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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 two-stage productivity analysis using bootstrapped Malmquist index and quantile regression AgEcon
Kaditi, Eleni A.; Nitsi, Elisavet I..
This paper examines the effects of farm characteristics and government policies in enhancing productivity growth for a sample of Greek farms, using a two-stage procedure. In the 1st-stage, non-parametric estimates of Malmquist index and its decompositions are computed, while a bootstrapping procedure is applied to provide their statistical precision. In the 2nd-stage, the productivity growth estimates are regressed on various covariates using a bootstrapped quantile regression approach. The effect that the covariates exert on productivity growth of the average producer is analyzed, as well as the marginal effect of a given covariate for individuals at different points in the conditional productivity distribution. The results indicate that there exists...
Tipo: Conference Paper or Presentation Palavras-chave: Malmquist productivity index; Quantile regression; Bootstrap; Research Methods/ Statistical Methods; C14; C21; D24.
Ano: 2009 URL: http://purl.umn.edu/52845
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Absorption of C14-labeled sucrose by alfalfa nectaries National Institute of Agronomic Research
Pedersen, M.W.; Lefevre, Cecil W..
Tipo: Journal Article-postprint Palavras-chave: ALFALFA; MEDICAGO SATIVA; NECTARY; SUCROSE; ABSORPTION; C14; LUZERNE; MEDICAGO SATIVA; NECTAIRE; SUCROSE; ABSORPTION; C14.
Ano: 1958 URL: http://hdl.handle.net/2174/418
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Adaptive Experimental Design Using the Propensity Score AgEcon
Hahn, Jinyong; Hirano, Keisuke; Karlan, Dean S..
Many social experiments are run in multiple waves, or are replications of earlier social experiments. In principle, the sampling design can be modified in later stages or replications to allow for more efficient estimation of causal effects. We consider the design of a two-stage experiment for estimating an average treatment effect, when covariate information is available for experimental subjects. We use data from the first stage to choose a conditional treatment assignment rule for units in the second stage of the experiment. This amounts to choosing the propensity score, the conditional probability of treatment given covariates. We propose to select the propensity score to minimize the asymptotic variance bound for estimating the average treatment...
Tipo: Working or Discussion Paper Palavras-chave: Experimental design; Propensity score; Efficiency bound; Research Methods/ Statistical Methods; C1; C14; C9; C93; C13.
Ano: 2009 URL: http://purl.umn.edu/47107
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Agricultural Economics Education in Ukrainian Agricultural Universities: An Efficiency Analysis Using Data Envelopment Analysis AgEcon
Lissitsa, Alexej; Coelli, Tim J.; Rao, D.S. Prasada.
Ukraine's transition from a centrally-planned to a market economy has had a profound effect upon its agricultural sector and agricultural universities. A substantial reduction in state financing has forced universities to adopt a range of survival strategies, with varying degrees of success. In this paper we use data envelopment analysis to examine the technical efficiency of 44 agricultural economics programs from 19 Ukrainian universities during the 2002/03 academic year. Our empirical results indicate wide disparities in performance, ranging from 36% to 100% technical efficiency. A second-stage analysis suggests that factors such as student demand, commercial activities and staff quality help explain a portion of this variation.
Tipo: Conference Paper or Presentation Palavras-chave: Higher education; Ukraine; Efficiency; Data envelopment analysis; Teaching/Communication/Extension/Profession; I21; C14; Q16.
Ano: 2005 URL: http://purl.umn.edu/24482
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Agricultural Price Seasonality and Market Failure: Examining the Net Seller Household and the Net Benefit Ratio Definition AgEcon
Vergez, Antonin.
On the basis of a household typology distinguishing between net sellers, net buyers and self sufficient, the Net Benefit Ratio (NBR), defined by Deaton (1989), is used to approximate households' first order welfare variations when price change. In this paper, we discuss both the typology's criteria and the classic formula of NBR, since they are based a) on produced and consumed quantities rather than real marketed volumes and b) on a unique selling and buying price for all surveyed households. We propose another definition of a net seller and a new NBR expression allowing the analyst to take into account market failures (MF) and price seasonality (PS), which are two constancies in developing countries. We use two sets of data (from Mexico and Mali), to...
Tipo: Conference Paper or Presentation Palavras-chave: Household welfare; Food crop; Net buyer; Net seller; Net benefit ratio; Price seasonality; Survey; Consumer/Household Economics; Marketing; D12; C14; Q12; D31; Q17; Q18.
Ano: 2007 URL: http://purl.umn.edu/7911
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An Information-Theoretic Approach to Modeling Binary Choices: Estimating Willingness to Pay for Recreation Site Attributes AgEcon
Henry-Osorio, Miguel; Mittelhammer, Ronald C..
Information-Theoretic Econometrics
Tipo: Presentation Palavras-chave: Minimum power divergence; Cressie-Read statistics; Contingent valuation; Empirical likelihood; Discrete choice; Binary response models; Environmental Economics and Policy; Research Methods/ Statistical Methods; C13; C14; C25; Q51.
Ano: 2012 URL: http://purl.umn.edu/123432
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Analysing Wine Demand With Artificial Neural Networks AgEcon
Gerolimetto, M.; Mauracher, Christine; Procidano, I..
In this paper we analyse wine demand in Italy using microdata. Instead of estimating a traditional parametric model (like AIDS) we employed artificial neural networks (ANN) and evaluate the elasticities using two different methods, specific for the non parametric framework. We compared the performances of the two methods to estimate elasticities and put in evidence the relevance of some demographic variables together with the usual economic ones, explaining the consumer's behaviour.
Tipo: Conference Paper or Presentation Palavras-chave: Artificial neural networks; Demand analysis; Wine; Elasticity; Demand and Price Analysis; C14; C21; Q11; Q13.
Ano: 2005 URL: http://purl.umn.edu/24753
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Applying regression quantiles to farm efficiency estimation AgEcon
Kaditi, Eleni A.; Nitsi, Elisavet I..
This article is concerned with the methodological question of frontier production functions estimation for agriculture, and the appropriateness of regression quantiles, as a useful semi-parametric approach. Better insights are reached using the proposed methodology that provides robust farm efficiency scores estimates. Using the 2007 Farm Accountancy Data Network (FADN) data for Greece, analysis shows that the distribution of efficiency scores is closer to normality when employing regression quantiles, while underestimation of efficiency obtained by other parametric or deterministic methods based on the conditional mean can be avoided. The results further suggest that government support aimed at enhancing farms viability should be directed towards payments...
Tipo: Conference Paper or Presentation Palavras-chave: Efficiency; Quantile Regression; Agriculture; Agricultural and Food Policy; Productivity Analysis; Research Methods/ Statistical Methods; C14; D24; Q18.
Ano: 2010 URL: http://purl.umn.edu/61081
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Are Food Price Differences in EU Member States a Result of the Penn Effect? AgEcon
Fousekis, Panos.
Panel data from 14 EU member states and non parametric techniques are used in this paper to investigate the relationship between food prices and real per capita incomes. The empirical results suggest that the Penn Effect largely holds for Total Food prices but not for the prices of certain among the seven disaggregate food commodities considered. In particular, for Cereals, for Fats and Oils, and for Other food products poorer countries are likely to face prices no lower than those prevailing in richer ones
Tipo: Journal Article Palavras-chave: Food Prices; Living Standards; EU; Agricultural and Food Policy; Q11; C14.
Ano: 2009 URL: http://purl.umn.edu/58057
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Arroz Transgénico en Uruguay: un modelo de simulación para estimar los beneficios económicos potenciales. AgEcon
Hareau, Guy Gaston; Mills, Bradford F.; Norton, George W..
economic surplus, imperfect markets, adoption rate, GMO, monopoly power.
Tipo: Book Palavras-chave: En pequeños países en desarrollo como Uruguay; Los beneficios económicos potenciales que se obtendrían por la adopción de nuevas tecnologías agrícolas basadas en biotecnología están limitados por una base productiva reducida. En este trabajo se evalúa ex - ante el impacto económico de una variedad de arroz transgénico resistente a herbicidas donde el poder de mercado de la multinacional propietaria de la variedad afecta las tasas de adopción a través del margen monopólico en el precio de la semilla. Se emplean métodos de simulación estocástica para estudiar la variación de los resultados a cambios en los parámetros tecnológicos y en las tasas de adopción. La media del excedente económico de los productores es de US$1; 82 millones; Mientras que la ganancia monopólica es de US$0; 55 millones. Estos beneficios económicos relativamente escasos sugieren que; Sin estrategias de política pública que incrementen los beneficios potenciales y reduzcan los costos de investigación; Las multinacionales no invertirían recursos significativos en el desarrollo de una variedad transgénica adaptada a las condiciones locales. Las alianzas con instituciones nacionales y el acceso a mercados regionales ampliados también contribuyen a incrementar los incentivos privados en I&D.; Agricultural and Food Policy; Research and Development/Tech Change/Emerging Technologies; C14; E17; Q16; Q18; Q55.
Ano: 2005 URL: http://purl.umn.edu/121683
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Bounds on Quantile Treatment Effects of Job Corps on Participants' Wages AgEcon
Blanco, German; Flores, Carlos A.; Flores-Lagunes, Alfonso.
This paper assesses the effect of the U.S. Job Corps (JC), the nation's largest and most comprehensive job training program targeting disadvantaged youths, on wages. We employ partial identification techniques and construct informative nonparametric bounds for the causal effect of interest under weaker assumptions than those conventionally used for point identification of treatment effects in the presence of sample selection. In addition, we propose and estimate bounds on quantile treatment effects of the program on participants' wages. In general, we find convincing evidence of positive impacts of JC on participants' wages. Importantly, we find that estimated impacts on lower quantiles of the distribution are higher, with the highest impact being in the...
Tipo: Working or Discussion Paper Palavras-chave: Job Corps; Nonparametric Bounds; Principal Stratification; Active Labor Market Programs.; Labor and Human Capital; Public Economics; Research Methods/ Statistical Methods; J24; J68; C14; C21.
Ano: 2011 URL: http://purl.umn.edu/103761
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COST EFFICIENCY OF CATFISH FARMS IN CHICOT COUNTY, ARKANSAS: THE IMPACT OF EXTENSION SERVICES AgEcon
Engle, Carole R.; Kaliba, Aloyce R..
Cost efficiency measures of a sample of catfish farms in Chicot County, Arkansas are estimated using a data envelopment analysis technique. A measure of overall efficiency is used to determine operator's characteristics, farm practices, and institutional support services that are likely to lead to higher farm level cost efficiency. Results indicate that live catfish production could increase by 55% using the same level of inputs if all farms were operating at the minimum average cost curve. Higher feeding rate and availability of extension services were associated with increased cost efficiency. Higher stocking density affected overall efficiency negatively. The marginal value of extension contacts in Chicot County was estimated to be $2988. This study...
Tipo: Conference Paper or Presentation Palavras-chave: Catfish; Cost efficiency; Data envelopment analysis; And extension services; Resource /Energy Economics and Policy; C14; C24; D61.
Ano: 2004 URL: http://purl.umn.edu/34740
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Does Gibrat's Law Hold Amongst Dairy Farmers in Northern Ireland? AgEcon
Kostov, Philip; Patton, Myles; Moss, Joan E.; McErlean, Seamus.
This paper tests whether the Law of Proportionate Effects (Gibrat, 1931), which states that farms grow at a rate that is independent of their size, holds for the dairy farms in Northern Ireland. Previous studies have tended to concentrate on testing whether the law holds for all farms. The methodology used in this study permits investigation of whether the law holds for some farms or all farms according to their size. The approach used avoids the subjective splitting of samples, which tends to bias results. The finding shows that the Gibrat law does hold except in the case of small farms. This is in accordance with previous findings that Gibrat's law tends to hold when only larger farms are considered, but tends to fail when smaller farms are included in...
Tipo: Conference Paper or Presentation Palavras-chave: Gibrat's law; Quantile regression; Sample selection bias; Integrated Conditional Moments test; Agricultural and Food Policy; C12; C14; O49; Q19.
Ano: 2005 URL: http://purl.umn.edu/24775
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Economic Efficiency Adjusted for Risk Preferences AgEcon
Yeager, Elizabeth A.; Langemeier, Michael R..
This study investigates the impact of risk preferences on economic efficiency scores. Risk averse individuals may be less likely to adopt new technologies and have lower production levels than individuals with other risk preferences. Nonparametric techniques are used to estimate cost and revenue efficiency for a sample of Kansas farms. Each farm had a risk preference score and the scores in the sample ranged from 5 to 86 where a smaller value represents greater risk aversion. Efficiency estimates were first calculated using traditional input and output measures. Efficiency was re-estimated including the inverse risk preference score as a non-discretionary input. Comparisons were made between the characteristics of the farms with an observed...
Tipo: Presentation Palavras-chave: Cost Efficiency; Revenue Efficiency; Risk Preference; Agribusiness; Farm Management; Production Economics; Risk and Uncertainty; C14; D22; D81.
Ano: 2012 URL: http://purl.umn.edu/124012
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Effects on School Enrollment and Performance of a Conditional Transfers Program in Mexico AgEcon
Dubois, Pierre; de Janvry, Alain; Sadoulet, Elisabeth.
We study the effects of a conditional transfers program on school enrollment and performance in Mexico. We provide a theoretical framework for analyzing the dynamic educational decision and process including the endogeneity and uncertainty of performance (passing grades) and the effect of a conditional cash transfer program for children enrolled at school. Careful identification of the program impact on this model is studied. This framework is used to study the Mexican social program Progresa in which a randomized experiment has been implemented and allows us to identify the effect of the conditional cash transfer program on enrollment and performance at school. Using the rules of the conditional program, we can explain the different incentive effects...
Tipo: Working or Discussion Paper Palavras-chave: Education demand; Schooling decisions; School performance; Dynamic decisions; Treatment effects; Transfer program; Randomized experiment; Mexico.; Labor and Human Capital; C14; C25; D91; H52; H53; I21; I28; J24.
Ano: 2003 URL: http://purl.umn.edu/25064
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Efficiency analysis of producers’ organizations (Case of South Eastern and Central planning regions of Bulgaria) AgEcon
Zaimova, Darina.
The main aim of this paper is to compare two alternative methods for estimating frontier functions and measuring efficiency in production. The application of Data Envelopment Analysis (DEA) and Stochastic Frontier Analysis (SFA) to the same data panel provides insights in estimating technical efficiency of producers’ organizations in selected regions in Bulgaria.
Tipo: Journal Article Palavras-chave: DEA; SFA; Technical efficiency; Frontier production; Farm efficiency; Community/Rural/Urban Development; International Development; C14; C23; C51; C61; C67; D24.
Ano: 2010 URL: http://purl.umn.edu/94636
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Efficiency Estimates for the Agricultural Production in Vietnam: A Comparison of Parametric and Non-parametric Approaches AgEcon
Nguyen, Khac Minh; Giang, Thanh Long.
This paper uses both parametric and non-parametric approaches to estimate technical, allocative, and economic efficiencies for the agriculture production in sixty provinces of Vietnam in the period 1990-2005. Under different technology specifications, both approaches show that the average technical, allocative, and economic efficiency estimates were not high, and there would be a large room for the studied provinces to improve their agricultural production efficiency. To examine consistency of the estimates from two approaches under different specifications of returns to scale, we use Spearman rank test, and the results indicate that parametric and non-parametric approaches provide different estimates.
Tipo: Journal Article Palavras-chave: Data envelopment analysis (DEA); Stochastic frontier production function (SFPF); Spearman rank; Production Economics; C14; N5.
Ano: 2009 URL: http://purl.umn.edu/58060
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Explaining Production Inefficiency in China’s Agriculture using Data Envelope Analysis and Semi-Parametric Bootstrapping AgEcon
Monchuk, Daniel C.; Zhuo, Chen.
In this paper we examine more closely the factors associated with production inefficiency in China’s agriculture. The approach we take involves a two-stage process where output efficiency scores are first estimated using data envelope analysis (DEA), and then in the second stage, variation in the resulting efficiency scores are explained using a truncated regression model with inference based on a semi-parametric bootstrap routine. Among the results we find a heavy industrial presence is associated with reduced agricultural production efficiency and may be an indication that externalities from the industrial process, like air and ground water pollution, affect agricultural production. We also find evidence that counties with a large percentage of the rural...
Tipo: Conference Paper or Presentation Palavras-chave: China's agriculture; DEA; Bootstrapping; Technical efficiency; Production Economics; C14; Q1; R5.
Ano: 2008 URL: http://purl.umn.edu/6456
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