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	Provedor de dados AgEcon (18) Autor Gocht, Alexander (3) Ishdorj, Ariun (3) Jensen, Helen H. (3) Roder, Norbert (2) Balcombe, Kelvin George (1) Burton, Michael P. (1) Canova, Fabio (1) Caracciolo, Francesco (1) Crepinsek, Mary Kay (1) Dorfman, Jeffrey H. (1) Fragoso, Rui Manuel de Sousa (1) Ghazalian, Pascal L. (1) Gotor, Elisabetta (1) Heckelei, Thomas (1) Holloway, Garth J. (1) Howitt, Richard E. (1) Huettel, Silke (1) Jansson, Torbjorn (1) Jongeneel, Roelof A. (1) Karali, Berna (1) Mais... Palavra-chave C11 (18) Agricultural and Food Policy (6) Food Consumption/Nutrition/Food Safety (5) Research Methods/ Statistical Methods (5) C34 (4) C81 (4) D12 (4) Q12 (4) Q15 (4) Agribusiness (3) Bayesian econometrics (3) C61 (3) Down scaling (3) Highest Posterior Density estimator (HPD) (3) Q18 (3) RAUMIS (3) AIDS model (2) Censored (2) Cereals (2) Demand and Price Analysis (2) Mais... Tipo do documento Conference Paper or Presentation (13) Journal Article (2) Working or Discussion Paper (2) Presentation (1) Ano 2012 (1) 2011 (5) 2010 (3) 2009 (2) 2008 (3) 2005 (2) 2002 (1) 2001 (1) Mais... País United States (18) Idioma Inglês (18)		Ordenar por:  Relevância Autor Título Ano Registros recuperados: 18 Primeira ... 1 ... Última A BAYESIAN ALTERNATIVE TO GENERALIZED CROSS ENTROPY SOLUTIONS FOR UNDERDETERMINED ECONOMETRIC MODELS AgEcon Heckelei, Thomas; Mittelhammer, Ronald C.; Jansson, Torbjorn. This paper presents a Bayesian alternative to Generalized Maximum Entropy (GME) and Generalized Cross Entropy (GCE) methods for deriving solutions to econometric models represented by underdetermined systems of equations. For certain types of econometric model specifications, the Bayesian approach provides fully equivalent results to GME-GCE techniques. However, in its general form, the proposed Bayesian methodology allows a more direct and straightforwardly interpretable formulation of available prior information and can reduce significantly the computational effort involved in finding solutions. The technique can be adapted to provide solutions in situations characterized by either informative or uninformative prior information. Tipo: Working or Discussion Paper Palavras-chave: Underdetermined Equation Systems; Maximum Entropy; Bayesian Priors; Structural Estimation; Calibration; Research Methods/ Statistical Methods; C11; C13; C51. Ano: 2008 URL: http://purl.umn.edu/56973 A minimum cross entropy model to generate disaggregated agricultural data at the local level AgEcon Xavier, Antonio; Martins, Maria de Belem Costa Freitas; Fragoso, Rui Manuel de Sousa. This work presents an entropy approach to disaggregate agricultural data at a local level. It comprises two different steps. In a first one, an information prior at disaggregated level based on experts’ opinions, available cartography of land use and biophysical data is created. In a second step, it’s used a minimum cross entropy process in order to manage these information inputs and to guaranty a solution compatible with all the different restrictions. The model was applied to the region of Algarve in the year of 1999, in order to disaggregate the data at the pixel and county level. Results show that the model was able to provide some satisfactory results since the estimated values obtained for the different areas revealed a good approximation to the... Tipo: Conference Paper or Presentation Palavras-chave: Minimum cross entropy; Data disaggregation; Local level; Algarve; Agricultural policies; Agricultural and Food Policy; C11; C81; Q15; R14. Ano: 2011 URL: http://purl.umn.edu/98991 Bayesian Estimation of a Censored AIDS Model for Whole Grain Products AgEcon Ishdorj, Ariun; Jensen, Helen H.. When using household-level data in examining consumer's demand it is common to find that consumers purchase only a subset of the available goods, setting the demand for the remaining goods to zero. Ignoring such censoring of the dependent variables in the estimation can lead to biased parameter estimates. In this paper we investigate the household's demand for six types of whole grain and non-whole grain breakfast cereals and products using a censored Almost Ideal Demand System (AIDS) and estimate the parameters of the demand system via Bayesian methods. Using 2006 ACNielsen Homescan data we find that demand for whole grain and non-whole grain ready-to-eat cereals is less responsive to changes in prices; demand for whole-grain bars and non-whole grain hot... Tipo: Conference Paper or Presentation Palavras-chave: AIDS model; Bayesian econometrics; Censored; Cereals; Whole grains; Demand and Price Analysis; C11; C34; D12. Ano: 2008 URL: http://purl.umn.edu/6075 Best Management Practices to Enhance Water Quality: Who is Adopting Them? AgEcon Ghazalian, Pascal L.; Larue, Bruno; West, Gale E.. This study investigates the determinants affecting producers’ adoption of some Best Management Practices (BMPs). Priors about the signs of certain variables are explicitly accounted for by testing for inequality restrictions through importance sampling. Education, gender, age, and on-farm residence are found to have significant effects on the adoption of some BMPs. Farms with larger animal production are more apt to implement manure management practices, crop rotation, and riparian buffer strips. Also, farms with larger cultivated acres are more inclined to implement herbicide control practices, crop rotation, and riparian buffer strips. Belonging to an agro-environment club has a positive impact for most BMPs. Tipo: Journal Article Palavras-chave: Adoption; Bayesian analysis; Best management practices; Priors; Runoff; Water quality; Agribusiness; Agricultural and Food Policy; Crop Production/Industries; Farm Management; Food Consumption/Nutrition/Food Safety; Land Economics/Use; Livestock Production/Industries; Q12; Q25; C11. Ano: 2009 URL: http://purl.umn.edu/56655 Children’s Consumption of Fruits and Vegetables: Do School Environment and Policies Affect Choice in School Meals? AgEcon Ishdorj, Ariun; Crepinsek, Mary Kay; Jensen, Helen H.. Considering most children spend a majority of their weekdays at school and, on average, obtain more than one-third of their daily caloric intake from meals consumed at school during the school year, school is a natural place to implement nutrition policies that would help develop healthy eating habits and improve health and well-being of children. At the same time, local school meal policies may influence what foods are offered and how the foods are prepared. In this regard, the U.S. Department of Agriculture’s (USDA) two school meal programs can play an important role in children’s diets and food habit formation and thus positively influence children’s health. The focus of our research is children’s intakes of fruits and vegetables by location of... Tipo: Presentation Palavras-chave: Food Assistance; Fruits and Vegetables; School Meals; Endogeneity; Censoring; Food Consumption/Nutrition/Food Safety; C11; C34; C36. Ano: 2012 URL: http://purl.umn.edu/123534 DEMAND FOR BREAKFAST CEREALS: WHOLE GRAINS GUIDANCE AND FOOD CHOICE AgEcon Ishdorj, Ariun; Jensen, Helen H.. When using household-level data to examine consumer demand it is common to find that consumers purchase only a subset of the available goods, setting the demand for the remaining goods to zero. Ignoring such censoring of the dependent variables can lead to estimators with poor statistical properties and estimates that lead to poor policy decisions. In this paper we investigate household demand for four types of breakfast cereals, such as whole grain ready-to-eat, non-whole grain ready-to-eat, whole grain hot and non-whole grain hot cereals, using a censored Al- most Ideal Demand System (AIDS) and estimate the parameters of the model via Bayesian methods. Using household level scanner data (ACNielsen Homescan) we find that demand for all types of breakfast... Tipo: Conference Paper or Presentation Palavras-chave: AIDS model; Bayesian econometrics; Censored; Cereals; Whole grains; Agricultural and Food Policy; Consumer/Household Economics; Demand and Price Analysis; Food Consumption/Nutrition/Food Safety; Food Security and Poverty; Health Economics and Policy; C11; C34; D12. Ano: 2010 URL: http://purl.umn.edu/116445 Do Farmers Hedge Optimally or by Habit? A Bayesian Partial-Adjustment Model of Farmer Hedging AgEcon Dorfman, Jeffrey H.; Karali, Berna. Hedging is one of the most important risk management decisions that farmers make and has a potentially large role in the level of profit eventually earned from farming. Using panel data from a survey of Georgia farmers that recorded their hedging decisions for 4 years on four crops, we examine the role of habit, demographics, farm characteristics, and information sources on the hedging decisions made by 57 different farmers. We find that the role of habit varies widely and that estimation of a single habit effect suffers from aggregation bias. Thus, modeling farmer-level heterogeneity in the examination of habit and hedging is crucial. Tipo: Journal Article Palavras-chave: Bayesian econometrics; Habit formation; Hedging decisions; Information sources; Agribusiness; Agricultural Finance; Farm Management; Financial Economics; Labor and Human Capital; Production Economics; Productivity Analysis; Research Methods/ Statistical Methods; C11; Q12; Q14. Ano: 2010 URL: http://purl.umn.edu/100519 Economic Consequences of Biological Variation: The Case of Mycoplasma in Swine Herds AgEcon Otto, Lars. We present an economic decision support model, based on a Bayesian network, for Mycoplasma infection in slaughter swine production. The model describes the various risk factors for Mycoplasma infection and their interactions. This leads to a stochastic determination of the consequences of productivity factors, and this again results in stochastic economic consequences when changing the risk factors or engaging in control arrangements. We use the model to calculate how estimated prevalence and level of Mycoplasma changes when we gather evidence from various veterinarian examinations, and we show how this influences the distribution of the economic results of a change in strategy to fight Mycoplasma. One result is that the profitability in fighting... Tipo: Conference Paper or Presentation Palavras-chave: Decision support system; Bayesian network; Pig; Mycoplasma; Livestock Production/Industries; C11; D81; Q12. Ano: 2005 URL: http://purl.umn.edu/24458 Household food expenditures in the United States: A Bayesian MCMC approach to censored equation systems AgEcon Kasteridis, Panagiotis P.; Yen, Steven T.. We apply a Bayesian Markov Chain Monte Carlo (MCMC) technique, along with data augmentation to accommodate censoring in the dependent variables, to the estimation of a large expenditure system of food expenditures. Our finding of significant error covariance estimates justifies estimation of the system in improving statistical efficiency. Income, household composition, regions and other socio-demographic variables are found to play significant roles in determining household food expenditures. Tipo: Conference Paper or Presentation Palavras-chave: Bayesian MCMC; Censored equation system; Consumer Expenditure Survey; Food Consumption/Nutrition/Food Safety; C11; C34; D12; C11; C34; D12. Ano: 2010 URL: http://purl.umn.edu/61763 Impact of Income on Calorie and Nutrient Intakes: A Cross-Country Analysis AgEcon Salois, Matthew J.; Tiffin, J. Richard; Balcombe, Kelvin George. The relationship between income and nutrient intake is explored. Nonparametric, panel, and quantile regressions are used. Engle curves for calories, fat, and protein are approximately linear in logs with carbohydrate intakes exhibiting diminishing elasticities as incomes increase. Elasticities range from 0.10 to 0.25, with fat having the highest elasticities. Countries in higher quantiles have lower elasticities than those in lower quantiles. Results predict significant cumulative increases in calorie consumption which are increasingly composed of fats. Though policies aimed at poverty alleviation and economic growth may assuage hunger and malnutrition, they may also exacerbate problems associated with obesity. Tipo: Conference Paper or Presentation Palavras-chave: Calorie and nutrient consumption; Food and nutrition policy; Income elasticities; Nonparametric; Panel; Quantile regression.; Agricultural and Food Policy; Food Consumption/Nutrition/Food Safety; Food Security and Poverty; International Development; Research Methods/ Statistical Methods; C11; C14; C21; C23; O10; O47; Q18. Ano: 2011 URL: http://purl.umn.edu/103647 Impact of the EU Milk Quota on Structural Change in the Dairy Sectors of Germany and The Netherlands AgEcon Huettel, Silke; Jongeneel, Roelof A.. Tipo: Conference Paper or Presentation Palavras-chave: Markov Chain; Milk Quota Scheme; Structural Change; Agribusiness; Agricultural and Food Policy; O11; C11. Ano: 2009 URL: http://purl.umn.edu/50943 MUNICIPALITY DISAGGREGATION OF GERMAN'S AGRICULTURAL SECTOR MODEL RAUMIS AgEcon Roeder, Norbert; Gocht, Alexander. Since several decades the RAUMIS modelling system is applied for policy impact assessments to measure the impact of agriculture on the environment. A disaggregation at the municipality level with more than 9.000 administrative units, instead of currently used 316 counties, would tremendously improve the environmental impact analysis. Two sets of data are used for this purpose. The first are geo-referenced data, that are, however, incomplete with respect its coverage of production activities in agriculture. The second set is the micro census statistic itself, that has a full coverage, but data protection rules (DPR) prohibit its straightforward use. The paper show how this bottleneck can be passed to obtain a reliable modelling data set at municipality... Tipo: Conference Paper or Presentation Palavras-chave: Highest Posterior Density estimator (HPD); RAUMIS; Down scaling; Agricultural and Food Policy; C11; C61; C81; Q15. Ano: 2011 URL: http://purl.umn.edu/99248 Precaution and Protectionism: GM Food and the WTO AgEcon Rigby, Dan; Burton, Michael P.; Young, Trevor. The dispute between the US and EU over GM foods at the WTO is examined in terms of the issues it raises about protectionism and environmental protection and precaution. The issue of whether GM, GM Derived and Non-GM foods are equivalent to each other is examined using data from a national choice modelling study in the UK. These categories of food are critical since they underpin the EU's new food labelling regime which it hoped would defuse the WTO dispute. The results are analysed using a Bayesian mixed logit model which allows greater flexibility in the modelling of preference distributions. This is particularly crucial where, as in this case, bi-modal distributions are identified with some indifferent or mildly averse to GM foodtypes while others are... Tipo: Conference Paper or Presentation Palavras-chave: GM food; Mixed logit; WTP; Bayesian; WTO; International Relations/Trade; C11; C24; C25; D12; Q18. Ano: 2005 URL: http://purl.umn.edu/24447 Salvage the treasure of geographic information in Farm census data AgEcon Gocht, Alexander; Roder, Norbert. In Germany, since several decades the RAUMIS modelling system is applied for policy impact assessments to measure the impact of agriculture on the environment. A disaggregation at the municipality level with more than 9.600 administrative units, instead of currently used 316 counties, would tremendously improve the environmental impact analysis. Two sets of data are used for this purpose. The first are geo-referenced data, that are, however, incomplete with respect its coverage of production activities in agriculture. The second set is the micro census statistic itself, that has a full coverage, but data protection rules (DPR) prohibit its straightforward use. The paper show how this bottleneck can be passed to obtain a reliable modelling data set at... Tipo: Conference Paper or Presentation Palavras-chave: Highest Posterior Density estimator (HPD); RAUMIS; Down scaling; Research Methods/ Statistical Methods; C11; C61; C81; Q15. Ano: 2011 URL: http://purl.umn.edu/115982 Salvage the treasure of geographic information in Farm census data AgEcon Gocht, Alexander; Roder, Norbert. In Germany, since several decades the RAUMIS modelling system is applied for policy impact assessments to measure the impact of agriculture on the environment. A disaggregation at the municipality level with more than 9.600 administrative units, instead of currently used 316 counties, would tremendously improve the environmental impact analysis. Two sets of data are used for this purpose. The first are geo-referenced data, that are, however, incomplete with respect its coverage of production activities in agriculture. The second set is the micro census statistic itself, that has a full coverage, but data protection rules (DPR) prohibit its straightforward use. The paper show how this bottleneck can be passed to obtain a reliable modelling data set at... Tipo: Conference Paper or Presentation Palavras-chave: Highest Posterior Density estimator (HPD); RAUMIS; Down scaling; Research Methods/ Statistical Methods; C11; C61; C81; Q15. Ano: 2011 URL: http://purl.umn.edu/114824 Spatial Disaggregation of Agricultural Production Data AgEcon Howitt, Richard E.; Reynaud, Arnaud. In this paper we develop a dynamic data-consistent way for estimating agricultural land use choices at a disaggregate level (district-level), using more aggregate data (regional-level). The disaggregation procedure requires two steps. The first step consists in specifying and estimating a dynamic model of land use at the regional level. In the second step, we disaggregate outcomes of the aggregate model using maximum entropy (ME). The ME disaggregation procedure is applied to a sample of California data. The sample includes 6 districts located in Central Valley and 8 possible crops, namely: Alfalfa, Cotton, Field, Grain, Melons, Tomatoes, Vegetables and Subtropical. The disaggregation procedure enables the recovery of land use at the district-level with an... Tipo: Conference Paper or Presentation Palavras-chave: Disaggregation; Bayesian method; Maximum entropy; Land use; Production Economics; C11; C44; Q12. Ano: 2002 URL: http://purl.umn.edu/24961 Testing for Convergence Clubs in Income Per-Capita: A Predictive Density Approach AgEcon Canova, Fabio. The paper proposes a technique to jointly tests for groupings of unknown size in the cross sectional dimension of a panel and estimates the parameters of each group, and applies it to identifying convergence clubs in income per-capita. The approach uses the predictive density of the data, conditional on the parameters of the model. The steady state distribution of European regional data clusters around four poles of attraction with different economic features. The distribution of income per-capita of OECD countries has two poles of attraction and each group has clearly identifiable economics characteristics. In diesem Beitrag wird eine Methode vorgestellt, mit der es möglich ist, Gruppierungen von Querschnittsdaten von zunächst unbekanntem Umfang... Tipo: Working or Discussion Paper Palavras-chave: Heterogeneities; Panel Data; Predictive Density; Income Inequality; International Development; C11; D90; 047. Ano: 2001 URL: http://purl.umn.edu/26361 The Origin, Development And Structure Of Demand For Plant Genetic Resources. The Impact Of The In Trust Agreements To The CGIAR Collections Availability AgEcon Caracciolo, Francesco; Gotor, Elisabetta; Holloway, Garth J.; Watts, Jamie. The objective of this paper is to explore how the demand of germplasm held by CGIAR genebanks changed over time in order to assess the possible influence of the 1994 In Trust Agreements on germplasm demand. The proposed theoretic model motivates the realistic hypothesis that the consequences of the In-Trust Agreements lead to an enhancement of CGIAR germplasm utilization. Therefore the paper firstly examines the classical literature on biodiversity’s valuation and its recent developments and subsequently it investigates the origin of the agricultural biodiversity’s economic value, providing a basic conceptual framework to infer on factors determining the demand for germplasm. Two Bayesian estimation frameworks are applied to the IRRI accessions... Tipo: Conference Paper or Presentation Palavras-chave: Crop genetic resources; Germplasm collection; Search theoretic framework; Count data; Changepoints; O19; Q18; Q57; C11. Ano: 2008 URL: http://purl.umn.edu/36773 Registros recuperados: 18 Primeira ... 1 ... Última

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