Bioenergy Crop Production in the United States: Potential Quantities, Land Use Changes, and Economic Impacts on the Agricultural Sector

The U.S. Departments of Agriculture and Energyjointly analyzed the economic potential for,and impacts of, large-scale bioenergy cropproduction in the United States. Anagricultural sector model (POLYSYS) wasmodified to include three potential bioenergycrops (switchgrass, hybrid poplar, and willow). At farmgate prices of US $2.44/GJ, anestimated 17 million hectares of bioenergycrops, annually yielding 171 million dry Mg ofbiomass, could potentially be produced at aprofit greater than existing agricultural usesfor the land. The estimate assumes highproductivity management practices are permittedon Conservation Reserve Program lands. Traditional crops prices are estimated toincrease 9 to 14 percent above baseline pricesand farm income increases annually by US $6.0billion above baseline.At farmgate prices of US $1.83/GJ, anestimated 7.9 million hectares of bioenergycrops, annually yielding 55 million dry Mg ofbiomass, could potentially be produced at aprofit greater than existing agricultural usesfor the land. The estimate assumes managementpractices intended to achieve highenvironmental benefits on Conservation ReserveProgram lands. Traditional crops prices areestimated to increase 4 to 9 percent abovebaseline prices and farm income increasesannually by US $2.8 billion above baseline.     

Labor income and risky investments: can part-time farmers compete?

In the developed countries, a majority of farm households receive at least as much income from nonfarm sources as from the farm. Such part-time farms have survived inspite of lower returns than full-time farms. This paper considers when lower returns to part-time farming could be compensated by risk-reduction due to diversification of income sources. The paper uses a dynamic portfolio choice model with labor income. The model and results could be applied in other contexts as well.     

区别对待收入分配领域的正常差距和分配不公

当前收入分配领域存在的主要问题是收入分配不公.收入分配中的正常差距在社会主义市场经济体制下是发展的动力,必须予以承认.对于违反了社会公平原则、损害了经济和社会和谐发展的非正常收入差距,需要政府在广泛听取人民群众呼声的前提下及时制定和修改相关的法律法规,从制度上保证分配正义和公民利益.     

Chronic Diseases, Labor Supply and Medical Expenditure at Older Age: Evidence from China

China has undergone a rapid epidemiological transition from infectious diseases to chronic diseases. Using data from the China Health and Retirement Longitudinal Study (CHARLS), this paper documents the profile of chronic diseases among older Chinese people, estimates the impact of the onset of chronic diseases on the labor supply, and examines the correlation between the prevalence of chronic diseases, a household’s medical expenditure and the role of health insurance in reducing medical costs. Empirical results show that the prevalence of chronic diseases is extremely high among older Chinese people and increases sharply with age. We find significant negative effects from the onset of chronic diseases on an individual’s livelihood at work. The estimation results by age and education suggest that the labor supply of the older and more highly educated people is more sensitive to the onset of chronic diseases. We also show that there can be a substantial indirect loss of individual and household income due to the onset of chronic diseases by limiting the labor supply. We find that the prevalence of chronic diseases is significantly associated with higher out-of-pocket medical expenditure. The reduced-form estimation results suggest that people with insurance have lower medical expenditure caused by minor chronic diseases, but this is only the case for women and urban residents. However, health insurance contributes little in reducing medical expenditure caused by major chronic diseases.     

高速公路工程不动产价值的动态收益还原法研究

本文分析了高速公路工程不动产的经营收益构成和运营成本构成,应用随机时间序列模型和工程不动产评估理论建立了高速公路工程不动产的净经营收益动态预测模型和还原率动态预测模型,为实现公路工程不动产价值的传统经验静态评估提升及科学动态评估奠定基础。     

我国茶产业全要素生产率增长及其分解--基于随机前沿生产函数的分析

文章利用超越对数的随机前沿生产函数,测算了1996-2007年我国茶产业的全要素生产率。研究表明：研究期间我国茶产业TFP平均增长0.70%,平均技术进步率为1.42%,平均技术效率为72.05%,但都呈逐步下降趋势; TFP增长的主要来自技术进步,但技术效率的变化和规模报酬率出现一定的退步,阻碍TFP的增长;各省份TFP增长有差异,其中四川省的TFP增长速度最快,而湖南省和陕西省的TFP成负增长;我国茶叶的劳动产出弹性逐年增大,而资本产出弹性逐渐变小,且我国茶叶生产一直处于规模报酬递减状态。     

我国收入贸易条件变动分析:1995～2004

收入贸易条件衡量的是一国在国际分工中获得的总体贸易利益的多少,在对我国贸易条件的变化进行分析时应当合理考虑收入贸易条件指数的变动。近年来我国的收入贸易条件指数呈现出持续改善的趋势,这表明外贸规模的扩大对国民经济发展做出了积极的贡献,仅仅根据商品贸易条件指数下降而得出我国贸易条件出现严重恶化的结论缺乏充分的根据。从国际经济竞争的现实背景来考虑,我国应当在保持收入贸易条件指数不恶化的情况下,继续大力推动出口贸易量较快地增长。     

基于公平偏好理论的锦标机制研究

在完全竞争的劳动力市场和产品市场中，分析了公平偏好的员工是同质和异质两种情况下，最优锦标机制的设计及效率问题。研究表明，公平偏好锦标赛模型比传统锦标赛模型更具一般性。     

人力资本对非农就业收入的影响——基于村庄内外的视角

利用山西省2004年3 506名农村居民的抽样调查数据,比较分析了人力资本对劳动力村内、村外非农就业收入的影响。在进行OLS估计,考虑到可能出现的选择性偏误,使用Heckman二阶段模型进行纠正后发现,无论是在村内还是在村外,受教育年数对非农就业收入均有显著的正向影响;受过职教培训与劳动力村内非农就业收入具有显著的负向关系,但其对村外非农就业收入的促进作用却十分明显;拥有技术职称在村内取得了显著的收入回报;健康对于村内非农就业收入的影响并不十分明显,但在村外,健康成为重要的影响变量。     

我国地区间的财力差异——基于地方税体系与转移支付体系的比较分析

和谐社会的建设客观上要求各地居民享有相对均等的公共服务水平,各地公共服务水平的差异主要是由以财政支出量为指标的财力差异决定的。我们测算了地方税收入各项目和转移支付体系各项目对地区间财政支出差异的相对贡献,以期为缩小地区财力差异和优化财政转移支付体系结构提供科学依据。