中国地级以上城市基础设施评价研究

考察了城市基础设施的内涵,建立了由3个层级、5个维度和22个指标构成的城市基础设施评价体系,并采用极差标准化、均方差决策、加权平均和标准分等方法,对中国2007年287个地级及以上城市的基础设施建设水平从发展排序、等级划分、空间分异和统计分布等方面进行了全面、系统的评价研究。结果显示:城市基础设施具有和经济发展相似的自东向西递减的地带性特征;大部分城市的基础设施发展不均衡,存在短板;全国地级以上城市基础设施的总体水平呈正态分布,环境设施呈尖峰左偏分布,交通设施呈尖峰右偏分布,供排水设施属于平顶正态分布,能源设施分布曲线波动较大,邮电设施分布严重右偏。本研究为城市基础设施建设提供政策思路和科学依据。     

Free Cash Flow, Golden Parachutes, and the Discipline of Takeover Activity

We conjecture that golden parachutes are initiated when the agency cost of free cash flow is most severe. We examine the relation between golden parachutes and investment levels in firms that have been successfully acquired. Our results support these three conclusions. First, target firms overinvest prior to an acquisition when golden parachutes are present. Second, the acquirers of targets with golden parachutes reduce investment subsequent to the takeover. Third, the reversal in capital investment by the combined firm is correlated with the magnitude of the target's pre-acquisition overinvestment. The latter findings indicate the takeover acts as a disciplining mechanism with the acquirer reversing the target overinvestment subsequent to the acquisition     

A novel approach to portfolio selection using news volume and sentiment

In this study, we develop a novel approach to portfolio diversification by integrating information on news volume and sentiment with the k-nearest neighbors (kNN) algorithm. Our empirical analysis indicates that high news volume contributes to portfolio risk, whereas news sentiment contributes to portfolio return. Based on these findings, we propose a kNN algorithm for portfolio selection. Our in-sample and out-of-sample tests suggest that the proposed kNN portfolio selection approach outperforms the benchmark index portfolio. Overall, we show that incorporating news volume and sentiment into portfolio selection can enhance portfolio performance by improving returns and reducing risk.     

黄金周假日旅游存在的问题及对策研究综述

近年来,黄金周假日旅游蓬勃发展,满足了国民日益增长的旅游需求,促进了旅游业及社会经济的发展;但同时,黄金周假日旅游中也暴露出来很多问题,引起了各方面的强烈关注,引发了各界特别是旅游学界对黄金周假日旅游及黄金周制度的研究和探讨.本文试图对近年来有关黄金周假日旅游中存在的问题、成因及解决问题的对策的研究做一回顾和总结.     

论孔子中庸思想的公正意蕴

任何一种社会秩序都奠基于一定的公正观念之上,从一定意义上讲,秩序乃是公正的外化。在一个具有漫长文明史的社会中,人们不可能不对如何分配他们各自的社会政治地位这样一个基本问题做出回答。孔子的中庸思想即内涵着丰富的公正意蕴——“中”:公正的标准;“礼”:公正的规范原则;“和”:公正的理想目标。     

中国近代工业化发展的三次浪潮及启示(1895-1937年)

中国的近代工业化经历了三次浪潮并取得了骄人的成果。通过对三次工业化浪潮的原因分析,得出以下结论:战乱和社会的动荡并不必然导致经济的衰退,市场机制具有自我修复的特性;政府在经济发展的初期,越位比缺位的危害更严重。     

A Flexible Neuro‐Fuzzy Approach for Improvement of Seasonal Housing Price Estimation in Uncertain and Non‐Linear Environments

Changes in housing price affect both individuals and government since they have substantial influence on the socio‐economic conditions. Valuations of housing are necessary in order to assess the benefits and liabilities in housing sector. This study presents a flexible meta‐modelling approach for improvement of housing price estimation in ambiguous and complex environments. It is composed of artificial neural network (ANN) and fuzzy linear regression (FLR). Seven FLR models are considered to cover latest approaches and viewpoints. Also, ANN is applied to data sets. The preferred FLR model is selected via mean absolute percentage of error (MAPE) for further considerations, and then the preferred FLR model and the best structure of ANN are applied to the data set. Finally, the preferred model is selected based on MAPE. The intelligent approach of this study is applied for estimation and forecasting housing price in Iran. The housing price in Iran mainly is based on eight economic indices including currency, oil income, general index, house service pricing index, rate of informal market, gross domestic production in basic price, added value of oil group and construction materials price. FLR is identified as the preferred model with lowest MAPE for housing price forecasting in Iran. This shows that the housing market of Iran is associated with severe environmental fuzziness and ambiguity. This is the first study that introduces a flexible neuro‐fuzzy approach for improved estimation and forecasting of housing price in noisy, complex and uncertain environments.     

成渝经济区对外开放战略的新思维

成渝经济区对外开放的战略构想要有新思维,要从“西部与世界相连”、两个前沿地带、国家新的增长极三个视角审视成渝经济区对外开放战略,要从产业振兴、川渝合作、西部高科技金三角崛起三个途径夯实成渝经济区对外开放基础,要从毗邻区域合作、泛区域合作、国际区域合作三个维度拓展成渝经济区对外开放空间。     

RISK MEASURES: RATIONALITY AND DIVERSIFICATION

When there is uncertainty about interest rates (typically due to either illiquidity or defaultability of zero coupon bonds) the cash‐additivity assumption on risk measures becomes problematic. When this assumption is weakened, to cash‐subadditivity for example, the equivalence between convexity and the diversification principle no longer holds. In fact, this principle only implies (and it is implied by) quasiconvexity. For this reason, in this paper quasiconvex risk measures are studied. We provide a dual characterization of quasiconvex cash‐subadditive risk measures and we establish necessary and sufficient conditions for their law invariance. As a byproduct, we obtain an alternative characterization of the actuarial mean value premium principle.     

英语教师角色转变中的利器——配对均值假设检验

假设检验是数理统计学研究的一个重要部分,是研究比较不可或缺的部分,是教师由教学型向教研型转变、实现教学研究两条腿走路的法宝,是展示成果有力的分析工具。从英语学科出发,实例探讨假设检验在其中的应用,具体展示其分析论证的强大作用,以期为英语教师成长、实现教学向教研型转变提供范例。