大武岩溶水源地地下水水化学特征及其影响因素

选取北方典型岩溶裂隙含水系统,利用水文地球化学方法和统计学方法分析其地下水水化学特征及其影响因素,结果表明:沿着地下水主径流路径,地下水水化学类型种类逐年增加,除水岩作用外影响水化学类型的Ca~(2+)、Cl~-、Na~+、SO_4~(2-)多来源生活污水、工业废水和生活垃圾,且地下水中挥发性有机污染物的检出及NO_3~-、VOCs时空输入的多变性,表明区内地下水水化学持续受到人类活动的影响;利用比例系数法和因子分析法等获知影响地下水水化学的主要过程为水岩相互作用、阳离子交替吸附作用及溶滤作用,综合分析水化学类型和聚类分析可解译出监测点接收的物质组分及来源、地下水水化学动态变化过程及影响因素。     

辽宁省玉米水分生产率时空变化规律及影响因素

基于 2005- 2017 年辽宁省 14 个地级市玉米种植数据、灌溉用水量及气象数据等资料, 运用线性倾向估计及全局空间自相关分析等方法, 从不同地区、不同降水年型( 枯、平、丰) 角度出发, 分析不同玉米水分生产率指标的时空变化规律及其影响因素, 结果表明: 在时间尺度上, 全省玉米灌溉水分生产率多年平均值为 11 63 kg / m3 , 玉米水分生产率总体每 10 a 以 01 04 kg/ m3 的速率波动上升; 在空间尺度上, 全省玉米灌溉水分生产率均值呈现出西北 高、东南低的空间分异, 玉米水分生产率在枯水年( 2006) 和平水年( 2007) 总体均表现为东北高、西南低, 而丰水年 ( 2012) 则表现为西北高、东南低; 玉米单产量是影响各水分生产率指标最显著的因素。该研究成果可为提高辽宁省农业用水效率、缓解水资源压力提供一定参考。     

How to Discount Cashflows with Time-Varying Expected Returns

While many studies document that the market risk premium is predictable and that betas are not constant, the dividend discount model ignores time‐varying risk premiums and betas. We develop a model to consistently value cashflows with changing risk‐free rates, predictable risk premiums, and conditional betas in the context of a conditional CAPM. Practical valuation is accomplished with an analytic term structure of discount rates, with different discount rates applied to expected cashflows at different horizons. Using constant discount rates can produce large misvaluations, which, in portfolio data, are mostly driven at short horizons by market risk premiums and at long horizons by time variation in risk‐free rates and factor loadings.     

论中国现代管理理论的核心范畴

核心范畴是指既能够客观反映某一理论体系概念链条的本质内容,又能够充分体现该理论体系的特征、过程及其趋势的基本理论概括.完整的理论体系,不仅有相对独立的一般范畴系列,形成具有内在逻辑性的范畴链条,而且有反映该特定理论体系本质内容的核心范畴.管理在实践中行为要科学,理论上范畴要科学,阐释时结构与体系要科学,包括理论的发展与创新也要科学.科学化既是中国现代管理理论的要求、特征、逻辑与归宿,也是中国现代管理理论的体现、实现与生命.     

SAVINGS MOBILIZATION,FINANCIAL DEVELOPMENT AND LIBERALIZATION: THE CASE OF MALAYSIA

This paper attempts to identify the key factors behind Malaysia's remarkable savings performance. Drawing on the life cycle theory, the saving function is estimated by incorporating other relevant structural features and institutional settings of the Malaysian economy into the specification. Particular emphasis has been placed on the roles of financial factors in mobilizing funds in the private sector. The results suggest that financial deepening and increased banking density tend to encourage private savings. Development of insurance markets and liberalization of the financial system, however, tend to exert a dampening effect on private savings.     

跨国公司在营销中的转移定价策略

随着全球经济一体化趋势的发展,跨国公司已经成为当今世界经济活动的主体,跨国公司内部贸易的定价机制,尤其是转移价格,成为跨国公司经营中最具诱惑力的商业秘密武器.     

关于中国现代经济理论的基本问题

中国现代经济理论是辛亥革命以来关于振兴中华、富民强国的一系列经济观点、思路、理论及学说的总和,是在中国国情与社会发展的基础上学习并借鉴西方经济理论与发展经验,以追求并实现现代化为核心内容的具有中国风格和中国特色的经济理论体系。深刻理解与把握中国现代经济理论的涵义、性质、任务、分期、构成以及研究的基本问题,对于进一步完善中国现代经济理论的学科建设和深刻理解中国特色社会主义的理论与实践至关重要。     

清苑县南水北调配套工程运行风险评价

南水北调配套工程运行风险评估体系属于复杂的系统问题,其模糊性在评估中应予以考虑。基于模糊识别理论,采用非线性模型对清苑县南水北调配套工程运行风险进行评价。结果表明,清苑县南水北调配套工程运行风险等级介于2级与3级之间,略偏于2级,属于低风险等级。评价过程与评价结果不仅可为清苑县南水北调配套工程的安全管理提供参考意义,而且表明非线性模型在南水北调配套工程运行风险评价中具有良好的适用性。     

Return,Risk, and Yield: Evidence from Ex Ante Data

The purpose of this study is to investigate the relationship between return and yield in the context of ex ante data from The Value Line Investment Survey and by examining the role of dividends as a proxy for risk. The use of ex ante data should substantially reduce the confounding of tax and information effects that has affected earlier studies. Heteroscedasticity is detected in the after-tax CAPM and found to be negatively related to yield and positively related to beta. Maximum likelihood methods are used to correct for heteroscedasticity and generate efficient coefficient estimates. Using data for each of the years 1973 through 1983, there is an overall positive relationship between expected return and yield. However, coefficient estimates of yield are highly variable from year to year.     

The Joint Cross Section of Stocks and Options

Stocks with large increases in call (put) implied volatilities over the previous month tend to have high (low) future returns. Sorting stocks ranked into decile portfolios by past call implied volatilities produces spreads in average returns of approximately 1% per month, and the return differences persist up to six months. The cross section of stock returns also predicts option implied volatilities, with stocks with high past returns tending to have call and put option contracts that exhibit increases in implied volatility over the next month, but with decreasing realized volatility. These predictability patterns are consistent with rational models of informed trading.