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Registros recuperados: 61
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A calibrated agricultural water demand model for three regions in northern Baja California Agrociencia
Medellín-Azuara,Josué; Howitt,Richard E.; Waller-Barrera,Cynthia; Mendoza-Espinosa,Leopoldo G.; Lund,Jay R.; Taylor,Joseph E..
Irrigated agriculture is the largest water user in many regions, and agricultural water use efficiency and consumption has been studied by several authors. This paper provides a framework and application of economic valuation of water for agriculture in three regions in northern Baja California, Mexico, namely Guadalupe, Maneadero and Mexicali Valleys. Positive mathematical programming (PMP), a deductive valuation technique, was the framework used for this estimation using water delivery data reported by the National Water Commission in Mexicali, production costs and cultivated area, production factors use from the Agriculture Ministry (SAGARPA); and other data from previous studies. Analysis of the results shows that marginal economic water value in...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Mathematical programming; Baja California; Economic water valuation.
Ano: 2009 URL: http://www.scielo.org.mx/scielo.php?script=sci_arttext&pid=S1405-31952009000200001
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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 Heuristic Optimization Model for Vegetable Production and Marketing Decisions AgEcon
Dillon, Carl R.; Vassalos, Michael.
Poster presentation at 2012 AAEA
Tipo: Presentation Palavras-chave: Mathematical programming; Decision making; Vegetables; Heuristics; Farm Management; Production Economics.
Ano: 2012 URL: http://purl.umn.edu/123854
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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 NOTE ON FIXING MISBEHAVING MATHEMATICAL PROGRAMS: POST-OPTIMALITY PROCEDURES AND GAMS-RELATED SOFTWARE AgEcon
McCarl, Bruce A..
Mathematical programming formulations can yield faulty answers. Models can be unbounded, infeasible, or optimal with unrealistic answers. This article presents techniques for theory-based discovery of the cause of faulty models. The approaches are demonstrated in the context of linear programming. They have been computerized and interfaced using the General Algebraic Modeling System (GAMS), and are distributed free of charge through new GAMS versions and an outline web page.
Tipo: Journal Article Palavras-chave: Debugging; GAMS software; Mathematical programming; Research Methods/ Statistical Methods.
Ano: 1998 URL: http://purl.umn.edu/15553
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ACHIEVING EFFICIENCY AND EQUITY IN IRRIGATION MANAGEMENT: AN OPTIMIZATION MODEL OF THE EL ANGEL WATERSHED, CARCHI, ECUADOR AgEcon
Evans, Elizabeth M.; Lee, David R.; Boisvert, Richard N..
The objective of this paper is to address the problems of inefficiency and inequity in water allocation in the El Angel watershed, located in Ecuador's Sierra region. Water is captured in a high-altitude region of the watershed and distributed downstream to producers in four elevation-defined zones via a system of canals. Upstream and downstream producers face radically different conditions with respect to climate and terrain. A mathematical programming model was created to study the consequences of addressing chronic water scarcity problems in the watershed by shifting water resources between the four zones. The model captures the nature of water use by humans, crops and dual purpose cattle. Its objective function maximizes producer welfare as...
Tipo: Conference Paper or Presentation Palavras-chave: Mathematical programming; Water allocation; Efficiency; Equity; Resource /Energy Economics and Policy.
Ano: 2002 URL: http://purl.umn.edu/19742
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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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Agri-Environmental Policies When the Spatial Pattern of Biodiversity Reserves Matters AgEcon
Bamiére, Laure; David, Maia; Vermont, Bruno.
The aim of this paper is to compare different policy instruments for cost-effective habitat conservation on agricultural lands, when the desired spatial pattern of reserves is a random mosaic. We use a spatially explicit mathematical programming model which studies the farmers' behavior as profit maximizers under technical and administrative constraints. Facing different policy measures, each farmer chooses its land-use at the field level, which determines the landscape at the regional level. A spatial pattern index (Ripley L function) is then associated to the obtained landscape, indicating on the degree of dispersion of the reserve. We compare a subsidy per hectare of reserve with an auction scheme and an agglomeration malus. We find that the auction is...
Tipo: Conference Paper or Presentation Palavras-chave: Agri-environmental policies; Biodiversity; Mathematical programming; Spatial optimization; Reserve design; Cost-efficiency; Environmental Economics and Policy; Resource /Energy Economics and Policy; H23; Q57; Q12; Q28.
Ano: 2011 URL: http://purl.umn.edu/114239
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Análisis de alternativas para la eliminación de la sobreexplotación de acuíferos en el Valle de Guadalentín AgEcon
Calatrava-Leyva, Javier; Guillem, Amanda; Martinez-Granados, David.
In this paper we analyse the economic impact of alternative water management instruments that allow addressing the problem of non-renewable groundwater pumping in the aquifers of the Guadalentín Valley (southeast Spain). Their impact is assessed using a partial equilibrium mathematical programming model that maximises the farm net margin resulting from the use of the available water resources for irrigation in the area. Our results show that the buyback of groundwater pumping rights is the option with the greatest public budgetary cost and economic impact. On the contrary, the combination of an environmental tax on groundwater pumping and the substitution of groundwater by subsidised desalinised water allow eliminating aquifer overdraft in the area while...
Tipo: Article Palavras-chave: Groundwater; Water economics; Water demand; Mathematical programming; Irrigation; Agricultural and Food Policy; Environmental Economics and Policy; Land Economics/Use; Resource /Energy Economics and Policy; Q25; C61.
Ano: 2011 URL: http://purl.umn.edu/120197
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Bio-energy production in the sugar industry: an integrated modeling approach AgEcon
Haque, Imdadul; Rozakis, Stelios; Ganko, Ewa; Kallivroussis, Leonidas.
Recent reforms in the Common Agricultural Policy and the sugar regime caused serious concerns for the future of the European sugar industry. At the same time, the European Commission considers transportation bio-fuels as a key factor for reducing reliance on imported fuels, emission levels of greenhouse gases and to meet rural development goals. Matching the sugar sector with bio-ethanol production may create opportunities for sustainable management of the existing sugar industry infrastructure and also serve bio-fuel policy targets. A partial equilibrium economic model is used in order to evaluate the shift from sugar to bio-ethanol production in Thessaly, Greece. In the agricultural feedstock supply and industrial processing sub-models are articulated...
Tipo: Conference Paper or Presentation Palavras-chave: Sugar beet; Grain; Ethanol; Mathematical programming; Greece; Agricultural and Food Policy; Food Consumption/Nutrition/Food Safety.
Ano: 2009 URL: http://purl.umn.edu/58026
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Biomass Supply from Alternative Cellulosic Crops and Crop Residues: A Preliminary Spatial Bioeconomic Modeling Approach AgEcon
Egbendewe-Mondzozo, Aklesso; Swinton, Scott M.; Izaurralde, R. Cesar; Manowitz, David H.; Zhang, Xuesong.
This paper introduces a spatial bioeconomic model for study of potential cellulosic biomass supply at regional scale. By modeling the profitability of alternative crop production practices, it captures the opportunity cost of replacing current crops by cellulosic biomass crops. The model draws upon biophysical crop input-output coefficients, price and cost data, and spatial transportation costs in the context of profit maximization theory. Yields are simulated using temperature, precipitation and soil quality data with various commercial crops and potential new cellulosic biomass crops. Three types of alternative crop management scenarios are simulated by varying crop rotation, fertilization and tillage. The cost of transporting biomass to a specific...
Tipo: Working or Discussion Paper Palavras-chave: Biomass production; Bioenergy supply; Biofuel policy; Bioenergy; Cellulosic ethanol; Agro-ecosystem economics; Ecosystem services economics; Agro-environmental trade-off analysis; Mathematical programming; EPIC; Agricultural and Food Policy; Crop Production/Industries; Environmental Economics and Policy; Land Economics/Use; Production Economics; Resource /Energy Economics and Policy; Q16; Q15; Q57; Q18.
Ano: 2010 URL: http://purl.umn.edu/98277
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Can Catfish Aquaculture be Profitable in Farm Ponds? AgEcon
Dasgupta, Siddhartha; Wurts, William; Durborow, Robert.
Extensive channel catfish farming is a means of utilizing farm ponds for aquaculture production for either supplementary income of home use. This involves stocking catfish at sufficiently low densities such that a pond is able to assimilate excess feed and fish wastes without needing supplemental aeration or chemicals to keep water quality from reaching toxic levels. This is "low-tech" aquaculture and requires little producer labor/management inputs. A mathematical model of extensive catfish culture in farm ponds was presented in this paper. This model used data from Kentucky where part-time producers, with a minimum of aquaculture experience and time for pond management, are involved in culturing catfish for retail/live markets. Results of this model...
Tipo: Conference Paper or Presentation Palavras-chave: Mathematical programming; Catfish; Aquaculture; Farm ponds; Livestock Production/Industries.
Ano: 2007 URL: http://purl.umn.edu/34893
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Comparative Performance of Selected Mathematical Programming Models AgEcon
Arriaza Balmón, Manuel; Gomez-Limon, Jose Antonio.
This study compares the predictive performance of several mathematical programming models. Using the cropping patterns, yields and crop gross margins of eighteen farms over a period of five years we compare the models' optimum solutions with observed crop distributions after the Reform of the EU Common Agricultural Policy of 1992. The results show that the best prediction corresponds to a model that includes expected profit and a qualitative measure of crop riskiness. The results suggest that, in order to obtain reliable predictions, the modelling of farmers' responses to policy changes must consider the risk associated with any given cropping pattern. Finally, we test the ability of the proposed model to reproduce the farmers' observed behaviour with...
Tipo: Conference Paper or Presentation Palavras-chave: Model performance; Mathematical programming; Modelling; Decision-making; Resource /Energy Economics and Policy.
Ano: 2002 URL: http://purl.umn.edu/24792
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Comparison of Decision Rules for Subsurface Drip Irrigation Practices Using a Nonlinear Mathematical Programming Model AgEcon
Salim, Juma K.; Dillon, Carl R.; Saghaian, Sayed H.; Kanakasabai, Murali.
A comparison of decision rules has been made for case studies of corn production using subsurface drip irrigation under three agricultural management practices (no irrigation, uniform irrigation, and variable rate irrigation). The uniform irrigation strategy appeared to perform the best than the other two management practices under different risk scenarios.
Tipo: Conference Paper or Presentation Palavras-chave: Corn production; Mathematical programming; Profitability; Risk management; Subsurface drip irrigation; Variable rate irrigation; Farm Management.
Ano: 2005 URL: http://purl.umn.edu/35517
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Cost-Effectiveness of Nutrient Management and Buffers: Comparisons of Two Spatial Scenarios AgEcon
Bonham, John G.; Bosch, Darrell J.; Pease, James W..
Farmers and taxpayers would benefit from more cost-effective agricultural nutrient pollution control measures. The objectives of our study are (1) to assess compliance costs and reductions in phosphorus loadings from implementation of nutrient management and riparian buffers; and (2) to estimate how the spatial scenario, which is the method of representing farms within the watershed, affects estimated compliance costs and reductions in phosphorus deliveries. Estimated compliance costs are quite sensitive to the spatial scenario. Buffers are more cost-effective than nutrient management under one of the two spatial scenarios, whereas nutrient management is more cost-effective under the other scenario. Shifts to more erosive crops reduce the effectiveness...
Tipo: Journal Article Palavras-chave: Compliance costs; Geographic information systems (GIS); Mathematical programming; Nutrient management; Phosphorus (P); Pollution abatement; Riparian buffers; Spatial analysis; Environmental Economics and Policy; Land Economics/Use; Q12; Q52.
Ano: 2006 URL: http://purl.umn.edu/43746
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Crop insurance market development in a transition economy: The case of Kazakhstan AgEcon
Heidelbach, Olaf; Bokusheva, Raushan.
We analyze the current state and future requirements of an agricultural income stabilization mechanism in a transition country – namely, the crop insurance system in Kazakhstan. Three objectives will be pursued: First, factors influencing the development of the crop insurance market will be identified. Second, insurance’s capabilities to efficiently stabilize income under transition circumstances will be evaluated. Finally, recommendations for developing crop insurance as an effective income stabilization tool will be provided. Results indicate that the prevailing institutional framework for establishing a sustainable crop insurance system is rather weak, and available insurance products are not preventing the problem of asymmetric information to a...
Tipo: Conference Paper or Presentation Palavras-chave: Risk-management; Crop insurance; Institutions; Mathematical programming; Kazakhstan; Agricultural Finance; Risk and Uncertainty; D81; D82; G22; Q14.
Ano: 2009 URL: http://purl.umn.edu/51614
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Determining the Price-Responsiveness of Demands for Irrigation Water Deliveries versus Consumptive Use AgEcon
Scheierling, Susanne M.; Young, Robert A.; Cardon, Grant E..
A water-crop simulation/mathematical programming model of irrigation water demand in northeastern Colorado is formulated to develop an original concept of derived demand for consumptive use of water. Conventional demand functions for water deliveries are also developed, and the effect of hypothetical price increases on both consumption and delivery are illustrated. Findings indicate that demand elasticity estimates are quite sensitive to model specification, and consumptive use demand tends to be significantly less price-responsive than delivery demand. Thus price incentives are likely to have only limited impacts on basin-wide water consumption and would not make much additional water available for emerging demands.
Tipo: Journal Article Palavras-chave: Crop simulation; Irrigation; Mathematical programming; Water conservation; Water-demand elasticities; Water policy; Demand and Price Analysis; Resource /Energy Economics and Policy.
Ano: 2004 URL: http://purl.umn.edu/31107
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Development of a Partial Equilibrium Model of the EU Agriculture using Positivistic Mathematical Programming AgEcon
Yates, C.M.; Rehman, Tahir.
In order to respond to the current pressures on agriculture in the EU, the industry will have to go through fundamental structural change. Economic modelling provides the framework for understanding such changes. Mathematical programming is probably the most robust of all the modelling approaches notwithstanding several criticisms of the technique. Economists have long understood that profit maximisation is not the only objective of farmers. Although there are techniques to incorporate other objectives there does not exist a statistically rigorous method for estimating an appropriate objective functions. This problem also occurs at national and international levels of aggregation. This paper presents a new approach to modelling national and international...
Tipo: Conference Paper or Presentation Palavras-chave: Mathematical programming; Positivistic mathematical programming; Partial equilibrium; International trade; Policy analysis; Agricultural and Food Policy.
Ano: 2002 URL: http://purl.umn.edu/24878
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Development, Testing and Application of ACRE: An Agro-Economic Production Model on Regional Level AgEcon
Henseler, Martin; Wirsig, Alexander; Krimly, Tatjana.
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 scenarios. The validity of the theoretical approach as well as the algorithms has been tested by calculations with empirical data. Currently, ACRE is applied in large interdisciplinary projects. This paper introduces the development of ACRE, from the theoretical framework to testing its validity and current application.
Tipo: Conference Paper or Presentation Palavras-chave: Mathematical programming; Variant-activity; Regional model; Agricultural production model; Interdisciplinary projects; Agribusiness; C61; Q15; E23; Q21.
Ano: 2005 URL: http://purl.umn.edu/24770
Registros recuperados: 61
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