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Registros recuperados: 76
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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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A Spatial Equilibrium Model of the Impact of Bio-Fuels Energy Policy on Grain Transportation Flows AgEcon
Ahmedov, Zafarbek; Power, Gabriel J.; Vedenov, Dmitry V.; Fuller, Stephen W.; McCarl, Bruce A.; Vadali, Sharada.
Traffic flows in the U.S. have been affected by the substantial increase and, as of January 2009, decrease in biofuel production and use. This paper considers a framework to study the effect on grain transportation flows of the 2005 Energy Act and subsequent legislation, which mandated higher production levels of biofuels, e.g. ethanol and biodiesels. Future research will incorporate changes due to the recent economic slowdown.
Tipo: Conference Paper or Presentation Palavras-chave: Ethanol; Biodiesel; Spatial equilibrium; Quadratic programming; Agricultural and Food Policy; Crop Production/Industries; Resource /Energy Economics and Policy.
Ano: 2009 URL: http://purl.umn.edu/49837
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Adaptation to Climate Change: Land Use and Livestock Management Change in the U.S. AgEcon
Mu, Jianhong H.; McCarl, Bruce A..
Replaced with revised version of paper 01/26/11
Tipo: Conference Paper or Presentation Palavras-chave: Climate Change; Stocking Rate; Land Use; Livestock Management; Environmental Economics and Policy; Land Economics/Use; Livestock Production/Industries.
Ano: 2011 URL: http://purl.umn.edu/98708
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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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AN ECONOMIC, HYDROLOGIC, AND ENVIRONMENTAL ASSESSMENT OF WATER MANAGEMENT ALTERNATIVE PLANS FOR THE SOUTH CENTRAL TEXAS REGION AgEcon
Gillig, Dhazn; McCarl, Bruce A.; Boadu, Frederick O..
Regional water scarcity has motivated the South Central Texas Regional Water Planning Group to actively develop water management plans to address long-/short-term regional water needs. This study, therefore, develops an integrated Edwards Aquifer groundwater and river system simulation model to determine the "best" choice of regional water management plans using mixed-integer linear programming. The economic, hydrologic, and environmental consequences of the "best" choice of regional and other water management plans and options are evaluated and compared. Results indicate a tradeoff between the economic and environmental benefits. A slight decrease in economic benefit results in a substantial increase in environmental benefit.
Tipo: Journal Article Palavras-chave: Economic and hydrologic assessment; Edwards Aquifer; And water management plans; Resource /Energy Economics and Policy.
Ano: 2001 URL: http://purl.umn.edu/15296
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AN INVESTIGATION OF THE RELATIONSHIP BETWEEN CONSTRAINT OMISSION AND RISK AVERSION IN FIRM RISK PROGRAMMNG MODELS AgEcon
Musser, Wesley N.; McCarl, Bruce A.; Smith, G. Scott.
A model with omitted resource constraints is suggested as an alternative to a risk aversion model for explaining economic behavior. This paper uses two standard mathematical programming models to further explore this issue. One model is a standard profit maximization linear programming model and the other is a risk averse quadratic programming model with part of the constraints deleted. Theoretical investigation of these models demonstrates that risk aversion can substitute for omitted resource constraints. A small empirical model is then solved under both formulations. With resource constraints deleted, positive risk aversion is necessary to obtain a similar enterprise organization as under profit maximization with complete constraints. These two...
Tipo: Journal Article Palavras-chave: Risk and Uncertainty.
Ano: 1986 URL: http://purl.umn.edu/29787
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Animal Disease Pre-Event Preparedness versus Post-Event Response: When is it Economic to Protect? AgEcon
Elbakidze, Levan; McCarl, Bruce A..
We examine the economic tradeoff between the costs of pre-event preparedness and post-event response to the potential introduction of an infectious animal disease. In a simplified case study setting, we examine the conditions for optimality of an enhanced pre-event detection system considering various characteristics of a potential infectious cattle disease outbreak, costs of postevent response actions. We show that the decision to invest in pre-event preparedness activities depends on such factors as probability of disease introduction, disease spread rate, relative costs, ancillary benefits, and effectiveness of mitigation strategies.
Tipo: Journal Article Palavras-chave: Animal disease; Economic balance; Mitigation strategies; Preparedness; Response; Food Consumption/Nutrition/Food Safety; Food Security and Poverty; Livestock Production/Industries; Q1; Q18; D81.
Ano: 2006 URL: http://purl.umn.edu/43768
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Animal Disease Related Pre-event Investment and Post-event Compensation: A Multi-agent Problem AgEcon
Jin, Yanhong H.; McCarl, Bruce A..
We employ a game-theoretic principal agent framework to analyze the individual farmer and governmental behavior pre- and post-animal disease outbreak. We examine the gap between the privately optimal and socially optimal levels of ex ante biosecurity investment and then investigate how a well-designed differentiated compensation scheme can close this gap. Our results also show that the privately optimal investment is generally lower than the first best socially optimal level, and a well-designed differentiated compensation scheme conditional on ex ante biosecurity investment can induce private preventive investment at least greater than the second best socially optimal level when the government face constraints, or even increase approaching the first best...
Tipo: Conference Paper or Presentation Palavras-chave: Risk and Uncertainty.
Ano: 2006 URL: http://purl.umn.edu/21216
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Avian Influenza outbreaks and poultry production mitigation strategies in the U.S. AgEcon
Mu, Jianhong H.; McCarl, Bruce A..
In this paper, two AI mitigation strategies are examined, quarantine and vaccination. Meanwhile, associated welfare changes are evaluated by using FASOM. Results found that changes of total national welfare of U.S are insignificant with or without vaccination. Once comes to livestock producers, impacts become significant although magnitudes are small. For example, under 20% demand shocks, vaccination strategy dominates no vaccination at the production, market and national level. However, vaccination has no advantage when there is no demand shifts.
Tipo: Conference Paper or Presentation Palavras-chave: AI outbreak; Mitigation strategies; Vaccination; Demand shift; FASOM; Welfare; Agricultural and Food Policy; Consumer/Household Economics; Demand and Price Analysis; Food Consumption/Nutrition/Food Safety; Food Security and Poverty; Health Economics and Policy; Q1.
Ano: 2010 URL: http://purl.umn.edu/116452
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Bioenergy in a Greenhouse Mitigating World AgEcon
McCarl, Bruce A..
Tipo: Journal Article Palavras-chave: Environmental Economics and Policy; Resource /Energy Economics and Policy; Q1; Q4; Q54.
Ano: 2008 URL: http://purl.umn.edu/94503
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BIOFUELS, CLIMATE POLICY, AND WATER MANAGEMENT: ASSESSING POLICY-INDUCED SHIFTS ON AGRICULTURE’S EXTENSIVE AND INTENSIVE MARGINS AgEcon
Baker, Justin Scott; Murray, Brian C.; McCarl, Bruce A..
Biofuel expansion efforts and climate mitigation policy could fundamentally alter land management trends in U.S. agriculture and forestry (AF) by mandating biofuel feedstock production and providing incentives for greenhouse gas (GHG) emissions reduction and carbon sequestration from terrestrial sources. Research has shown that biofuel expansion can alter commodity markets, induce agricultural land expansion, and intensify production. Meanwhile, GHG mitigation efforts could limit agricultural expansion, reduce current cultivation, and lower management intensity by incentivizing GHG emissions reduction and carbon sequestration within AF. To date, little work has attempted to quantify biofuel and climate policy-induced shifts together along the extensive and...
Tipo: Conference Paper or Presentation Palavras-chave: Greenhouse gas mitigation; Biofuels; Water resource management; Environmental Economics and Policy; Production Economics; Resource /Energy Economics and Policy.
Ano: 2011 URL: http://purl.umn.edu/104912
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BIOPHYSICAL SIMULATION IN SUPPORT OF CROP PRODUCTION DECISIONS: A CASE STUDY IN THE BLACKLANDS REGION OF TEXAS AgEcon
Dillon, Carl R.; Mjelde, James W.; McCarl, Bruce A..
Economic feasibility of Texas Blacklands corn production in relation to sorghum, wheat, and cotton is studied. Biophysical simulation generated yield data are integrated with an economic decision model using quadratic programming. Given the various scenarios analyzed, corn is economically feasible for the Blacklands. A crop mix of half corn and half cotton production is selected under risk neutrality with wheat entering if risk aversion is present. Corn and grain sorghum production are highly substitutable. Profit effects attributed to changing corn planting dates are more pronounced than profit changes resulting from altering corn population or maturity class.
Tipo: Journal Article Palavras-chave: Crop Production/Industries.
Ano: 1989 URL: http://purl.umn.edu/30189
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Climate Change and Texas Water Planning: an Economic Analysis of Inter-basin Water Transfers AgEcon
Cai, Yongxia; McCarl, Bruce A..
Panel models with random effects are used to estimate how climate influences in-stream surface water supply, municipal water demand, crop yields and irrigation water use. The results are added into TEXRIVERSIM, a state wide economic, hydrological, environmental and inter-basin water transfer (IBTs) investment model, through the objective function and hydrological constraints. A climate change related scenario analysis from the Global Circulation Models (GCMs)--Hadley, Canadian, BCCR and NCAR with SRES scenarios A1B, B1, and A2 indicates that inter-basin water transfers not only greatly relax water scarcity problems for major cities and industrial counties, but also create growth opportunity for Houston. However, while destination basins receive the...
Tipo: Conference Paper or Presentation Palavras-chave: Climate Change; Inter-basin Water Transfers; Water Scarcity; Environmental Stream Flows; Environmental Economics and Policy; Q25; Q54; Q58.
Ano: 2009 URL: http://purl.umn.edu/49933
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CLIMATE CHANGE IMPACTS ON US AGRICULTURE AgEcon
Beach, Robert H.; Thomson, Allison M.; McCarl, Bruce A..
There is general consensus in the scientific literature that human-induced climate change has taken place and will continue to do so over the next century. The Fourth Assessment Report (AR4) of the Intergovernmental Panel on Climate Change concludes with “very high confidence” that anthropogenic activities such as fossil fuel burning and deforestation have affected the global climate. The AR4 also indicates that global average temperatures are expected to increase by another 1.1°C to 5.4°C by 2100, depending on the increase in atmospheric concentrations of greenhouse gases that takes place during this time. Increasing atmospheric carbon dioxide levels, temperature increases, altered precipitation patterns and other factors influenced by climate have...
Tipo: Conference Paper or Presentation Palavras-chave: Climate change; Crop yields; EPIC; FASOM; Crop Production/Industries; Environmental Economics and Policy; International Relations/Trade; Land Economics/Use; Resource /Energy Economics and Policy; C61; Q18; Q54.
Ano: 2010 URL: http://purl.umn.edu/91393
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CLIMATE CHANGE INFLUENCES ON THE RISK OF AVIAN INFLUENZA OUTBREAKS AND ASSOCIATED ECONOMIC LOSS AgEcon
Mu, Jianhong H.; McCarl, Bruce A.; Wu, Ximing; Gan, Li.
This paper examines the effect that climate has on Avian Influenza outbreak probability. The statistical analysis shows across a broad region the probability of an outbreak declines by 0.22% when the temperature rises 1 Celsius degree and increases by 0.34% when precipitation increases by 1millimeter. These results indicate that the realized climate change of the last 20 years not only has been a factor behind recent HPAI outbreaks, but that climate change is likely to play an even greater role in the future. The statistical results indicate that overall, the risk of an AI outbreak has been increased by 51% under past climate change and 3-4% under future climate change. An economic evaluation shows the increased probability of outbreaks has caused...
Tipo: Conference Paper or Presentation Palavras-chave: Climate change; Avian Influenza outbreaks; GDP loss; Environmental Economics and Policy; Research Methods/ Statistical Methods.
Ano: 2011 URL: http://purl.umn.edu/103637
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Crop Yield Growth and Its Implication for the International Effects of US Bioenergy and Climate Policies (Draft) AgEcon
Feng, Siyi J.; McCarl, Bruce A.; Havlik, Petr.
Replaced with revised version of paper 07/22/11.
Tipo: Conference Paper or Presentation Palavras-chave: Environmental Economics and Policy; Land Economics/Use; Research and Development/Tech Change/Emerging Technologies; Resource /Energy Economics and Policy.
Ano: 2011 URL: http://purl.umn.edu/103518
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Does Negative Information Always Hurt Meat Demand? An Examination of Avian Influenza Information Impacts on U.S. AgEcon
Mu, Jianhong H.; McCarl, Bruce A..
Consumers’ consumption patterns could be affected by food safety information, however, it is more important to consider where the food safety issue occurs. If the food safety issue happens in other countries, in other words, it outbreaks out of the target market, negative information may be beneficial; in contrast, if the food safety issue occurs within the market, results may consistent with previous studies. Based on this assumption, this paper reinvestigates the impacts of AI media coverage and BSE cases on the demand of meat in U.S. market. Estimated results provide supports for our assumption, i.e., AI information has positive effect on poultry and turkey demands in short term, and BSE affect beef demand negatively.
Tipo: Conference Paper or Presentation Palavras-chave: Avian influenza media coverage; AI human case; BSE announcements; AIDS model; Meat demand; Agricultural and Food Policy; Consumer/Household Economics; Demand and Price Analysis; Food Consumption/Nutrition/Food Safety; Food Security and Poverty; Health Economics and Policy; Q1.
Ano: 2010 URL: http://purl.umn.edu/116450
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Economic and Groundwater Use Implications of Climate Change and Bioenergy Feedstock Production in the Ogallala Aquifer Region AgEcon
Wang, Weiwei; Park, Seong Cheol; McCarl, Bruce A.; Amosson, Stephen H..
The sustainable water use especially for irrigated agriculture in the Texas Panhandle Region is a major concern. A semi-arid climate and average low rainfalls results in little surface water being available year-round. The Ogallala Aquifer is the primary source of irrigation water in this region. The intensive irrigated agricultural production and growing livestock industry have led to substantial decline of water tables. Furthermore, climate change and growing bioenergy feedstock productions exacerbates the water shortage and quality problems. Given the critical dependence of the regional economy on Ogallala Aquifer, underground water use is an intergenerational issue that must be evaluated in terms of the sustainability of agricultural activities in the...
Tipo: Conference Paper or Presentation Palavras-chave: Groundwater; Land Use Change; Climate Change; Bioenergy feedstock; Dynamic Optimization Model; Deficit Irrigation; Environmental Economics and Policy; Land Economics/Use; Resource /Energy Economics and Policy; Q24; Q25; Q54.
Ano: 2011 URL: http://purl.umn.edu/103642
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ECONOMIC AND HYDROLOGIC IMPLICATIONS OF SUSPENDING IRRIGATION IN DRY YEARS AgEcon
Keplinger, Keith O.; McCarl, Bruce A.; Chowdhury, Manzoor E.; Lacewell, Ronald D..
A dry year irrigation suspension has been proposed as a way of reallocating water when aquifer levels are low for the Texas Edwards Aquifer. Under this program, farmers would be paid to suspend irrigation to allow more spring flow or nonagricultural pumping. When irrigation is suspended in the east, springflow response is markedly larger than when suspended in the western portions of the aquifer. Most acreage participates when a $90 per acre payment is offered before the cropping season. Considerably higher payments are needed and less water saved for a suspension program instituted during the cropping season.
Tipo: Journal Article Palavras-chave: Crop Production/Industries.
Ano: 1998 URL: http://purl.umn.edu/31172
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ECONOMIC IMPACTS OF CLIMATE CHANGE ON SOUTHERN FORESTS AgEcon
Burton, Diana M.; McCarl, Bruce A.; de Sousa, Claudio N.M.; Adams, Darius M.; Alig, Ralph J.; Winnett, Steven M..
A multiperiod regional mathematical programming model is used to evaluate the potential economic impacts of global climatic change on the southern U.S. forestry sector. Scenarios for forest biological response to climate change are developed for small and large changes in forest growth rates. Resulting changes in timber supply have economic impacts on producers and consumers in forest products markets, both nationally and regionally. Conclusions include outer dimensions of global climate change impacts and potential effects of smaller biological responses on the forestry sector both nationally and in the U.S. South. Relative impacts are found to be larger for producers than for consumers, and southern producers experience relatively greater changes in...
Tipo: Working or Discussion Paper Palavras-chave: Resource /Energy Economics and Policy.
Ano: 1997 URL: http://purl.umn.edu/24002
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