. Desde esta perspectiva, se pone de manifiesto la necesidad y la oportunidad de la investigación, basado en la aplicación del método de Opciones...
Tipo: Journal Article Palavras-chave: Aquaculture; Real Options; Risk; Flexibility in operations; Risk and Uncertainty; B41; C15; D81.
Ano: 2005 URL: http://purl.umn.edu/28786
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Elasticities for U.S. Wheat Food Use by Class AgEcon
Marsh, Thomas L..
We conceptualize wheat for food use as an input into flour production and derive demand functions to quantify price responsiveness and economic substitutability across wheat classes. Cost, price, and substitution elasticities are estimated for hard red winter, hard red spring, soft red wheat, soft white winter, and durum wheat. In general, hard red winter and spring wheat varieties are much more responsive to their own price than are soft wheat varieties and durum wheat. Morishima elasticities indicate that hard red winter and hard red spring wheat are economic substitutes for milling purposes.
Tipo: Conference Paper or Presentation Palavras-chave: Elasticities; Wheat by class; Economic substitution; Monte Carlo; Food Consumption/Nutrition/Food Safety; C15; C30; Q11.
Ano: 2003 URL: http://purl.umn.edu/57920
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Estimating State-Contingent Production Functions AgEcon
Rasmussen, Svend; Karantininis, Kostas.
The paper reviews the empirical problem of estimating state-contingent production functions. The major problem is that states of nature may not be registered and/or that the number of observation per state is low. Monte Carlo simulation is used to generate an artificial, uncertain production environment based on Cobb Douglas production functions with state-contingent parameters. The parameters are subsequently estimated based on different sizes of samples using Generalized Least Squares and Generalized Maximum Entropy and the results are compared. It is concluded that Maximum Entropy may be useful, but that further analysis is needed to evaluate the efficiency of this estimation method compared to traditional methods.
Tipo: Conference Paper or Presentation Palavras-chave: Maximum entropy; State-contingent; Uncertainty; Production; Monte Carlo simulation; Production Economics; C13; C15; D80.
Ano: 2005 URL: http://purl.umn.edu/24529
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Financial and Risk Management Assistance: Decision Support for Agriculture AgEcon
Klose, Steven L.; Outlaw, Joe L..
The Financial and Risk Management (FARM) Assistance program created by Texas Cooperative Extension is a strategic analysis service offered to farmers and ranchers in Texas. The program serves as an example of large-scale, focused programming by extension agencies, as well as the implementation of technical stochastic simulation methods for use on the farm.
Tipo: Journal Article Palavras-chave: Decision information; Decision support system; Extension programming; Farm level analysis; Outreach; Simulation; Q16; Q12; C15; D83.
Ano: 2005 URL: http://purl.umn.edu/43516
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Georeferenced Assessment of Trade Liberalization Effects on Agriculture in Ecuador AgEcon
Ludena, Carlos E.; Schuschny, Andres; de Miguel, Carlos; Duran Lima, Jose E..
As the use of global and national computable general equilibrium (CGE) models has become more widespread, most policies still remain at the regional or sub-national level. This level of disparity requires an approach that bridges the gap between national results and sub-national policies. This study provides a methodology that combines micro-level information and the results of a CGE model with geographical information to spatially map the effects of trade liberalization on the agricultural sector. This methodology enables to distribute changes in value of production for each production unit according to the importance of a specific crop in the political administrative unit. These results show the geographic effects of the FTA on Ecuador's agriculture, and...
Tipo: Conference Paper or Presentation Palavras-chave: Geographic Information Systems (GIS); Computable general equilibrium (CGE); Trade liberalization; Agriculture; Agricultural and Food Policy; International Relations/Trade; C15; R12; Q17.
Ano: 2009 URL: http://purl.umn.edu/50556
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Grain Contracting Strategies to Induce Delivery and Performance in Volatile Markets AgEcon
Wilson, William W..
One of the impacts of higher prices along with greater volatility in futures and basis is that there is pressure for an escalation in cash contracting for grain. This volatility has resulted in an unprecedented level of contracting with growers for specific purchases in recent years. There is a wide array of cash contracts with varying terms. Beyond that array, there is also a growing realization of growers not delivering on contracts, in part due to escalation in post-contract prices. This realization is evolving as a major strategic issue for buyers and the marketing system, particularly as buyers seek to use such contracting strategies as an element of risk mitigation. There are three purposes of this article. First is to provide a broad survey of...
Tipo: Report Palavras-chave: Crop Production/Industries; Farm Management; Financial Economics; C15; D81; Q12.
Ano: 2009 URL: http://purl.umn.edu/55084
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Grain Contracting Strategies to Induce Delivery and Performance in Volatile Markets AgEcon
Wilson, William W.; Dahl, Bruce L..
One of the impacts of higher prices along with greater volatility in futures and basis is that there is pressure for an escalation in cash contracting for grain. This volatility has resulted in an unprecedented level of contracting with growers in recent years. There is a wide array of cash contracts with varying terms. There is also a growing realization of growers not delivering on contracts, in part due to escalation in postcontract prices. These are evolving as major strategic issues for buyers and the marketing system, particularly as buyers seek to use such contracting strategies as an element of risk mitigation. There are three purposes of this article. First is to provide a broad survey of contract terms used in grain contracting with growers....
Tipo: Journal Article Palavras-chave: Grain contracting; Risk; Volatility; Agribusiness; Crop Production/Industries; Farm Management; Production Economics; Risk and Uncertainty; C15; D81; Q12.
Ano: 2009 URL: http://purl.umn.edu/53082
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HEDONIC PRICE FUNCTIONS: GUIDANCE ON EMPIRICAL SPECIFICATION AgEcon
Kuminoff, Nicolai V.; Parmeter, Christopher F.; Pope, Jaren C..
The hedonic pricing model is widely accepted as a method for estimating the marginal willingness to pay for spatially delineated amenities. Empirical applications typically rely on one of three functional forms—linear, semi-log, and double-log—and rarely involve rigorous specification testing. This phenomenon is largely due to an influential simulation study by Cropper, Deck and McConnell (CDM) (1988) that found, among other things, that simpler linear specifications outperformed more flexible functional forms in the face of omitted variables. In the 20 years that have elapsed since their study, there have been major computational advances and significant changes in the way hedonic price functions can be estimated. The purpose of our paper is to update and...
Tipo: Conference Paper or Presentation Palavras-chave: Hedonic; Functional Form; Monte Carlo Simulation; Property Value Model; Demand and Price Analysis; Land Economics/Use; Research Methods/ Statistical Methods; Q15; Q51; Q53; C15; R52.
Ano: 2008 URL: http://purl.umn.edu/6555
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