A Semiparametric Method for Valuing Residential Locations: Application to Automated Valuation

This paper is motivated by automated valuation systems, which would benefit from an ability to estimate spatial variation in location value. It develops theory for the local regression model (LRM), a semiparametric approach to estimating a location value surface. There are two parts to the LRM: (1) an ordinary least square (OLS) model to hold constant for interior square footage, land area, bathrooms, and other structural characteristics; and (2) a non-parametric smoother (local polynomial regression, LPR) which calculates location value as a function of latitude and longitude. Several methods are used to consistently estimate both parts of the model. The LRM was fit to geocoded hedonic sales data for six towns in the suburbs of Boston, MA. The estimates yield substantial, significant and plausible spatial patterns in location values. Using the LRM as an exploratory tool, local peaks and valleys in location value identified by the model are close to points identified by the tax assessor, and they are shown to add to the explanatory power of an OLS model. Out-of-sample MSE shows that the LRM with a first-degree polynomial (local linear smoothing) is somewhat better than polynomials of degree zero or degree two. Future applications might use degree zero (the well-known NW estimator) because this is available in popular commercial software. The optimized LRM reduces MSE from the OLS model by between 5 percent and 11 percent while adding information on statistically significant variations in location value.     

集值函数及向量值函数的两类线性算子逼近

本文得到了利用插值型线性算子列及积分型算子列逼近连续集值函数及连续向量值函数的收敛逼近阶。     

未确知有理数的定义运算及其应用

本文给出未确知有理数的定义、运算。并把它应用到煤矿立井建设中,为矿井施工管理提供了可靠的数学处理方法。     

Dynamic analysis of stock return volatility in an integrated international capital market

This paper examines the dynamic behavior of the stock return volatility for Canada, Japan, Germany, and the United Kingdom. The evidence indicates that international stock return volatility is mainly influenced by the U.S. stock return volatility and the exchange rate volatility, supporting the international capital market integration hypothesis. There seems to be some correlation between stock return volatility and macroeconomic volatility, but the effect is relatively weaker. In addition to the economic fundamentals, the noise component is found to be time varying, confirming the AR(MA)CH specifications in the stock return models.     

中国银行业规模经济和范围经济的实证研究——基于复合成本函数的分析

本文首次在国内利用复合成本函数估计我国国有商业银行和股份制商业银行1998——2003年的成本函数,并计算出各自的规模经济和范围经济。复合成本函数把投入价格的对数二次项和产出的二次项结合起来,具有优良的实证研究性质。实证研究结果表明:时间对我国银行业的规模经济和范围经济影响不显著;国有商业银行和股份制商业银行都存在着轻微的规模不经济和范围不经济,国有银行略好于股份制银行。我国商业银行的两种产出——存款和贷款不存在成本互补性。     

Testing for Vertical Fiscal Externalities

The purpose of this paper is to design a test of whether the vertical external effects associated with tax base sharing among local and regional governments have become internalized via the intergovernmental transfer system. Such tests are important in the sense that the income tax rates chosen by different levels of government will generally be correlated, even if the resource allocation is optimal from society's point of view. By using panel data for the Swedish local and regional public sectors, the results imply that an increase in the regional income tax rate induces the municipalities in the region to decrease their income tax rates. In addition, we are able to reject the null hypothesis that the vertical external effects have become internalized.     

旅游产品散论

目前学界对旅游产品的概念存在不少分歧,本文择取如下问题加以讨论:旅游产品是否包含媒介要素、是否是一种经历或体验、是否是商品、是否包含目的地出售的实物形态商品以及是否包含旅游资源.本文认为,媒介要素是旅游产品的必要组成部分,不能把旅游产品看作经历或体验,旅游产品是商品,旅游产品中不包含旅游地出售的旅游纪念品等实物形态商品,也不包括旅游资源.本文着重讨论了旅游资源与旅游产品的关系,提出旅游资源不是旅游产品或产品的一部分,而是、也仅仅是旅游产品生产要素中狭义的土地要素.     

赣江流域洪水峰量演变规律及联合分布研究

为研究赣江流域洪水特征,基于赣江流域外洲水文站1950-2019年共70年逐日流量资料,对年最大洪峰流量和1日洪量进行研究,通过Copula函数研究其洪水峰量联合分布情况。结果表明：赣江洪峰和洪量保持良好的一致性,均呈减少趋势;洪峰和洪量的最优分布均为gamma分布函数;Frank copula函数可以很好的拟合赣江洪峰和洪量的相关关系;洪水单变量重现期为5年一遇时,实际重现期为4.89～5.12年;当单变量重现期为100年一遇时,实际重现期为72.51～161.05年。     

拱坝体形优化研究进展

简要回顾了近年来拱坝体形优化理论研究的进展及成果,指出了今后在应用中将面对的困难及发展前景。     

无限长圆柱体的热弹性耦合问题

应用经典传热学理论,研究无限长圆柱体的热弹耦合问题。建立了经典传热学理论的控制方程,借助拉普拉斯积分变换及其数值反变换技术对问题进行了求解,得到了瞬态热冲击作用下无限长圆柱体中的温度、应力、位移的分布规律。从其分布图上可以看出,介质中呈现出热弹耦合效应。并且比较了传统热弹性理论与广义热弹性理论。