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Impact assessment studies consistently show that the benefits generated by plant breeding are large, positive and widely distributed. Numerous case studies have concluded that investment in plant breeding research generates attractive rates of return compared to alternative investment opportunities, that welfare gains resulting from the adoption of modern varieties (MVs) reach both favoured and marginal environments, and that benefits are broadly shared by producers and consumers. But just how reliable are the results of studies that estimate the benefits of plant breeding research? This article reviews methods used to estimate the benefits of plant breeding research and discusses theoretical and empirical issues that often receive inadequate attention in applied impact assessment work. Our objective is not to question the validity of the theoretical frameworks commonly used to estimate the benefits of plant breeding research, but rather to examine problems that can arise when the widely accepted theoretical frameworks are used for empirical analysis. Most of these problems can be grouped into three basic categories: (1) problems associated with measuring adoption and diffusion of MVs, (2) problems associated with estimating benefits attributable to adoption of MVs, and (3) problems associated with assigning credit among the various plant breeding programmes that participated in developing the MVs. 相似文献
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Buysse Jeroen; Fernagut Bruno; Harmignie Olivier; de Frahan Bruno Henry; Lauwers Ludwig; Polome Philippe; Van Huylenbroeck Guido; Van Meensel Jef 《European Review of Agricultural Economics》2007,34(1):21-52
A mathematical programming model, calibrated on individual farmdata, is used to analyse the reform of the common market organisation(CMO) in the sugar sector of the European Union. The model includesa precautionary farm supply function for out-of-quota sugarbeet that is estimated as part of a simultaneous system of first-orderconditions. Simulation results from a sample of Belgian sugarbeet farms show that the sugar CMO reform induces differentsupply and income effects across farms depending on their shareof out-of-quota sugar beet relative to their total beet supplyand their quota rent. A further cut in the minimum price ofsugar beet initiates structural change in the farm sector. 相似文献
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Returns to research are thought to be robust under alternative supply elasticity assumptions. We show, both conceptually and numerically, how advances in approximating social benefits make returns to research sensitive to the supply elasticity. Despite this greater sensitivity, these advances retain conceptual and practical advantages. We make recommendations for dealing with the increased sensitivity. 相似文献
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The successive reforms of the Common Agricultural Policy (CAP), the enlargements of the European Union (EU) and the impacts of climate change have amplified the diversity of European agriculture. These rapid changes have resulted in the intensification of agricultural activities in some regions, while they have led to the marginalization of agriculture and its eventual abandonment in others. The objective of this paper is to investigate the factors that are behind the differential performance of agriculture across the EU-27 countries. Ward's, k-means and two-step clustering methods were used to classify European agriculture based on gross-value-added farm, land and labour productivity indicators. Significant differences were revealed between the Northern-Central counties and the continental peripheries (Mediterranean, Eastern, Northern Scandinavian). An exact logistic regression model was used to analyse the factors behind this differential performance. Agricultural sectors characterized by a young and better trained farm population are more likely to attain high economic performance. The odds to attain high economic performance are almost 9 times greater for countries with a highly trained farm population, namely, the Netherlands (72%) and Germany (69%), than for countries with poor farm training, while an ageing farm population such as in Portugal (72%) and Bulgaria (66%) is 92% less likely to be high performing. The importance of investments in agriculture was also identified. The significance of the wheat yield variable highlights the importance of both environmental conditions and technical efficiency on farm economic performance. Similarly, countries with a high share of utilized agricultural land in less favoured areas, such as in the Mediterranean, are 94% less likely to attain high economic performance. The redesign of CAP direct payments between old and new member states after 2013 combined with the impacts of agricultural trade liberalization and climate change are expected to deteriorate the position of low performing agricultural sectors further. 相似文献
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本文采用变系数生产模型,将全要素生产率中涉及各生产要素质量提升的部分剥离,从而识别财政支出通过不同途径影响农业增长的内在机制,并利用省级面板数据(1978-2015年31个省份)和县级面板数据(1993-2010年2495个县),从宏观和中观视角实证考察和比较了各改革阶段财政支出通过不同途径对农业产出的影响及其长期总体... 相似文献
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Osman Orkan Özer 《国际粮食与农业综合企业市场学杂志》2015,27(2):91-99
Variations in producer prices over time cause constant fluctuations in farm incomes. In this study, the author uses a game theory approach to determine the economically optimal time to sell dried figs for the agricultural firms that produce them. Based on the price producers received in the period between August 2003 and July 2010, dried fig prices were converted into 2003 real price levels. According to a linear programming model based on these assumptions, it was determined that the best time for producers to sell dried figs, with the rate of 26.63%, was November and December. 相似文献
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Graeme J. Doole Alvaro J. Romera 《The Australian journal of agricultural and resource economics》2014,58(3):471-494
Nutrient emissions from pastoral agriculture are a global cause of declining water quality. Their management is complicated through variability arising from climate and soil influences. This paper compares the implications of input‐based policies and direct restrictions on leaching to achieve 10 and 20 per cent reductions in nitrogen (N) load, in the context of pasture‐based New Zealand dairy farms. The most important mitigation practices on these farms are de‐intensification (involving reductions in N fertiliser application and stocking rate) and the application of nitrification inhibitors. A stylised conceptual model, incorporating both sources of variability, is used to identify the implications of alternative policies. Direct restriction of estimated N leaching is the most cost‐effective policy to reduce N leaching by 10 and 20 per cent. These results indicate the general insufficiency of input‐based mechanisms for water quality improvement, given the low correlation between input use and leaching, possible substitution with unrestricted inputs and their failure to motivate the use of mitigation strategies. Additionally, model output indicates that inherent variability in water quality, mainly due to climate influences, can dominate the benefits of regulatory action in any given year. 相似文献
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This empirical study uses 100 years of annual data on 11 agricultural commodities from Belgium to measure the impact of structural changes coinciding with economic development and changes in political institutions on agricultural protection. The analysis shows that changes in agricultural protection are caused by a combination of factors. Governments have increased protection and support to farmers when world market prices for their commodities fell, and vice versa, offsetting market effects on producer incomes. Other economic determinants were the share of the commodities in total consumer expenditures (negative effect) and in total output of the economy (positive effect). With Belgium a small economy, there was no impact of the trade position. Changes in political institutions have affected agricultural protection. Democratic reforms which induced a significant shift in the political balance towards agricultural interests, such as the introduction of the one‐man‐one‐vote system, led to an increase in agricultural protection. The integration of Belgian agricultural policies in the Common Agricultural Policy in 1968 coincided with an increase in protection, ceteris paribus. Both institutional factors, related to changes in access to and information about the decision‐making at the EU level, and structural changes in the agricultural and food economy may explain this effect. 相似文献
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邝奕轩 《国土与自然资源研究》2011,(2):95-96
农业的重要地位在海南省十分明显,农业面源污染成为海南省重要的环境问题.通过分析海南省农业面源污染形成途径,建立海南省农业面源污染的评价指标,对海南省农业面源污染做出总体判断.从政策体系、污染治理的综合评价指标体系、激励机制和政府行政管理与公民参与机制四个角度提出了海南省农业面源污染治理的对策. 相似文献
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Measuring Farm and Market Level Economic Impacts of Improved Maize Production Technologies in Ethiopia: Evidence from Panel Data 总被引：1，自引：0，他引：1 
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下载免费PDF全文 Menale Kassie Paswel Marenya Yohannis Tessema Moti Jaleta Di Zeng Olaf Erenstein Dil Rahut 《Journal of Agricultural Economics》2018,69(1):76-95
While it is often recognised that agricultural technology adoption decisions are intertwined and best characterised by multivariate models, typical approaches to examining adoption and impacts of agricultural technology have focused on single technology adoption choice and ignored interdependence among technologies. We examine farm‐ and market‐level impacts of multiple technology adoption choices using comprehensive household survey data collected in 2010/11 and 2012/13 in Ethiopia. Economic surplus analysis combined with panel data switching endogenous regression models are used to compute the supply shift parameter (K‐shift parameter), while at the same time controlling for the endogeneity inherent in agricultural technology adoption among farmers. We find that our improved technology set choices have significant impacts on farm‐level maize yield and maize production costs, where the greatest effect appears to be generated when various technologies are combined. The change in maize yield and production costs results in an average 26.4% cost reduction per kilogram of maize output (the K‐shift parameter). This increases the producer and consumer surpluses by US$ 140 and US$ 105 million per annum, respectively. These changes in economic surplus help to reduce the number of poor people by an estimated 788 thousand per year. We conclude that deliberate extension efforts and other policies that encourage integration of technologies are important for maize technologies to yield their full potential at both farm and market levels. 相似文献
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Agricultural land conversion for urban development is a major process in the vicinity of many cities in Vietnam. This causes problems for the fabric of local society. In this paper, we evaluate four agricultural land’s acquisition projects in two areas (Hoai Duc district and Thanh Oai district) in Hanoi, Vietnam to examine two primary questions: (1) how do farmers obtain any economic benefit from urban development projects? And, (2) how are socio-economic livelihoods of the farmers effected by land conversion? The investigation relied on a market land price's survey using a structured-interview method, in which 395 land-acquired households were randomly selected. The responses indicate that there are unequal benefits among the various stakeholders. On average farmers tend to benefit the least. Although the farmers have the possibility to transform their agricultural livelihood into a non-agricultural one with probably a higher income, they are actually faced with many difficulties in maintaining non-agricultural activities, in finding stable alternative livelihood activities, and in using the compensation for investments. 相似文献
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Jinyang Cai Weiqiong Chen Jikun Huang Ruifa Hu Carl E. Pray 《Journal of Agricultural Economics》2020,71(2):287-304
China’s research and development (R&D) policy has changed considerably over recent decades, and great changes occurred in 2006 when the main programme objective of China’s R&D changed from the 863 Programme and 973 Programme to the National Science and Technology Major Project. One topic that has drawn extensive attention is whether the investment reform improved R&D productivity in China. Using a unique panel dataset from 160 universities, this paper examines the effect of the investment reform on productivity improvement in China’s agricultural biotechnology sector. We use a panel count data model with a dynamic feedback mechanism to model the knowledge production process. Strong evidence indicates that the investment reform greatly contributes to knowledge output production in China’s agricultural biotechnology sector. We also find that the input quality is more important than the absolute quantity; human research capacity exhibits the greatest contribution to the output of patents; past knowledge accumulation helps produce more patents; and entry barriers to patent production exist in China’s agricultural biotechnology sector. Moreover, the patent explosion in China may have been largely caused by improvements in the human capital input quality. 相似文献
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在二十世纪三十年代前期实行统制经济和救济农村金融的背景下，国民政府和各省政府、社会团体、银行机构以及一些大学广泛开展了棉花产销合作运动，陕西棉花产销合作是其中办理较早、规模最大、成绩较好的地区。由于各方的努力，陕西棉花产销合作取得了一定的成绩，棉花品种得到改良，棉田面积扩大，棉农因此获得了一定的利益，但棉花产销合作也存在诸多缺陷，面临许多困境，前景仍然十分艰难。 相似文献
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Lilli Aline Schroeder Alexander Gocht Wolfgang Britz 《Journal of Agricultural Economics》2015,66(2):415-441
We extend the Common Agricultural Policy Regionalised Impact Modelling System (CAPRI) with a regional computational general equilibrium (CGE) model to estimate the effects of the Pillar II of the Common Agricultural Policy. Our aim is to assess the modeling approach by comparing the scenario results with observations from the evaluation reports for rural development, supplemented with expert interviews and findings from the literature. For this purpose, an ex‐post scenario is developed for Germany that models the effect of the Pillar II measures in 2006. We observe a moderate impact, namely, an increase in agricultural income (5%) and agricultural land use (0.15%), particularly grassland, and a substitution of arable land with grassland. This effect leads to a total increase in agricultural production, particularly of beef, and to an increase in total greenhouse gas emissions and total nitrogen surplus for Germany. Greenhouse gas emissions and nutrient surpluses per ha, however, are reduced. We observe that farm investment programmes displace private investment. The evaluation reports confirm the moderate impact and our major results, as does the comparison with other literature. However, the conclusions about agri‐environment measures and their impact on income differ. The most important difference between our results and the evaluation reports and majority of the present literature is that we also quantify the joint effect between the whole economy and policy measures, with some contradictory effects. 相似文献
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Johan F.M. Swinnen Harry de Goter Gordon C. Rausser Anurag N. Banerjee 《Agricultural Economics》2000,22(2):111-122
The paper tests a political economy theory of simultaneous government decision‐making on income redistribution through commodity policies and on public research investment in agriculture. We use data from 37 countries on agricultural protection and public agricultural research expenditures (PARI). The empirical results are consistent with the political economy hypotheses. The analysis suggest that structural changes in the economy have important effects on the political incentives for governments not only to subsidize or tax farmers, but also to invest in public agricultural research. Furthermore, the analysis supports the hypotheses that the impact of such structural changes on government decision‐making on PARI is non‐linear and conditional on other factors. Regarding the impact of political institutions, the results suggest that more democracy neither leads to more distortionary transfers (agricultural protection), nor to lower investment in public goods (PARI). ©2000 Elsevier Science B.V. All rights reserved. 相似文献
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This article has two goals. The first is to extend previous results regarding calibration of land‐constrained programming models of agricultural supply against supply elasticities to the general case of multiple constraints. The second goal is to demonstrate how the resulting calibration conditions can be used as a source of identification to disaggregate crop supply elasticities down to the level at which static information on acreage allocations is available. We propose an information‐based disaggregation algorithm to systematically generate regionalised elasticities from a single prior, and provide an empirical illustration. 相似文献
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Farmers are those who daily supervise and manage rural areas, but still their collaborations with those institutions entitled to decide the transformation of these territories are not managed properly. The experiences of participatory processes with the involvement of farmers are analyzed in many agricultural studies. A systematic review has allowed us to analyse experiences related to 35 participation paths aimed at rural regions’ development. The analysis has been made on the basis of 14 variables describing the path followed and its purpose, the agricultural holding involved and the areas surveyed.The work has the objectives to identify some strengths and weaknesses in the involvement of farmers in decision-making and the strengths and weaknesses of the processes themselves. The review has shown that too often in participatory processes farmers are considered only as a source of information to be used by researchers rather than as active participants in the choices for the protection, management and transformation of the rural territory. An effective participatory rural appraisal requires greater empowerment of farmers. In general, compared to the methods and tools used, farmers are wary of paths that are too complex and prefer the use of low-tech tools. This result can be attributed to the farmers’ demand of direct contact with the researchers to build trust and also to the average age of European farmers, which is pretty high.In participation contexts, it is not possible to establish standardized methods and tools, because each process should be tailored for the community that expresses it. Nevertheless, the work has highlighted the need to establish some minimum principles to avoid considering unsuccessful some participation paths which, in reality, have been only scarcely participated. In the work, these principles have been presented through the development of key questions, to which those who design the path for an effective engagement of agricultural stakeholder must respond: representativeness, empowerment, empirical knowledge, relationships, group type, numerosity and involvement stage. 相似文献
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Jean‐Daniel Rinaudo Javier Calatrava Marine Vernier De Byans 《The Australian journal of agricultural and resource economics》2016,60(3):422-441
This paper proposes a system of tradable Water Saving Certificates to improve the efficiency of water allocation between Drinking Water Utilities at river basin level. A market institutional set‐up, inspired from recent policy developments in the energy sector, is proposed. An original analytical price‐endogenous model is developed to simulate trade intensity, equilibrium price and efficiency gains in this urban water market. The economic model is implemented in a French case study using mathematical programming. It is used for conducting an ex‐ante evaluation of trade possibilities and efficiency gains, considering different spatial restrictions aimed at controlling environmental externalities. Our modelling exercise provides evidence of the benefits of the proposed Water Saving Certificate scheme. 相似文献