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41.
基于ELES模型的中国城镇居民食品消费结构实证分析   总被引:1,自引:0,他引:1  
基于ELES模型,利用2012年31个省份城镇居民家庭人均可支配收入和食品消费支出数据,对中国城镇居民食品消费结构情况进行研究,回归得到各类食品的边际消费倾向、收入弹性和自价格弹性。研究表明,城镇居民食品消费边际倾向中,在外用餐最高,其次为水产品、肉禽及制品;水产品、糕点类、在外用餐类的需求增长率高于收入增长率;蔬菜、粮食、肉禽及制品等基本食品消费的自价格弹性较低,水产品、糕点类、外出用餐的自价格弹性较高。  相似文献   
42.
许可实施是植物品种权实施的主要模式之一,是将创新品种转化为利润的重要机制,能够激励植 物新品种研发创新,并促进新品种技术扩散。植物品种权许可实施不同于品种权转让,具有收入效应和竞 争效应,从微观角度可以提高知识资产的使用效率。但是植物品种权许可实施的收入效应和竞争效应受复 杂因素影响,由于信息不对称和不确定因素的存在,许可双方无法事先签订完美的许可合同。品种权人可 以通过许可合同价格条款和许可范围的选择,利用“入门费 分期提成/阶段性支付”的许可费用模式, 规避许可风险。  相似文献   
43.
《Southern Forests》2013,75(4):303-309
Global demand for treating prostate disorders with Prunus africana bark extract has made P. africana Africa's largest medicinal plant export. Unsustainable harvesting practices can lead to local extirpations of this multipurpose tree. Survey research targeting P. africana harvesters in a Tanzania forest reserve revealed that 78% of them used unsustainable harvesting practices. This research focused on establishing a socioeconomic profile of the harvesters, the profitability of their business operations, and identifying the factors that influence their selection of harvesting practices. Results indicate that harvesters have above-national-average education, double the average family size, and generate income exceeding government's minimum wages. Large family size and high earning potential imply increased future harvesting activity. Logistic regression results indicate that education and training level could predict the likelihood that a harvester would use unsustainable harvesting practices. Local- and district-level government organisations could implement a resource assessment as a basis to design and implement harvesting schedules and ensure that the harvesters receive appropriate training, regardless of their education level.  相似文献   
44.
通过改进的索洛模型,对建国以来我国农业经济政策与粮食主产区农民增收发展的历史与现状进行了实证。结果显示:农业经济政策制定与实施力度的直接贡献度与粮食主产区农民增收成正相关关系,在此基础上提出相应耦合机制的政策建议。  相似文献   
45.
以1985—2003年安徽省农业统计资料为样本,采用定性分析与定量分析相结合的研究方法,建立安徽省农业投资与安徽省农业经济增长的计量经济模型,并在此基础上提出了增加安徽农业投资,加快安徽农民收入增长的对策。  相似文献   
46.
Economic growth and income distribution are two of the major subjects in international economic studies. Perforce theory believes that inequality improve growth. Endogenous economic growth theory shows that inequality is harmful for growth. After summarizing western theory on growth and income distribution, this paper gives the detail survey of relationship between income distribution and growth, and the mechanism of the effect is discussed.  相似文献   
47.
Reviews     
《Asia Pacific viewpoint》2002,43(2):253-266
Book reviewed in this article: Winston Halapua, Living on the fringe: Melanesians of Fiji Patrick Fuery and Nick Mansfield, Cultural Studies and Critical Theory Keith Chambers and Anne Chambers, Unity of Heart. Culture and Change in a Polynesian Atoll Society Alice Aruhe’eta Pollard, Givers of Wisdom, Labourers without Gain: Essays on Women in Solomon Islands Prema–chandra Athukorala, Chris Manning and Piyasiri Wickramasekara, Growth, Employment and Migration in Southeast Asia: Structural Change in the Greater Mekong Countries Edvard Hviding and Tim Bayliss–Smith, Islands of Rainforest: Agroforestry, Logging and Eco–tourism in Solomon Islands  相似文献   
48.
This study aimed to investigate a cultivar selection criterion based on income ha−1 in common wheat. Regional yield trials with 20 entries were planted in Diyarbakır, Hazro and Ceylanpınar in southeast Anatolia in the 2004/2005 growing season. A randomized complete block design with four replications was employed. Grain samples from each location were subjected to quality analyses, and then presented to randomly selected grain purchasers with the local commodity market for market price estimations. Entries 1, 9, 10, 7 and 6 were the top five ranking entries for grain yield, giving 5,320, 5,290, 5,280, 5,140 and 5,130 kg ha−1, respectively. From the market price perspective, entries 17, 3, 7, 20 and 8 received the five highest marketing price offers with the values 239.0, 238.1, 237.1, 236.9 and 236.7 US$ tonne−1, respectively. There was a US$ 10.94 tonne−1 market price difference between entries with the highest and the lowest market price. The only quality analyses showing significant correlations with market price were Zeleny sedimentation value and hectolitre weights (kg hl−1). From thev production income [= marketing price (US$ tonne−1) × grain yield (kg ha−1)] point of view, entries 9, 10, 1, 7 and 6 were ranked from 1st to 5th for production income ha−1 with the values 1,241.0, 1,238.0, 1,219.9, 1,214.2 and 1,209.3 US$ ha−1, respectively. All five high yielding entries were also high-income entries. A rank stability analysis further indicated that entry numbers 6, 7, 8, 4 and 1 stable for high production income ha−1. A simulation study, based on allocation of additional premiums for high quality indicated that entries 9,1,10, 7, and 6 would be top ranking for high income ha−1 if given an additional premium of as much as twice the standard deviations of market price for each entry (the highest premium limit; 20.24 US$ tonne−1). The order for cultivar preference for high production income ha−1 would change and would generate 1,321.94, 1,296.20, 1,281.11, 1,258.06 and 1,243.01 US$ ha−1, respectively. It was concluded that the relatively quality conscious Şanlıurfa commodity market does not offer adequate premiums for the high quality grains. This results in farmer preference for high yielding lower quality cultivars. Even though quality cannot be neglected, and cultivar preference could change with additional premiums, breeders must give more attention to high production income ha−1.  相似文献   
49.
Improving national average income and reducing regional income inequality often serve as dual goals of economic development in a country. After over twenty years of economic reforms, China has been fairly successful in achieving the first goal, but failed in the second. This paper uses recent data with a sharper resolution to examine the variation of average wages across Chinese cities 1989–1997. Widening wage inequalities across cities are observed during the period. This research also seeks to explain the variation of wages between cities by factors such as agglomeration (density and city size), location advantages (distances from central cities and from the coastline), educational attainment, industrial structure and administrative hierarchy. Many of the factors are found to be important in explaining wage differences in Western countries but are yet to be tested in China. Some factors such as distance from the coast, industrial structure and administrative hierarchy are considered because of China’s unique social and economic systems.  相似文献   
50.
收益还原法是农用地估价中的常用方法,但是目前利用此法评估农用地地价时,采用实际纯收益代替预期纯收益而导致评估的地价不合理。该文系统地论证了利用灰色系统建模来预测农用地预期纯收益的可行性,并分析了整个建模过程。最后将模型应用到湖北省武穴市农用地估价中。结果表明,应用此模型预测的后验差比值为0.21,小误差频率为1,精度达到一级。利用预测得到的预期纯收益来评估农用地地价与传统方法相比更趋合理,具有实际的应用价值。  相似文献   
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