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2011 Updated Arkansas Global Rice Model AgEcon
Wailes, Eric J.; Chavez, Eddie C..
The Arkansas Global Rice Model is based on a multi-country statistical simulation and econometric framework. The model is disaggregated by five world regions: Africa, the Americas, Asia, Europe, and Oceania. Each region includes country models which have a supply sector, a demand sector, a trade, stocks and price linkage equations. All equations used in this model are estimated using econometric procedures or identities. Estimates are based upon a set of explanatory variables including exogenous macroeconomic factors such as income, population, inflation rate, technology development, and especially, government determined policy variables which reflect the various mechanisms by which countries intervene in their rice sector economy. Individual country...
Tipo: Report Palavras-chave: Rice; Trade model; Policy; Agricultural and Food Policy; Research and Development/Tech Change/Emerging Technologies; CO2; C61; F11; F14; Q17; Q18.
Ano: 2011 URL: http://purl.umn.edu/102650
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A Comparison of Parametric Approximation Techniques to Continuous-Time Stochastic Dynamic Programming Problems AgEcon
Kompas, Tom; Chu, Long.
We compare three parametric techniques to approximate Hamilton-Jacobi-Bellman equations via unidimensional and multidimensional problems. The linear programming technique is very efficient for unidimensional problems and offers a balance of speed and accuracy for multidimensional problems. A comparable projection technique is shown to be slow, but has stable accuracy, whereas a perturbation technique has the least accuracy although its speed suffers least from the curse of dimensionality. The linear programming technique is also shown to be suitable for problems in resource management, including applications to biosecurity and marine reserve design.
Tipo: Journal Article Palavras-chave: Stochastic dynamic programming; Parametric approximation; Perturbation; Projection; Linear programming; Optimal fishing; Marine reserves; Research Methods/ Statistical Methods; Resource /Energy Economics and Policy; C61; C63; Q22.
Ano: 2010 URL: http://purl.umn.edu/95044
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A Dynamic Decision Model of Technology Adoption under Uncertainty: Case of Herbicide-Resistant Rice AgEcon
Annou, Mamane Malam; Wailes, Eric J.; Thomsen, Michael R..
Herbicide-resistant (HR) rice technology is a potential tool for control of red rice in commercial rice production. Using an ex ante mathematical programming framework, this research presents an empirical analysis of HR rice technology adoption under uncertainty. The analysis accounts for stochastic germination of red rice and sheath blight to model a profit maximization problem of crop rotation among HR rice, regular rice, and soybeans. The results demonstrate that risk attitudes and technology efficiency determine adoption rates and optimal rotation patterns.
Tipo: Journal Article Palavras-chave: Biotechnology; Herbicide resistance; Mathematical programming; Profit maximization; Rice; Risk; Rotation; Technology; Adoption; Crop Production/Industries; Production Economics; Research and Development/Tech Change/Emerging Technologies; Q16; Q18; O33; C61.
Ano: 2005 URL: http://purl.umn.edu/43724
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A FARM LEVEL ANALYSIS OF THE RELATION BETWEEN CAP REFORMS AND LOCAL ENVIRONMENTAL LEGISLATIONS: HOW AND IN WHICH EXTENT FLEMISH DAIRY FARMERS CAN FILL UP EXTRA MILK QUOTA? AgEcon
Van der Straeten, Bart; Buysse, Jeroen; Nolte, Stephan; Marchand, Fleur L.; Lauwers, Ludwig H.; Claeys, Dakerlia; Van Huylenbroeck, Guido.
The agricultural policies shift gradually from EU-level organised market interventions to local organised environmental policies. This paper explores the growth possibilities of the Flemish dairy sector with the outlook of a quota abolishment as a case study of this policy shift. The dairy quota policy seems very restrictive for the highly profitable Flemish dairy sector, but the environmental restrictions from the manure regulation can limit the growth of the dairy sector as well. The paper uses a spatial multi-agent simulation model applied to a sample of 40.000 farms to estimate price development of emission rights and their possible impact on the growth of the dairy production. The results show that a higher milk production leads to higher prices for...
Tipo: Conference Paper or Presentation Palavras-chave: Milk quota; Manure emission rights; Mathematical programming; Flanders; Agricultural and Food Policy; Industrial Organization; Research Methods/ Statistical Methods; C02; C61; L11; Q18.
Ano: 2008 URL: http://purl.umn.edu/44846
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A Microeconomic Model for Subsidies Allocation: the Case of Belarus AgEcon
Svetlov, Nikolai M.; Kazakevich, Iryna A..
The paper develops a microeconomic methodological framework that allows approaching subsidy allocation across the types of assets and impact of subsidies on agricultural outputs and profits. The methodology is based on a non-parametric production frontier estimation. The empirical application is made to 1084 Belarusian corporate farms. The results suggest targeting governmental support at grain and milk production. In this case, 4.14 trillion Belarusian roubles of subsidies increase the overall profit of the sample farms by 1.46 trillion. In the case of targeting, the farms with higher overall efficiency are more sensitive to the support and are able to absorb larger amount of subsidies. The opposite is true in the absence of targeting.
Tipo: Conference Paper or Presentation Palavras-chave: Microeconomic model; Data envelopment; Subsidies; Belarus; Agricultural and Food Policy; Institutional and Behavioral Economics; Political Economy; K18; C61.
Ano: 2010 URL: http://purl.umn.edu/90826
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A Model of Producer Incentives for Livestock Disease Management AgEcon
Ranjan, Ram; Lubowski, Ruben N..
We examine the management of livestock diseases from the producers' perspective, incorporating information and incentive asymmetries between producers and regulators. Using a dynamic model, we examine responses to different policy options including indemnity payments, subsidies to report at-risk animals, monitoring, and regulatory approaches to decreasing infection risks when perverse incentives and multiple policies interact. This conceptual analysis illustrates the importance of designing efficient combinations of regulatory and incentive-based policies.
Tipo: Working or Discussion Paper Palavras-chave: Livestock disease; Asymmetric information; Reporting; Indemnities; Risk management; Livestock Production/Industries; C61; D82; Q12; Q18; Q28.
Ano: 2004 URL: http://purl.umn.edu/15653
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A Multi-Period Analysis of Two Common Livestock Management Strategies Given Fluctuating Precipitation and Variable Prices AgEcon
Ritten, John P.; Frasier, W. Marshall; Bastian, Christopher T.; Paisley, Steven I.; Smith, Michael A.; Mooney, Sian.
Many areas of the US recently endured a severe drought and management strategies to cope with the lack of forage production varied. A multi-period mathematical model is presented that estimates the outcomes of two common producer responses to changes in precipitation, partial liquidation and purchasing hay, given fluctuating cattle prices over a long term planning horizon. Results were further summarized with regression analysis and selected elasticities were calculated to reflect the sensitivity of outcomes to variability in precipitation and livestock prices. Although little impact was seen from utilizing additional hay as a strategy during drought, producers who follow this strategy are in a position to market more animals immediately post drought in...
Tipo: Journal Article Palavras-chave: Drought management; Mathematical programming; Herd liquidation; Price cycle; Cattle management; Agribusiness; Agricultural Finance; Farm Management; Livestock Production/Industries; Production Economics; Productivity Analysis; Research Methods/ Statistical Methods; Q12; C61; D24.
Ano: 2010 URL: http://purl.umn.edu/90673
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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 Participatory Approach to Assess the Effectiveness of Responses to Cope with Flood Risk AgEcon
Ceccato, Lucia; Giannini, Valentina; Giupponi, Carlo.
This work illustrates the preliminary findings of a participatory research process aimed at identifying responses for sustainable water management in a climate change perspective, in two river basins in Europe and Asia. The paper describes the methodology implemented through local workshops, aimed at eliciting and evaluating possible responses to flood risk. Participatory workshops allowed for the identification of four categories of possible responses and a set of nine evaluation criteria, three for each of the three pillars of sustainable development. The main outcome of such activities consists in the ranking of broad response categories instrumental to the objective of the Brahmatwinn research project, i.e. the identification of Integrated Water...
Tipo: Working or Discussion Paper Palavras-chave: Participatory Process; Climate Change; Flood Risk; Decision Support System; Multi Criteria Analysis; MCA; Eliciting Responses; Evaluating Responses; Integrated Water Resources Management; IWRM; Mulino Decision Support System; MDSS; Environmental Economics and Policy; C61; Q01; Q54; Q56; Q58.
Ano: 2010 URL: http://purl.umn.edu/60662
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A Principal-Agent Model for Investigating Traceability Systems Incentives on Food Safety AgEcon
Resende Filho, Moises de Andrade.
This article investigates the effects of contingent payments and a traceability system's expected traceback rate of success on the food safety effort exerted by raw material suppliers. This sheds light on when contingent payments and the reliability of a traceability system are substitutes and complements to each other in terms of inducing raw material suppliers to exert higher food safety effort. In addition, the effect of higher penalties and costs of food safety crisis on the effort to be induced by buyers (principal) on suppliers (agents) is investigated under a symmetric information setting. Finally, the asymmetric information setting is formalized as a principal-agent model and left to be explored in a future work. Some numerical exercises are...
Tipo: Conference Paper or Presentation Palavras-chave: Information Asymmetry; Identity Preservation; Food Traceability; Supply Chain Management.; Food Consumption/Nutrition/Food Safety; D82; D86; C61.
Ano: 2007 URL: http://purl.umn.edu/7897
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A Search Model for Joint Implementation AgEcon
Bella, Giovanni.
The aim of this paper is to present a search model in the field of environmental economics, where so-called clean and dirty producers enter the trading market, both looking for a partner with whom to exchange the goods they are endowed with. The model derived in this paper is rather simple. Nevertheless, it is able to produce a series of interesting results and useful insights, and is conveniently used here as a framework to explain the functioning of Joint Implementation programmes for polluting emissions’ reduction.
Tipo: Working or Discussion Paper Palavras-chave: Environmental economics; Search theory; Market failures; Environmental Economics and Policy; C61; O13; Q26.
Ano: 2009 URL: http://purl.umn.edu/54356
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A spatial bio-economic modelling approach on the trade-offs between global bioenergy demand, agricultural intensification, expansion, and trade AgEcon
Lotze-Campen, Hermann; Popp, Alexander; Beringer, Tim; Muller, Christoph; Lucht, Wolfgang.
Increased future demands for food, fibre and fuels from biomass can only be met if the available land and water resources on a global scale are used and managed as efficiently as possible. The main routes for making the global agricultural system more productive are through intensification and technological change on currently used agricultural land, land expansion into currently non-agricultural areas, and international trade in agricultural commodities and processed goods. In order to analyse the trade-offs and synergies between these options, we present a global bio-economic modelling approach with a special focus on spatially explicit land and water constraints as well as technological change in agricultural production. For a given bioenergy demand...
Tipo: Conference Paper or Presentation Palavras-chave: Land use change; Spatial modelling; Technological change; Environmental Economics and Policy; International Development; International Relations/Trade; Land Economics/Use; Research and Development/Tech Change/Emerging Technologies; C61; F15; Q24; Q25.
Ano: 2009 URL: http://purl.umn.edu/51458
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A Stochastic Multiple Players Multi-Issues Bargaining Model for the Piave River Basin AgEcon
Sgobbi, Alessandra; Carraro, Carlo.
The objective of this paper is to investigate the usefulness of non-cooperative bargaining theory for the analysis of negotiations on water allocation and management. We explore the impacts of different economic incentives, a stochastic environment and varying individual preferences on players’ strategies and equilibrium outcomes through numerical simulations of a multilateral, multiple issues, non-cooperative bargaining model of water allocation in the Piave River Basin, in the North East of Italy. Players negotiate in an alternating-offer manner over the sharing of water resources (quantity and quality). Exogenous uncertainty over the size of the negotiated amount of water is introduced to capture the fact that water availability is not known with...
Tipo: Working or Discussion Paper Palavras-chave: Bargaining; Non-Cooperative Game Theory; Simulation Models; Uncertainty; Environmental Economics and Policy; C61; C71; C78.
Ano: 2007 URL: http://purl.umn.edu/7446
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A Whole Farm Analysis of the Influence of Auto-Steer Navigation on Net Returns, Risk, and Production Practices AgEcon
Shockley, Jordan M.; Dillon, Carl R.; Stombaugh, Timothy S..
A whole farm economic analysis was conducted to provide a detailed assessment into the economic, risk, and production implications due to the adoption of auto-steer navigation. It was determined that auto-steer navigation was profitable for a grain farmer in Kentucky with net returns increasing up to 0.90% ($3.35/acre). Additionally, the technology could be used in reducing production risk. Adoption of the technology also alters production practices for optimal use.
Tipo: Journal Article Palavras-chave: Economics; Farm management; Mean-variance; Precision agriculture; Simulation; Farm Management; Risk and Uncertainty; C61; C63; D81; Q12; Q16.
Ano: 2011 URL: http://purl.umn.edu/100640
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ACT Now or Later: The Economics of Malaria Resistance AgEcon
Laxminarayan, Ramanan.
In the past, malaria control efforts in sub-Saharan Africa have relied on a combination of vector control and effective treatment using chloroquine. With increasing resistance to chloroquine, attention has now turned to alternative treatment strategies to replace this failing drug. Although there are strong theoretical arguments in favor of switching to more expensive artemisinin-based combination treatments (ACTs), the validity of these arguments in the face of financial constraints has not been previously analyzed. In this paper, we use a Bioeconomic model of malaria transmission and evolution of drug resistance to examine questions of optimal treatment strategy and coverage when drug resistance places an additional constraint on choices available to the...
Tipo: Working or Discussion Paper Palavras-chave: Malaria; Mathematical models; Drug resistance; Bioeconomics; Health Economics and Policy; I10; I19; C61.
Ano: 2003 URL: http://purl.umn.edu/10699
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Aggregation and Calibration of Agricultural Sector Models Through Crop Mix Restrictions and Marginal Profit Adjustments AgEcon
Wiborg, Torben; McCarl, Bruce A.; Rasmussen, Svend; Schneider, Uwe A..
All agricultural sector models must deal with aggregation and calibration somehow. The aggregation problem involves treating a group of producers as if they all responded in the same way as a single representative unit. The calibration problem concerns making a model reproduce as closely as possible an empirically observed set of decision maker actions. This paper shows how both calibration and aggregation are addressed through crop mix restrictions combined with marginal profit adjust-ments.
Tipo: Conference Paper or Presentation Palavras-chave: Mathematical programming; Aggregation; Calibration; Crop mix; Marginal cost; Agricultural sector model; Agribusiness; C6; C61; Q1; Q11; Q17; Q18; R12; R13; R14.
Ano: 2005 URL: http://purl.umn.edu/24567
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AGRICULTURAL PRICE VOLATILITY UNDER CLIMATE CHANGE: The Impact of Multiple Objectives on Commodity Prices AgEcon
Fuss, Sabine; Havlik, Petr; Szolgayova, Jana; Obersteiner, Michael; Schmid, Erwin.
Agricultural price volatility has moved to the forefront of research efforts and political discussion, where much work is already being undertaken with respect to the impact of fluctuations in input prices (e.g. fertilizer, feed and energy). In this paper we also want to take into account the impact of climate change on prices via increased volatility in crop yields. In addition, we analyze the impact of having multiple objectives competing for the land on which crops are grown. In particular, we want to address the concerns that have been voiced about biofuel targets and calls for prioritization of food security.
Tipo: Presentation Palavras-chave: Energy; Food security; Food price volatility; Optimization under uncertainty; Risk and Uncertainty; Q12; Q18; Q28; C61; D81.
Ano: 2012 URL: http://purl.umn.edu/122539
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Agriculture, Income Risks and Rural Poverty Dynamics: Strategies of Smallholder Producers in Kenya AgEcon
Kuyiah, Joanne Wasswa; Obare, Gideon A.; Herrero, Mario; Waithaka, Michael M..
Poverty in Kenya has been on the increase over the last decade. It is estimated that 56% of the total population live in absolute poverty. Most of the poor reside in rural areas where agriculture is the main livelihood activity. Majority of Kenya's farmers are smallholders. They account for 75% of the total agricultural output and about 70% of marketed agricultural produce. The fate of smallholder agriculture in this country is therefore central to poverty reduction. A collapse in output and incomes from smallholder agriculture is likely to have damaging welfare effects and retard pro-poor economic growth. Smallholders often operate in a risky environment, which affects the level and variability of household resource endowments and income. The importance...
Tipo: Conference Paper or Presentation Palavras-chave: Smallholder farms; Income risk; Rural Poverty; Linear Programming; Kenya; Farm Management; C61; D13; L23; Q18.
Ano: 2006 URL: http://purl.umn.edu/25596
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Ambiguous Aggregation of Expert Opinions: The Case of Optimal R&D Investment AgEcon
Athanassoglou, Stergios; Bosetti, Valentina; Maere d'Aertrycke, Gauthier de.
How should a decision-maker allocate R&D funds when a group of experts provides divergent estimates on a technology's potential effectiveness? To address this question, we propose a simple decision-theoretic framework that takes into account ambiguity over the aggregation of expert opinion and a decision-maker's attitude towards it. In line with the paper's focus on R&D investment, decision variables in our model may affect experts' subjective probability distributions of the future potential of a technology. Using results from convex optimization, we are able to establish a number of analytical results including a closed-form expression of our model's value function, as well as a thorough investigation of its differentiability properties. We apply...
Tipo: Working Paper Palavras-chave: Ambiguity; Expert Opinions; R&D; Convex/Conic Optimization; Aggregation; Research and Development/Tech Change/Emerging Technologies; C61; D81; Q42.
Ano: 2012 URL: http://purl.umn.edu/121719
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An Agro-Economic Production Model for a Middle European River Basin - First Results of CAP Reform Scenario Calculations AgEcon
Henseler, Martin; Krimly, Tatjana; Wirsig, Alexander.
ACRE is an Agro-eConomic model for agricultural pRoduction on rEgional level. Based on an extension of Positive Mathematical Programming (PMP) this model was developed as a decision tool for politics with respect to questions of global change- and political scenarios. Currently, ACRE is applied in the RIVERTWIN-Neckar project and politic scenarios of the CAP reform 2003 were calculated. This paper introduces ACRE, its theoretical framework, and the first results of political scenario calculations, which where done for the Neckar river basin.
Tipo: Conference Paper or Presentation Palavras-chave: Agricultural production model; Regional model; Interdisciplinary projects; CAP reform 2003; Positive Mathematical Programming; Agricultural and Food Policy; E23; Q15; Q21; Q18; C61.
Ano: 2006 URL: http://purl.umn.edu/25612
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