Sabiia Seb
PortuguêsEspañolEnglish
Embrapa
        Busca avançada

Botão Atualizar


Botão Atualizar

Ordenar por: RelevânciaAutorTítuloAnoImprime registros no formato resumido
Registros recuperados: 57
Primeira ... 123 ... Última
Imagem não selecionada

Imprime registro no formato completo
A SYSTEMS APPROACH FOR EVALUATING ON-FARM SITE-SPECIFIC MANAGEMENT TRIALS: A CASE STUDY WITH VARIABLE RATE MANURE AND CROP QUALITY RESPONSE TO INPUTS AgEcon
Lambert, Dayton M.; Lowenberg-DeBoer, James; Malzer, Gary L..
Site-specific application of manure has the potential to improve crop production and environmental quality. If manure is applied where it is needed, in the quantity required by the crop, over application, with attendant runoff and leaching problems can be reduced. To implement this approach growers need site-specific crop response information. Increasing availability of site-specific yield information offers a way to estimate such crop responses. The objective of this study is to develop a methodology for estimating site-specific response of corn and soybeans to manure given soil test information, and to use that methodology to analyze an on-farm manure management trial conducted near Sleepy Eye, Minnesota. Both quantity and quality of the crop is...
Tipo: Conference Paper or Presentation Palavras-chave: Research Methods/ Statistical Methods.
Ano: 2004 URL: http://purl.umn.edu/20091
Imagem não selecionada

Imprime registro no formato completo
A SYSTEMS APPROACH INCORPORATING SOIL TEST INFORMATION INTO SITE-SPECIFIC MANURE MANAGEMENT RECOMMENDATIONS AgEcon
Lambert, Dayton M.; Malzer, Gary L.; Lowenberg-DeBoer, James.
Replaced with revised version of paper 04/28/04.
Tipo: Working or Discussion Paper Palavras-chave: Crop Production/Industries.
Ano: 2003 URL: http://purl.umn.edu/28623
Imagem não selecionada

Imprime registro no formato completo
A TWO-STEP ESTIMATOR FOR A SPATIAL LAG MODEL OF COUNTS: THEORY, SMALL SAMPLE PERFORMANCE AND AN APPLICATION AgEcon
Lambert, Dayton M.; Brown, Jason P.; Florax, Raymond J.G.M..
Several spatial econometric approaches are available to model spatially correlated disturbances in count models, but there are at present no structurally consistent count models incorporating spatial lag autocorrelation. A two-step, limited information maximum likelihood estimator is proposed to fill this gap. The estimator is developed assuming a Poisson distribution, but can be extended to other count distributions. The small sample properties of the estimator are evaluated with Monte Carlo experiments. Simulation results suggest that the spatial lag count estimator achieves gains in terms of bias over the aspatial version as spatial lag autocorrelation and sample size increase. An empirical example deals with the location choice of single-unit start-up...
Tipo: Working or Discussion Paper Palavras-chave: Count model; Location choice; Manufacturing; Poisson; Spatial econometrics; Community/Rural/Urban Development; Land Economics/Use; Research and Development/Tech Change/Emerging Technologies; C21; C25; D21; R12; R30.
Ano: 2010 URL: http://purl.umn.edu/59780
Imagem não selecionada

Imprime registro no formato completo
Adoption and Abandonment of Precision Soil Sampling in Cotton Production AgEcon
Walton, Jonathan C.; Roberts, Roland K.; Lambert, Dayton M.; Larson, James A.; English, Burton C.; Larkin, Sherry L.; Martin, Steven W.; Marra, Michele C.; Paxton, Kenneth W.; Reeves, Jeanne M..
Technology adoption in precision agriculture has received considerable attention, while abandonment has received little. Our objective was to identify factors motivating adoption and abandonment of precision soil sampling in cotton. Results indicate younger producers who farmed more cotton area, owned more of their cropland, planted more non-cotton area, used a computer, or used a Personal Digital Assistant (PDA) were more likely to adopt precision soil sampling. Those with more cotton area or who owned livestock were more likely to abandon, while those who used precision soil sampling longer, used a PDA, or used variable-rate fertilizer application were less likely to abandon.
Tipo: Conference Paper or Presentation Palavras-chave: Crop Production/Industries.
Ano: 2008 URL: http://purl.umn.edu/6215
Imagem não selecionada

Imprime registro no formato completo
Adoption and Abandonment of Precision Soil Sampling in Cotton Production AgEcon
Walton, Jonathan C.; Lambert, Dayton M.; Roberts, Roland K.; Larson, James A.; English, Burton C.; Larkin, Sherry L.; Martin, Steven W.; Marra, Michele C.; Paxton, Kenneth W.; Reeves, Jeanne M..
Adoption of precision agriculture technology has arrived considerable attention, but abandonment has received little. This paper identified factors motivating adoption and abandonment of precision soils sampling in cotton. Younger producers who farmed more cotton area, owned more of their cropland, planted more non-cotton area, or used a computer were more likely to adopt precision soil sampling. Those with more cotton area or who owned livestock were more likely to abandon, while those who used precision soil sampling longer, or used variable-rate fertilizer application were less likely to abandon precision soil sampling.
Tipo: Journal Article Palavras-chave: Abandonment; Adoption; Cotton; Precision; Agriculture; Soil sampling; Southeastern United States; Crop Production/Industries.
Ano: 2008 URL: http://purl.umn.edu/46556
Imagem não selecionada

Imprime registro no formato completo
ADOPTION, PROFITABILITY, AND MAKING BETTER USE OF PRECISION FARMING DATA AgEcon
Lambert, Dayton M.; Lowenberg-DeBoer, James; Griffin, Terry W.; Peone, J.; Payne, Tim; Daberkow, Stan G..
Precision agriculture (PA) technology has been on the market for over ten years. Global Positioning Systems (GPS), Geographic Information Systems (GIS), yield monitors, variable rate technologies (VRT) and other spatial management technologies are being used by farmers worldwide, but questions remain about the profitability of the technology and its future. This paper summarizes: 1) data on adoption of PA technology worldwide, 2) review of PA economics studies and 3) efforts to make better use of yield monitor and other sensor data in crop management. The adoption estimates are based on reports by an international network of collaborators. This paper draws on USDA ARMS data to update U.S. PA adoption numbers. The PA profitability summary goes beyond...
Tipo: Working or Discussion Paper Palavras-chave: Agribusiness.
Ano: 2004 URL: http://purl.umn.edu/28615
Imagem não selecionada

Imprime registro no formato completo
An Application of Spatial Poisson Models to Manufacturing Investment Location Analysis AgEcon
Lambert, Dayton M.; McNamara, Kevin T.; Garrett, Megan I..
The influence product markets, agglomeration, labor, infrastructure, and government fiscal attributes had on manufacturing investment flows in Indiana between 2000 and 2004 were estimated using Poisson regression, geographically weighted regression, and a spatial general linear model. Counties with access to urbanization economies, product markets, available labor, a high-quality workforce, and transport infrastructure were more likely to attract manufacturing investment. These effects were magnified to some extent when inter-county spatial effects were modeled. The distributional assumptions of the spatial models are different, but both methods are useful for understanding the spatial context of the factors influencing manufacturing investment flows.
Tipo: Journal Article Palavras-chave: Geographically weighted regression; Location determinants; Location theory; Manufacturing site selection; Poisson spatial generalized linear model; Agribusiness; Industrial Organization; Productivity Analysis; R1; R3.
Ano: 2006 URL: http://purl.umn.edu/43752
Imagem não selecionada

Imprime registro no formato completo
ANALYSIS OF GOVERNMENT FARM SUBSIDIES ON FARMLAND CASH RENTAL RATES USING A FIXED EFFECT SPATIAL DISTRIBUTED LAG MODEL AND A TRANSLOG COST MODEL AgEcon
Lambert, Dayton M.; Griffin, Terry W..
The objective of this study is to examine how factors such as government payments, soil productivity ratings, commodity selling price, corn and soybean production, and spatial attributes affect cash rental rates. Baseline estimates of the effects of government payments on cash rents are determined using a fixed effect, distributed lag model. The results of this model are compared to a distributed lag model that incorporates spatial effects. A second model estimates the impact of government subsides on farm cost structure. This is accomplished estimating a fixed effect, translog cost function that also incorporates spatial effects. The data used in the analysis is the Illinois Farm Business Farm Management (FBFM) Economic Management Analysis (EMA),...
Tipo: Conference Paper or Presentation Palavras-chave: Farm Management.
Ano: 2004 URL: http://purl.umn.edu/19977
Imagem não selecionada

Imprime registro no formato completo
BANDWIDTH SELECTION FOR SPATIAL HAC AND OTHER ROBUST COVARIANCE ESTIMATORS AgEcon
Lambert, Dayton M.; Florax, Raymond J.G.M.; Cho, Seong-Hoon.
This research note documents estimation procedures and results for an empirical investigation of the performance of the recently developed spatial, heteroskedasticity and autocorrelation consistent (HAC) covariance estimator calibrated with different kernel bandwidths. The empirical example is concerned with a hedonic price model for residential property values. The first bandwidth approach varies an a priori determined plug-in bandwidth criterion. The second method is a data driven cross-validation approach to determine the optimal neighborhood. The third approach uses a robust semivariogram to determine the range over which residuals are spatially correlated. Inference becomes more conservative as the plug-in bandwidth is increased. The data-driven...
Tipo: Working or Discussion Paper Palavras-chave: Spatial HAC; Semivariogram; Bandwidth; Hedonic model; Community/Rural/Urban Development; Demand and Price Analysis; Land Economics/Use; Research Methods/ Statistical Methods; C13; C31; R21.
Ano: 2008 URL: http://purl.umn.edu/44258
Imagem não selecionada

Imprime registro no formato completo
BANDWIDTH SELECTION FOR SPATIAL HAC AND OTHER ROBUST COVARIANCE ESTIMATORS AgEcon
Lambert, Dayton M.; Florax, Raymond J.G.M.; Cho, Seong-Hoon.
This research note documents estimation procedures and results for an empirical investigation of the performance of the recently developed spatial, heteroskedasticity and autocorrelation consistent (HAC) covariance estimator calibrated with different kernel bandwidths. The empirical example is concerned with a hedonic price model for residential property values. The first bandwidth approach varies an a priori determined plug-in bandwidth criterion. The second method is a data driven cross-validation approach to determine the optimal neighborhood. The third approach uses a robust semivariogram to determine the range over which residuals are spatially correlated. Inference becomes more conservative as the plug-in bandwidth is increased. The data-driven...
Tipo: Working or Discussion Paper Palavras-chave: Spatial HAC; Semivariogram; Bandwidth; Hedonic model; Research Methods/ Statistical Methods; C13; C31; R21.
Ano: 2008 URL: http://purl.umn.edu/45964
Imagem não selecionada

Imprime registro no formato completo
Business Establishment Growth in the Appalachian Region, 2000-2007: An Application of Smooth Transition Spatial Process Models AgEcon
Xu, Wan; Lambert, Dayton M..
Business establishment growth in the Appalachian region (2000–2007) was regressed on industry sector composition controlling for demographic, physical, and economic determinants. We test the hypothesis that local response to growth determinants is geographically heterogeneous using Smooth Transition spatial process models. This class of models exhibiting endogenous regime switching behavior provides another tool for exploring the spatially heterogeneous effects of local determinants on economic growth.
Tipo: Journal Article Palavras-chave: Appalachia; Business establishment growth; Smooth transition models; Spatial processes; Community/Rural/Urban Development; C21; C51; O47; R11.
Ano: 2011 URL: http://purl.umn.edu/113517
Imagem não selecionada

Imprime registro no formato completo
Conservation Reserve Program Participation and Acreage Enrollment of Working Farms AgEcon
Lambert, Dayton M.; Sullivan, Patrick.
Among Conservation Reserve Program (CRP) participants, there is a distinction between farm households using the program to ease out of farming and those using the program to augment production receipts. We find evidence that factors other than farm profitability and environmental factors may influence program participation of farmers who continue agricultural production. Program payments and farm size positively correlate with the amount of land enrolled in the CRP, and characteristics of participants in land retirement and working-lands CRP components are similar.
Tipo: Conference Paper or Presentation Palavras-chave: Environmental Economics and Policy.
Ano: 2006 URL: http://purl.umn.edu/21361
Imagem não selecionada

Imprime registro no formato completo
Conservation-Compatible Practices and Programs: Who Participates? AgEcon
Lambert, Dayton M.; Sullivan, Patrick; Claassen, Roger; Foreman, Linda F..
In recent years, the Federal Government has increased its emphasis on conservation programs that reward good stewardship on working farmland. This report examines the business, operator, and household characteristics of farms that have adopted certain conservation-compatible practices, with and without financial assistance from government conservation programs. The analysis finds that characteristics of the farm operator and household, in addition to the characteristics of the farm business, are associated with both the likelihood that a farmer will adopt certain conservation-compatible practices and the degree to which the farmer participates in different types of conservation programs. For example, operators of small farm operations and operators not...
Tipo: Report Palavras-chave: Conservation programs; Conservation-compatible management practices; Conservation structures; Farm households; Conservation Reserve Program; Environmental Quality Incentives Program; Land Economics/Use.
Ano: 2006 URL: http://purl.umn.edu/7255
Imagem não selecionada

Imprime registro no formato completo
Dynamic Optimization of Fertilizer Application with Carryover and Runoff AgEcon
Zhou, Xia (Vivian); Clark, Christopher D.; Lambert, Dayton M..
The Economics of fertilizer application has been an interesting issue in regard to crop production (Kennedy et al., 1973). Understanding the temporal dynamics complicates the issue along two dimensions: fertilizer carryover and fertilizer runoff. Fertilizer carryover measures the amount of fertilizer applied in the previous period that is available for crops in current growing period (Kennedy et al., 1973). Fertilizer runoff refers to fertilizer leaving the ground and flowing into water bodies. Thus, the optimal quantity of fertilizer to be applied in the current period depends on the amount of previous application, runoff, and carryover. Because fertilizer carryover and runoff makes optimization of application a complicated intertemporal problem, static...
Tipo: Conference Paper or Presentation Palavras-chave: Dynamic Optimization; Fertilizer Application; Carryover; And Runoff; Crop Production/Industries; Land Economics/Use; Production Economics; Resource /Energy Economics and Policy.
Ano: 2011 URL: http://purl.umn.edu/103442
Imagem não selecionada

Imprime registro no formato completo
Estimating Travel Cost Model: Spatial Approach AgEcon
Kim, Seung Gyu; Bowker, James Michael; Cho, Seong-Hoon; Lambert, Dayton M.; English, Donald B.K.; Starbuck, C. Meghan.
Tipo: Working or Discussion Paper Palavras-chave: Travel cost model; Spatial analysis; Environmental Economics and Policy.
Ano: 2010 URL: http://purl.umn.edu/61774
Imagem não selecionada

Imprime registro no formato completo
Ethanol Plant Location Determinants and County Comparative Advantage AgEcon
Lambert, Dayton M.; Wilcox, Michael D.; English, Alicia; Stewart, Lance A..
The location of ethanol plants is determined by infrastructure, product and input markets, fiscal attributes of local communities, and state and federal incentives. This empirical analysis uses probit regression along with spatial clustering methods to analyze investment activity of ethanol plants at the county level for the lower U.S. 48 states from 2000 to 2007. The availability of feedstock dominates the site selection decision. Other factors, such as access to navigable rivers or railroads, product markets, producer credit and excise tax exemptions, and methyl tertiary-butyl ether bans provided some counties with a comparative advantage in attracting ethanol plants.
Tipo: Journal Article Palavras-chave: Cluster analysis; Comparative advantage; Ethanol production; Location model; Community/Rural/Urban Development; Environmental Economics and Policy; Political Economy; R1; R3.
Ano: 2008 URL: http://purl.umn.edu/45511
Imagem não selecionada

Imprime registro no formato completo
Exploring Farm Business and Household Expenditure Patterns and Community Linkages AgEcon
Lambert, Dayton M.; Sullivan, Patrick; Wojan, Timothy R..
Farm operators are an integral part of some rural economies. The businesses they operate often hire seasonal and full-time employees and purchase goods and services from local farm implement dealers, input suppliers, and financial institutions. Farm household spending on food, furniture and appliances, trucks and automobiles, and a range of consumer goods also support local jobs and retail businesses in some communities. Based on the 2002 agricultural census and the 2004 Agricultural Resource Management Survey, this paper explores the linkages between farm household/ business expenditures and local communities.
Tipo: Conference Paper or Presentation Palavras-chave: Farm business expenditures; Farm household spending; Employment; Community linkage; Consumer/Household Economics; Farm Management; Community/Rural/Urban Development.
Ano: 2008 URL: http://purl.umn.edu/6367
Imagem não selecionada

Imprime registro no formato completo
Extreme coefficients in Geographically Weighted Regression and their effects on mapping AgEcon
Cho, Seong-Hoon; Lambert, Dayton M.; Kim, Seung Gyu; Jung, Suhyun.
This study deals with the issue of extreme coefficients in geographically weighted regression (GWR) and their effects on mapping coefficients using three datasets with different spatial resolutions. We found that although GWR yields extreme coefficients regardless of the resolution of the dataset or types of kernel function, 1) the GWR tends to generate extreme coefficients for less spatially dense datasets, 2) coefficient maps based on polygon data representing aggregated areal units are more sensitive to extreme coefficients, and 3) coefficient maps using bandwidths generated by a fixed calibration procedure are more vulnerable to the extreme coefficients than adaptive calibration.
Tipo: Conference Paper or Presentation Palavras-chave: Extreme coefficient; Fixed and adaptive calibrations; Geographically weighted regression; Mapping; Research Methods/ Statistical Methods.
Ano: 2009 URL: http://purl.umn.edu/49117
Imagem não selecionada

Imprime registro no formato completo
Factors Affecting Direct and Indirect Energy Use in U.S. Corn Production AgEcon
Musser, Wesley N.; Lambert, Dayton M.; Daberkow, Stan G..
The recent volatility of energy prices has numerous policy implications for agriculture. A better understanding of the factors associated with energy consumption as related to crop production management decisions and technology use may provide insight about how producers might respond to program or market incentives targeting energy use in particular, and soil and water conservation in general. Adoption of minimum tillage could reduce erosion and improved fertilizer management practices could reduce nitrogen runoff. Energy costs may be reduced with adoption of reduced tillage technology, improved drying and irrigation systems, or more careful attention to the application and timing of fertilizers.
Tipo: Conference Paper or Presentation Palavras-chave: Energy; Fuel; Nitrogen; Farm management; Technology; Crop Production/Industries; Q12; Q40.
Ano: 2006 URL: http://purl.umn.edu/21063
Imagem não selecionada

Imprime registro no formato completo
Factors Affecting Producer Participation in State-Sponsored Marketing Programs By Fruit and Vegetable Growers in Tennessee AgEcon
Davis, James A.; Velandia, Margarita M.; Clark, Christopher D.; Lambert, Dayton M.; Jensen, Kimberly L.; Wilcox, Michael D.; Wszelaki, Annette.
State programs promoting agricultural products have proliferated in response to increased consumer interest in locally grown foods. Tennessee, for example, currently has two state-sponsored programs promoting Tennessee agricultural products. This study examines the factors associated with fruit and vegetable farmer participation in these programs using mean comparisons and bivariate probit regression. Results suggest that farmer participation in these programs was associated with operation size, percentage of income from farming, percentage of annual sales from fresh produce, and attendance to University Extension educational events. These results should interest individuals attempting to increase producer participation in these types of programs.
Tipo: Presentation Palavras-chave: State-sponsored marketing program; Fruit and vegetable marketing; Tennessee producer participation; Bivariate probit regression.JEL: Q13; Q18.; Agribusiness; Agricultural and Food Policy; Marketing; Q13; Q18..
Ano: 2012 URL: http://purl.umn.edu/123923
Registros recuperados: 57
Primeira ... 123 ... Última
 

Empresa Brasileira de Pesquisa Agropecuária - Embrapa
Todos os direitos reservados, conforme Lei n° 9.610
Política de Privacidade
Área restrita

Embrapa
Parque Estação Biológica - PqEB s/n°
Brasília, DF - Brasil - CEP 70770-901
Fone: (61) 3448-4433 - Fax: (61) 3448-4890 / 3448-4891 SAC: https://www.embrapa.br/fale-conosco

Valid HTML 4.01 Transitional