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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 strong test of the von Liebig hypothesis AgEcon
Berck, Peter; Geoghegan, Jacqueline; Stohs, Stephen M..
Tipo: Working or Discussion Paper Palavras-chave: Corn; Production function; Von liebig; Wheat; Production Economics.
Ano: 1998 URL: http://purl.umn.edu/43911
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Allocative and Technical Efficiency of Corporate Farms in Russia AgEcon
Grazhdaninova, Margarita; Lerman, Zvi.
This study is aimed to analyze Russian corporate farms technical efficiency using DEA and allocative efficiency basing upon VMP calculations. The estimations are carried out on three aggregation levels: total farm, sectors (livestock and crops production) and selected commodities (grain, sunflower, beef, milk and pork), using survey data. The results of analyses suggest that there is no substantial misallocation of resources given current input and output prices. High technical efficiency scores speak for production technologies being homogeneous and mean that simple extension of "best practice" production will not eliminate the large productivity gap between Russia and the developed market economies.
Tipo: Conference Paper or Presentation Palavras-chave: Transition economies; Productivity; Efficiency; Production function; Data Envelopment Analysis; Agribusiness; D610; P230; Q180.
Ano: 2005 URL: http://purl.umn.edu/24756
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Analysis of Technical Efficiency and Varietal Differences in Pistachio Production in Iran Using a Meta-Frontier Analysis AgEcon
Boshrabadi, Hossain Mehrabi; Villano, Renato A.; Fleming, Euan M..
This paper reports on an analysis of technical efficiency and varietal differences in pistachio production in Iran. A random sample of 475 farmers was selected from the province of Kerman in 2003 and 2004. In this study, farmers are classified into three groups according to the variety of tree they planted. The three main varieties of pistachio trees planted are Kalleh- Ghuchi, Fandoghi and Akbari. The technical efficiency indices are computed using three approaches. First, a standard stochastic production frontier was employed using pooled data. Secondly, stochastic frontier production functions were estimated for each variety (separately). Lastly, the meta-frontier approach was used because production varieties and technologies are expected to differ...
Tipo: Conference Paper or Presentation Palavras-chave: Pistachio; Stochastic meta-frontier; Production function; Technical efficiency; Iranian agriculture; Productivity Analysis; C21; Q12; Q16; Q55; R58.
Ano: 2007 URL: http://purl.umn.edu/10425
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Determinación del óptimo económico en la producción de "setas" (Pleurotus ostreatus) Colegio de Postgraduados
Alemán Morales, Mireya.
La producción de “setas” (Pleurotus ostreatus), es una alternativa para producir y diversificar los alimentos que requiere la población en México. En el país es escasa la información acerca de la rentabilidad de éste cultivo. Por ello, el objetivo de este trabajo fue estimar una función de producción que muestre matemáticamente la relación funcional entre los insumos productivos utilizados y la producción “setas”. La variable dependiente la constituyó la producción de “setas” producidas y la variable independiente fueron las bolsas en producción. Los resultados económicos mostraron que la etapa de producción II, la que es económicamente relevante, se inicia en el punto donde se encuentran en el área de producción 2449 bolsas y termina donde el producto...
Tipo: Tesis Palavras-chave: Función de producción; Pleurotus ostreatus; Optimización; Rentabilidad; “setas”; Production function; Pleurotus ostreatus; Optimisation; Viability; “mushrooms”.
Ano: 2008 URL: http://hdl.handle.net/10521/1417
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Discussão dos retornos à escala nos contextos das funções de produção e de custo AgEcon
Alves, Eliseu Roberto de Andrade.
The article deals with the cost function at a mathematical level that only requires knowledge of differentials, but except for that, it keeps rigor at a high level. It only states theorems that require long proofs. The article justifies the existence of the cost function, points out its properties, and shows how it relates with the production function in the sense that one is the dual to the other. The article discusses partial and scale elasticities, both in the context of production and cost functions. Whenever profit is maximized, one is the reciprocal of the other. The cost function has not a defined form in the sense that it can be deduced from the axioms of production theory. But the articles points out the plausibility of the form that resembles an...
Tipo: Journal Article Palavras-chave: Cost function; Production function; Return to scale; Average cost; Profit; Production Economics.
Ano: 2007 URL: http://purl.umn.edu/54595
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Economic viability of retrofiting emitters in center pivot irrigation systems REA
Zolin,Cornélio A.; Coelho,Rubens D.; Paulino,Janaina; Folegatti,Marcos V..
Although several studies have been conducted to evaluate the uniformity of water application under center pivot irrigation systems, there are few studies concerning the economic perspective of such coefficient. The aim of this study is to present a methodology to accomplish an economic analysis as support for the decision-making to retrofit emitters in center pivot irrigation systems, and to attribute an economic meaning to the uniformity coefficient of water application taking into account the response function productivity to the amount of water applied and the sale price of the crops. In the hypothetic calculation example considering the variation of revenue of potato crop under center pivot irrigation system, it was verified that the area with...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Heermann's uniformity coefficient; Production function; Sale price of crops.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-69162012000300019
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Estimating complex production functions: the importance of starting values AgEcon
Neal, Mark.
Production functions that take into account uncertainty can be empirically estimated by taking a state contingent view of the world. Where there is no a priori information to allocate data amongst a small number of states, the estimation may be carried out with finite mixtures model. The complexity of the estimation almost guarantees a large number of local maxima for the likelihood function. However, it is shown, with examples, that a variation on the traditional method of finding starting values substantially improves the estimation results. One of the major benefits of the proposed method is the reliable estimation of a decision maker’'s ability to substitute output between states, justifying a preference for the state contingent approach over the use...
Tipo: Conference Paper or Presentation Palavras-chave: Production function; Econometrics starting values state contingent production Production Economics.
Ano: 2007 URL: http://purl.umn.edu/10435
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Estrutura da tecnologia de produção agrícola regional: uma abordagem da programação de metas AgEcon
Baptista, Antonio Jose Medina dos Santos; Avila, William Romell Benevides de; Lima, Joao Eustaquio de; Gomes, Adriano Provezano.
The objective of this study was to analyze the average production functions and the frontiers production function to characterize the structure of the agricultural production technology. Using data of the agricultural census of 1995/96 regarding the mesorregião of the Triangulo Mineiro and Alto Paranaíba of the State of Minas Gerais the goal programming was used to calculate the parameters of the Cobb Douglas production functions. One of the main conclusions is the existence of significant differences in the level of productive efficiency and in the structure of the production technologies in this Mesorrregião, indicating the bias that is incurred when making decisions only based on the parameters of the average production function. Another important...
Tipo: Journal Article Palavras-chave: Production function; Goal Programming; Efficiency; Agriculture; Production Economics.
Ano: 2006 URL: http://purl.umn.edu/55306
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EXAMINATION OF ALTERNATIVE HETEROSCEDASTIC ERROR STRUCTURES USING EXPERIMENTAL DATA AgEcon
Mjelde, James W.; Capps, Oral, Jr.; Griffin, Ronald C..
Impacts of alternative specifications for heteroscedastic error structures are examined by estimating various production functions for corn in Central Texas. Production- and profit- maximizing levels of input and the shape of the profit equation obtained from models not corrected for heteroscedasticity differed from those obtained from models corroded for heteroscedasticaity. Using the profit-maximizing input levels for each production function gave essentially the same estimated yield and profit, regardless of the specification for heteroscedasticity employed. Differences of up to one-quarter to one-third are noted, however, in the amount of profit-maximizing levels of input used, depending on the heteroscedasticity correction.
Tipo: Journal Article Palavras-chave: Corn; Heteroscedasticity; Production function; Research Methods/ Statistical Methods.
Ano: 1995 URL: http://purl.umn.edu/15329
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FEEDFORWARD NEURAL NETWORK ESTIMATION OF A CROP YIELD RESPONSE FUNCTION AgEcon
Joerding, Wayne H.; Li, Ying; Young, Douglas L..
Feedforward networks have powerful approximation capabilities without the "explosion of parameters" problem faced by Fourier and polynomial expansions. This paper first introduces feedforward networks and describes their approximation capabilities, then we address several practical issues faced by applications of feedforward networks. First, we demonstrate networks can provide a reasonable estimate of a Bermudagrass hay fertilizer response function with the relatively sparse data often available from experiments. Second, we demonstrate that the estimated network with a practical number of hidden units provides reasonable flexibility. Third, we show how one can constrain feedforward networks to satisfy a priori information without losing their flexible...
Tipo: Journal Article Palavras-chave: Biological process models; Feedforward networks; Production function; Neural networks; Research Methods/ Statistical Methods.
Ano: 1994 URL: http://purl.umn.edu/15430
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Impact of global warming on Chinese wheat productivity AgEcon
You, Liangzhi; Rosegrant, Mark W.; Fang, Cheng; Wood, Stanley.
Climate change continues to have major impact on crop productivity all over the world. While many researchers have evaluated the possible impact of global warming on crop yields using mainly indirect crop simulation models, there are relatively few direct assessments on the impact of observed climate change on past crop yield and growth. We use a 1979-2000 Chinese crop-specific panel dataset to investigate the climate impact on Chinese wheat yield growth. We find that a 1 percent increase in wheat growing season temperature reduces wheat yields by about 0.3 percent. This negative impact is less severe than those reported in other regions. Rising temperature over the past two decades accounts for a 2.4 percent decline in wheat yields in China while the...
Tipo: Working or Discussion Paper Palavras-chave: Global warming; Wheat yield; Production function; Marginal impact; Panel data; Climate; Wheat production; Crop Production/Industries; Environmental Economics and Policy.
Ano: 2005 URL: http://purl.umn.edu/58588
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Increasing Canada's International Competitiveness: Is There a Link between Skilled Immigrants and Innovation? AgEcon
Partridge, Jamie; Furtan, William Hartley.
We use an augmented national ideas production function to examine skilled immigrants' impact on Canadian innovation at the provincial level. Empirically, this model was tested using Canadian data by province on innovation flow over an 11 year time period, where innovation flow is defined in terms of international (U.S.) patents. It was found that skilled immigrants, who are proficient in either English or French, have a significant and positive impact on innovation flow in their home province. Further, in examining skilled immigrants by source region, it was found that skilled immigrants from developed countries have the greatest impact on their home province's innovation flow. This is true of North American/European skilled immigrants for all skill-level...
Tipo: Conference Paper or Presentation Palavras-chave: Canada; Endogenous technological change; Innovation; National ideas; Production function; Patents; Skilled immigrants; Labor and Human Capital.
Ano: 2008 URL: http://purl.umn.edu/6504
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Nonconventional Technology for Agricultural Development in Developing Countries AgEcon
Soliman, Ibrahim.
This paper concerns the economic assessment of a nonconventional technology to provide a cheap food and/or feed for many developing countries, using wasted resources, i.e. coastal arid areas irrigated directly with seawater to grow a halophyte crop(Salicornia-sos-7). It was cultivated for two successive years in Kuwait. The analysis showed that the harvested yield was 20 tons per hectare, which provided 12.42 MT of straw for sale and 1.7 MT of oil seeds for processing. Processed seeds of 1-hectare provide 425 kg of food oil and 1.1 MT of feed meal.Under Kuwait conditions, on per hectare basis, the total costs of production( fixed &variable costs)were $3088. However,simulation of this technology under a conventional developing country like Egypt with...
Tipo: Article Palavras-chave: Halophyte Crops; Seawater irrigation system; Salicornia as oil seeds crop; Scaling Up the experiments; Profit Margin; Production function; Least cost Ration; Sheep fattning; Agribusiness; Community/Rural/Urban Development; Crop Production/Industries; Land Economics/Use; Livestock Production/Industries; Production Economics; Research and Development/Tech Change/Emerging Technologies; Research Methods/ Statistical Methods; Resource /Energy Economics and Policy.
Ano: 1991 URL: http://purl.umn.edu/119721
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Ozone Externalities on Crop Production: Insights from UK Farm Level Data AgEcon
Neeliah, Harris; Shankar, Bhavani.
Tropospheric ozone is an air pollutant thought to reduce crop yields across Europe. Much experimental scientific work has been completed or is currently underway to quantify yield effects at ambient ozone levels. In this research, we seek to directly evaluate whether such effects are observed at the farm level. We use both primal (production function) as well as dual (profit function) methods, with ozone as a fixed input, to explore the extent to which output and profits are affected by ozone in the UK. A panel dataset on UK farms is intersected with spatial data on ozone, and panel data production and profit function estimation methods are used. The production function does predict a statistically significant negative effect of ozone on wheat yields at...
Tipo: Conference Paper or Presentation Palavras-chave: Ozone; Wheat; Crop production; Production function; Profit function; Crop Production/Industries; Resource /Energy Economics and Policy; Q4; P2.
Ano: 2005 URL: http://purl.umn.edu/24659
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Production function estimation in Stata using the Olley and Pakes method AgEcon
Yasar, Mahmut; Raciborski, Rafal; Poi, Brian P..
Productivity is often computed by approximating the weighted sum of the inputs from the estimation of the Cobb–Douglas production function. Such estimates, however, may suffer from simultaneity and selection biases. Olley and Pakes (1996, Econometrica 64: 1263–1297) introduced a semiparametric method that allows us to estimate the production function parameters consistently and thus obtain reliable productivity measures by controlling for such biases. This study first reviews this method and then introduces a Stata command to implement it. We show that when simultaneity and selection biases are not controlled for, the coefficients for the variable inputs are biased upward and the coefficients for the fixed inputs are biased downward.
Tipo: Article Palavras-chave: Opreg; Levpet; Production function; Bias; Simultaneity; Research Methods/ Statistical Methods.
Ano: 2008 URL: http://purl.umn.edu/122587
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Productivity and Economic Growth in Tunisian Agriculture: An Empirical Evidence AgEcon
Dhehibi, Boubaker; Lachaal, Lassaad.
This paper analyse the patterns of productivity and economic growth in the Tunisian agriculture during the 1961–2000. Results indicated that agriculture output growth where high in both the 1961–1970 and the 1971–1980 periods but decreased during the 1991–2000 period. Average output growth exceeded 6% during the 1981–1990 period, the average output growth during 1991–2000 had fallen to 4%. Over the whole period, capital was the most important contributor to output growth and labour is considered as the least significant contributor to economic growth. Total factor productivity contribution to output growth decreased from 4.64% in 1961–1970 to 2.86% in 1971–1980. In contrast, this contribution increased in 1981-1990 to close the 4.38%. In the last period,...
Tipo: Conference Paper or Presentation Palavras-chave: Production function; Translog; Agriculture; TFP; Tunisia; International Development; Productivity Analysis; C8; O13; O14.
Ano: 2006 URL: http://purl.umn.edu/25707
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Productivity and farm size in Australian agriculture: reinvestigating the returns to scale AgEcon
Sheng, Yu; Zhao, Shiji; Nossal, Katarina.
Higher productivity among large farms is often assumed to be a result of increasing returns to scale. However, using farm-level data for the Australian broadacre industry, it was found that constant or mildly decreasing returns to scale is more typical. On examining the monotonic change in marginal input returns as farm operating size increases, it was found that large farms achieve higher productivity through changes in production technology rather than through changes in scale. The results highlight the disparity between ‘returns to scale’ and ‘returns to size’ in Australian agriculture. They also suggest that improving productivity in smaller farms would depend more on their ability to access advanced technologies than their ability to simply expand....
Tipo: Conference Paper or Presentation Palavras-chave: Returns to scale; Returns to size; Production function; Technology progress; Structural adjustment; Australian agriculture; Agricultural and Food Policy.
Ano: 2011 URL: http://purl.umn.edu/100711
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Resposta da alfafa a diversas disponibilidades de agua. Repositório Alice
CUNHA, G.R. da; BERGAMASCHI, H.; PAULA, J.R.F. de; SAIBRO, J.C. de.
Foi conduzido um estudo com alfafa (Medicago sativa L.), cv. Crioula,semeada em junho de 1989 (0,3 m entre linhas), na EEA-UFRGS, em Eldorado do Sul (30.5'S,51.39'W e 46 m de altitude), visando avaliar a resposta da cultura a agua e sua interacao com a disponibilidade de fosforo (P). Foi usado o sistema de aspersao em linha, envolvendo seis laminas de agua (chuva + irrigacao) e tres doses de P (uma, duas e quatro vezes a recomendada, de acordo com a analise de solo). O rendimento total de materia seca (MS) de quatro cortes do periodo de primavera-verao, de outubro de 1989 a marco de 1990, foi significativamente afetado somente pela espessura da lamina de agua. O rendimento total de MS relacionado com a maior espessura da lamina de agua (716,9 mm) foi 125%...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Deficit hidrico; Funcao de producao; Irrigacao; Medicago sativa; Sistema de aspersao em linha; Fertilizacao com fosforo; Hydric deficit; Production function; Irrigation; Line-source sprinkler system; Phosphorus fertilization.
Ano: 1998 URL: http://www.alice.cnptia.embrapa.br/handle/doc/97637
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Returns to Scale of Production Function: Pooled, Within and Between Quantile Regression Approach AgEcon
Reimbaeva, Maya; Shaik, Saleem; Mishra, Ashok K..
Tipo: Conference Paper or Presentation Palavras-chave: Production function; Pooled; Between and Within Quantile Regression; Panel data; Production Economics; Research Methods/ Statistical Methods.
Ano: 2010 URL: http://purl.umn.edu/56563
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