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We model dynamic consumer choice in a stochastic optimal control framework and show conditions under which observable market share data possess the Markov property. Using 30 years of annual aggregate milk consumption data differentiated by fat content, maximum entropy is used to estimate nonstationary transition probabilities showing how consumer tastes and preferences have changed over time. The maximum entropy approach allows for the estimation of a 4 × 4 transition probability matrix for each year of the sample. Results suggest that skim milk was an absorbing state over most of the sample but that the trend toward skim milk has decelerated and possibly reversed itself since 1998. Our approach provides a useful complement to existing parametric approaches to demand analysis when data are limited or the problem is ill‐posed. 相似文献
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Ching-Cheng Chang 《Agricultural Economics》2002,27(1):51-64
This paper intends to estimate the potential impact of climate change on Taiwan's agricultural sector. Yield response regression models are used to investigate the climate change's impact on 60 crops. A price‐endogenous mathematical programming model is then used to simulate the welfare impacts of yield changes under various climate change scenarios. Results suggest that both warming and climate variations have a significant but non‐monotonic impact on crop yields. Society as a whole would not suffer from warming, but a precipitation increase may be devastating to farmers. 相似文献
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European water policy, as set out in the Water Framework Directive (WFD), requires all EU Member States to implement volumetric water pricing at rates that roughly cover the total costs of providing water services. The objective of this paper is to develop a methodology that, for the different types of farm in an irrigable area, will enable us to analyse the differential impact that a pricing policy for irrigation water would have. For this purpose, Multi-Attribute Utility Theory (MAUT) mathematical programming models were used. The methodology is implemented on a representative area in the Duero Valley in Spain. Our results show the usefulness of differential analysis in evaluating the impact of a water pricing policy. This allows significant differences in the evolution of agricultural incomes to be observed, as well as the recovery of costs by the State, demand for agricultural employment and the consumption of agrochemicals resulting from rising prices of irrigation water in various groups of farmers within a given irrigated area. 相似文献
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Sone Ekman 《Agricultural Economics》2005,32(3):297-309
This article focuses on how the linkages between various farm‐level decisions affect the choice of measures to reduce nitrogen leaching from crop production. A mathematical programming model is developed. The model considers not only management decisions that affect nitrogen leaching directly, but also other decision variables such as scheduling of field operations and machinery investments. A simplified analysis that ignores the latter management decisions, and the linkages between the various decisions, may result in abatement policies that are not cost‐effective because the policies will have other effects than expected. As an example, the empirical results show that subsidies to catch crops and spring ploughing may contribute to increased nitrogen load, quite contrary to the purpose of these subsidies. Further, it is noted that the characteristics of the production system make it costly to change land use, tillage practices, or fertilizer use drastically. Instead, cost‐effective nitrogen abatement includes a mix of various adjustments of farm‐level production practices. The EU set‐aside payment appears to reduce abatement costs. 相似文献
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There is interest in society in general and in the agricultural and forestry sectors concerning a land‐based role in greenhouse gas mitigation reduction. Numerous studies have estimated the potential supply schedules at which agriculture and forestry could produce greenhouse gas offsets. However, such studies vary widely in critical assumptions regarding economic market adjustments, allowed scope of mitigation alternatives, and region of focus. Here, we examine the effects of using different assumptions on the total emission mitigation supply curve from agriculture and forestry in the United States. To do this we employ the U.S.‐based Agricultural Sector and Mitigation of Greenhouse Gas Model and find that variations in such factors can have profound effects on the results. Differences between commonly employed methods shift economic mitigation potentials from –55 to + 85%. The bias is stronger at higher carbon prices due to afforestation and energy crop plantations that reduce supply of traditional commodities. Lower carbon prices promote management changes with smaller impacts on commodity supply. 相似文献
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In this study, we develop a conceptual bioeconomic model of floriculture production with aesthetic benefits, wherein optimal decision rules depend on an intertemporal economic objective to maximize profits subject to economic and biological processes. Necessary conditions of the model identify optimal trajectories (e.g., simultaneous, single, or cycling controls) that define decision rules and economic thresholds for profit maximizing growers producing crops with aesthetic attributes. The necessary conditions also highlight intertemporal trade‐offs between aesthetic benefits and expected future net benefits of arthropod stocks, which have important policy implications. The model is applied to the greenhouse production system of ivy geranium. 相似文献
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Johannes Woelcke 《Agricultural Economics》2006,34(2):129-139
This article presents a bio‐economic household model, which has been developed to assess the potential impacts of agricultural intensification efforts on economic and ecological indicators in eastern Uganda. A study region in the Lake Victoria Crescent was selected with comparative advantages for intensive agricultural production: high agricultural potential, high market access, and high population density. However, current production is characterized by low input–output systems revealing a discrepancy between development opportunities and actual development outcomes. Based on a farmer participatory research approach, production methods were introduced in the study region aimed at fostering sustainable agricultural development. Data from two community surveys, two comprehensive household and plot level surveys, and farm‐trial data were used to develop and calibrate bio‐economic models for four representative household types. Model scenarios reveal that farm households in eastern Uganda would not pursue sustainable intensification under current socio‐economic conditions. The market environment has to be improved substantially, i.e., transaction and transportation costs have to be reduced, innovative credit schemes for smallholders have to be introduced, and alternative forms of labor acquisition have to be promoted, to provide sufficient economic incentives for the adoption of environmentally sound production methods. In addition, agricultural service provision needs to be reformed and more agricultural research is needed for new and better‐targeted technologies. 相似文献
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Outsourcing in agriculture has traditionally been seen as a managerial strategy of smaller farms to achieve higher levels of efficiency. In this article, we provide empirical evidence supporting the existence of a positive relationship between outsourcing and efficiency in Spanish citrus farming. Outsourcing is measured by the proportion of outsourced labor and capital in farms' total use of these production factors, i.e., the higher the proportion of outsourced inputs, the higher the degree of outsourcing. Making use of data envelopment analysis techniques, we compute input‐specific reductions required to achieve technical efficiency at the farm level. Our results show that attainment of technical efficiency leads to a reduction in the use of both farms' own and outsourced production factors. Furthermore, the degree of outsourcing increases as farms move to their technically efficient productive plans. In addition, outsourcing labor and capital allows farms to achieve efficiency regardless of their size. In our view, this result has a clear implication for policy makers. Instead of trying to improve Spanish citrus farms' competitiveness by pursuing an increase of their average size, policy measures should be adopted to enhance farmers' managerial skills and the efficiency of those external service firms and co‐operatives that are effectively performing basic cultivation tasks. 相似文献
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Anders Skonhoft 《Agricultural Economics》2008,38(2):193-200
A model analyzing the economics of sheep farming is formulated. The basic idea is simple. Sheep are capital and they are held by farmers as long as their capital value exceeds their slaughter, or meat, value. Farmers are therefore portfolio managers aiming to find the optimal combination of different categories of animals. Yields are compared with the yields from other assets. The model is formulated within a Northern Scandinavian economic and biological setting with a crucial distinction between the outdoors grazing season and the indoors season, and with adult sheep and lambs being different categories. In the first step, the management problem is analyzed with only the meat income of the farmers taken into account. In the next step, income from wool production is considered as well. The analysis provides several results that differ from standard harvesting theory. 相似文献
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Robert J. Farquharson Oscar J. Cacho John D. Mullen Graeme D. Schwenke 《Agricultural Economics》2008,38(2):181-192
Soil fertility decline and soil management for crop production are important economic issues for grain growers in north-eastern Australia. In that region, there is evidence of soil fertility decline which is attributed to past crop management practices. The questions addressed in this article are first, whether components of soil fertility can be improved by better management and second, by how much soil fertility would change. Soil fertility for crop production is considered in terms of soil organic carbon and nitrogen. A stochastic dynamic economic analysis of soil fertility management for wheat production is presented. A sequential analysis of first deriving the optimal nitrogen stock and application rates is followed by an assessment of tillage, stubble, and fertilizer strategies to obtain an optimal level of soil organic carbon. The recommended management practices are consistent with emerging management trends in the region. The derivation of optimal levels of soil fertility for agricultural purposes has other policy implications, which we discuss. 相似文献
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This article demonstrates how economic and environmental improvement potentials of Danish pig farms can be estimated using Data envelopment analysis (DEA). To avoid some of the problems associated with the definition of undesirable outputs, environmental variables are included as nutrients applied with manure and nutrients removed with the crops. These environmental variables are combined with a series of economic variables, including the costs of fertilizer. Furthermore, subvector efficiency and a two‐step analysis are used in order to consider economic and environmental (technical) efficiency separately. The empirical results show considerable improvement potentials, especially on the environmental variables. Sensitivity studies validate that these results are robust to possible uncertainties in the measurement of the environmental variables. 相似文献
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This article proposes an extended three‐stage DEA methodology similar to Fried et al. (2002) to improve the measurement of productivity growth when the assumption of free disposability of undesirable output does not apply. A directional distance function is used to construct adjusted Malmquist–Luenberger productivity indexes which simultaneously account for the impacts of undesirable outputs, environmental variables, and statistical noise. Panel data for 263 farmers' credit unions (FCUs) in Taiwan covering the 1998–2000 periods are employed to illustrate the advantages of this method. On average, the productivity of Taiwan's FCUs is found to have deteriorated over the 1998–2000 period. Although an improvement in efficiency has been observed, the major reason for the deterioration is found to be due to the regression of technology. 相似文献
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This article demonstrates how technical efficiency and the impact of environmental regulations of Taiwanese farrow‐to‐finish swine production can be estimated in the presence of undesirable outputs. The issue of measuring technical efficiencies while considering undesirable outputs has been addressed by past studies. But the proper method of including undesirable outputs has always been a subject of debate. This article develops a data envelopment analysis (DEA)‐based model that includes undesirable outputs. The technologies of desirable output production and undesirable output control are considered simultaneously. This allows one to transform undesirable output into desirable output, whereby a traditional Shephard distance function can be used to measure technical efficiencies. An approach to measuring the impacts due to environmental regulations is then derived. Empirical results show that larger farms are more technically efficient than small‐sized farms, but no clear conclusions can be reached for the measures of regulatory impact among farms with different sizes. On average, the sample farms incurred an opportunity cost due to environmental regulations equivalent to 9.8% of market value. Opportunity costs rise with efficiency. 相似文献
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There is growing interest in Nova Scotia's Environmental Farm Plan (NS EFP) program among farmers and policy makers because of several reasons. First, effectiveness of standardized or uniform beneficial management practices in mitigating the negative environmental impacts from agriculture is limited by inherent heterogeneities in agricultural production systems. In addition, there is heightened interest in farmers generating ecological goods and services to society. This study investigates the determinants of participation in the NS EFP program. A discrete choice model of NS EFP participation was applied to a sample of 83 farmers (representing a 31% response rate). To increase relevance of the study to program administrators, the study also examined farmers’ use of various channels and sources of information on farm conservation practices. The most used sources of information on farm conservation practices include a mix of interpersonal sources and government agencies. Although online information (especially those available for free) appears to be gaining popularity in usage, overall, electronic and computer channels of information (especially radio and television) were used less compared with traditional channels of communicating farm conservation information (such as newsletters and agricultural magazines). Regression analysis suggests that farm characteristics (i.e., farm type, farm size, farm income) and farmer capacity variables (i.e., specialized training and knowledge from EFP program information sessions and workshops, and on-farm stewardship demonstrations) were significant determinants of environmental farm planning. 相似文献
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Luis Ambrosio Flores Luis Iglesias Martínez Carmen Marín Ferrer Valero Pascual Gallego Arturo Serrano Bermejo 《Agricultural Economics》2008,38(2):233-245
An area model is presented for agricultural land use, based on a generalized linear mixed model. This model is spatially explicit and dynamic and, although it uses aggregated data, allows for heterogeneity of behavior among individual farmers. The parameters of the fixed component of the model are obtained using an estimation equations approach, and the structure of spatiotemporal correlation is assessed using empirical semivariograms. The model is illustrated using as an example the dynamics of agricultural land use in the Lower Guadalquivir area in Spain. A simulation study indicates that the model gives poor results if the heterogeneity of individual behavior and spatiotemporal autocorrelation are ignored. 相似文献
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Compared to studies evaluating the benefits from agricultural research, there are relatively few empirical studies of the net economic benefits of agricultural extension, and even fewer that consider both public and private sector extension effort. In this study we examine regional differences in the adoption of lupins in Western Australia (WA) in order to estimate the net economic benefits of public and private sector extension. Impacts of extension and other variables on adoption were analysed for 40 shires using multivariate regression analysis. The results suggest that both public and private extension activities influenced farmer uptake of lupins, particularly by bringing forward the start time of the diffusion curve. Economic benefits of extension, based on the statistical analysis, were combined with costs of extension estimated from public sector records and surveys of private sector extension agents and used to estimate the net present value of extension investments by the public and private sectors in the study area. 相似文献
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Being the two largest ethanol producers in the world, biofuel policies in Brazil and the United States affect both their domestic markets and the global food and biofuel economy. In this article we develop a price endogenous mathematical programming model to simulate and analyze the impacts of biofuel mandates and trade distortions on land use, agricultural commodity and transportation fuel markets, and global environment. We find that an 80% increase in total biofuel production from its 103 billion liter baseline level to the mandated 183 billion liter level in 2022 can be achieved with less than 2% increase in total cropland use in both countries. In the United States, this would occur with cellulosic biofuels meeting nearly half of the biofuels consumed and produced largely on cropland pasture and corn ethanol meeting the rest of the mandate and resulting in a 2% increase in corn price. In Brazil, the expansion in sugarcane production would be achieved by reducing land under pasture and a marginal increase in intensification of livestock production. In the aggregate, biofuel policies increase economic surplus in both countries by 1% and redistribute the benefits from agricultural consumers to agricultural producers and the fuel sector. Finally, we also find that full implementation of the mandates in North America, China, and the European Union would reduce the global life‐cycle global greenhouse gas emissions by about 5%. 相似文献
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This article explores how data envelopment analysis (DEA), along with a smoothed bootstrap method, can be used in applied analysis to obtain more reliable efficiency rankings for farms. The main focus is the smoothed homogeneous bootstrap procedure introduced by Simar and Wilson (1998) to implement statistical inference for the original efficiency point estimates. Two main model specifications, constant and variable returns to scale, are investigated along with various choices regarding data aggregation. The coefficient of separation (CoS), a statistic that indicates the degree of statistical differentiation within the sample, is used to demonstrate the findings. The CoS suggests a substantive dependency of the results on the methodology and assumptions employed. Accordingly, some observations are made on how to conduct DEA in order to get more reliable efficiency rankings, depending on the purpose for which they are to be used. In addition, attention is drawn to the ability of the SLICE MODEL, implemented in GAMS, to enable researchers to overcome the computational burdens of conducting DEA (with bootstrapping). 相似文献