硕士研究生综合素质培养的现存问题与改进研究

我国园林硕士研究生综合素质培养教育中,存在着思维能力、专业实践能力、协调能力及耐挫折能力较差,基本功不扎实,缺乏社会责任感以及科技创新能力薄弱等现实问题,借鉴国外先进教育理念,提出完善培养模式,分步分项地促进研究生综合素质和能力,严把入学和毕业质量关,提高导师队伍素质等改进建议,以期对今后我国硕士研究生的教育工作有所启发和借鉴。     

优化产能空间布局疏解京津冀雾霾污染

雾霾污染关乎人民群众的身心健康,全面建成小康社会的伟大目标不能在满眼雾霾中实现。京津冀雾霾问题的症结在于三高产业(高能耗、高排放、高污染)在人口密集地区过度集中,产生的巨量排放在不利气象和地理条件下与城市交通、采暖、扬尘等排放因素叠加形成严重的雾霾污染,因此有必要结合国家区域发展战略,优化高耗能产业的空间布局,协调好产业与城市的空间关系,尤其要处理好高耗能产业与高密度城市群的空间布局关系,抓紧制定三高产业的空间布局规划,通过实施三高产业空间优化布局战略打破三高产业在人口稠密地区的过度集中,实现对京津冀地区雾霾污染的有效治理。     

Mitigating Inventory Overstocking: Optimal Order‐up‐to Level to Achieve a Target Fill Rate over a Finite Horizon

Service level agreements (SLAs) are widely adopted performance‐based contracts in operations management practice, and fill rate is the most common performance metric among all the measurements in SLAs. Traditional procedures characterizing the order‐up‐to level satisfying a specified fill rate implicitly assume an infinite performance review horizon. However, in practice, inventory managers are liable to maintain and report fill rates over a finite performance review horizon. This horizon discrepancy leads to deviation between the target fill rate and actual achieved fill rate. In this study, we first examine the behavior of the fill rate distribution over a finite horizon with positive lead time. We analytically prove that the expected fill rate assuming an infinite performance review horizon exceeds the expected fill rate assuming a finite performance review horizon, implying that there exists some inventory “waste” (i.e., overstocking) when the traditional procedure is used. Based on this observation and the complexity of the problem, we propose a simulation‐based algorithm to reduce excess inventory while maintaining the contractual target fill rate. When the lead time is significant relative to the length of the contract horizon, we show that the improvement in the inventory system can be over 5%. Further, we extend our basic setting to incorporate the penalty for failing to meet a target, and show how one can solve large‐scale problems via stochastic approximation. The primary managerial implication of our study is that ignoring the performance review horizon in an SLA will cause overstocking, especially when the lead time is large.     

“追名”还是“逐利”：独立董事履职动机之探究

 经营权与控制权分离引发的代理问题是催生独立董事这一群体的制度根源。引入独立董事制度,维护公司整体利益,尤其是关注中小股东的合法权益不受损害,是监管机构改善公司治理结构的重要举措。独立董事在本质上也是剩余索取者的代理人,与股东之间同样存在代理问题。如何构建独立董事激励机制,使其与中小股东建立有效受托责任关系,是监管部门和实务界面临的一大难题。        以2002年至2015年沪、深两市A股主板上市公司为样本,使用手工配对法、Logit回归和OLS回归,采用进一步分析和一系列稳健性检验,从个人特征、公司特征和制度环境3个层面考察零薪酬独立董事的影响因素,并从“追名”和“逐利”两个角度对独立董事履职动机进行探讨。        研究结果表明,从个人特征看,零薪酬更可能出现在独立性较强的董事中;从公司特征看,零薪酬更可能出现在违规风险较低的公司;从制度环境看,零薪酬更可能出现在市场化程度较高的地区。零薪酬独立董事在出席董事会时也更加勤勉,以上结论与“追名”动机逻辑一致。进一步研究发现,会计背景的零薪酬独立董事能进一步甄别出财务风险更高的公司;由于存在自选择,零薪酬独立董事任职公司的治理水平更高,其并未出具更多的否定意见。        研究结果说明经济和声誉两种激励方式在不同独立董事个体间发挥的作用差异较大。一方面,为独立董事零薪酬现象提供了合理解释,说明上市公司应当根据自身所处的制度环境、风险水平以及每位独立董事的具体特征等设定差异化的薪酬水平;另一方面,也对监管部门完善独立董事激励机制、培育独立董事人才市场具有现实的指导意义。     

基于线性插值的贝叶斯Lasso分位数回归及应用

在贝叶斯Lasso分位数回归中,样本似然函数的计算和后验分布的抽样通常难以处理.针对这一问题,文章采用一种基于线性插值的似然函数计算方法,并结合拉普拉斯先验分布,设计出一种新的对后验分布进行抽样的算法.数值模拟结果表明了该方法具有较好的适应性和参数估计准确性.     

基于蒙特卡洛方法的金融市场风险VaR的算法分析

为解决蒙特卡洛(Monte Carlo)方法在计算风险价值(Value at Risk,VaR)方面的缺陷,文章首先引入GARCH模型来刻画金融数据的波动聚集性,再引入马尔科夫链蒙特卡洛(Markov Chain Monte Carlo,MCMC)方法,来克服GARCH模型参数估计约束条件带来的估计误差.通过对上证50指数的实证分析表明,引入MCMC方法可以提高模型的估计精确度.     

马克思主义城乡关系原理面临的现实挑战及理论思考

城乡关系问题一直是社会各界广泛关注的问题,对这一问题的研究与讨论非常多,其中既有理论研究,也有实践论证。试图以马克思主义城乡关系原理为视角,考察其在现实应用与发展进程中面临的挑战,并分析其背后的深层次原因,进而通过理论思考提出实践对策。     

Better Government,Happier Residents? Quality of Government and Life Satisfaction in China

Social Indicators Research - How quality of government affects residents’ life satisfaction is a seldom discussed subject, especially in a non-democratic context. This research aims to...     

Matching a correlation coefficient by a Gaussian copula

A Gaussian copula is widely used to define correlated random variables. To obtain a prescribed Pearson correlation coefficient of ρ_x between two random variables with given marginal distributions, the correlation coefficient ρ_z between two standard normal variables in the copula must take a specific value which satisfies an integral equation that links ρ_x to ρ_z. In a few cases, this equation has an explicit solution, but in other cases it must be solved numerically. This paper attempts to address this issue. If two continuous random variables are involved, the marginal transformation is approximated by a weighted sum of Hermite polynomials; via Mehler’s formula, a polynomial of ρ_z is derived to approximate the function relationship between ρ_x and ρ_z. If a discrete variable is involved, the marginal transformation is decomposed into piecewise continuous ones, and ρ_x is expressed as a polynomial of ρ_z by Taylor expansion. For a given ρ_x, ρ_z can be efficiently determined by solving a polynomial equation.     

An Empirical Model for Managing Quality in the Electronics Industry

Much of the empirical research in the past two decades has suggested that quality management (QM) is context dependent. This research develops an empirical QM model in a technology‐based sector—electronics manufacturing. Based on quantitative and qualitative investigations of 225 electronics firms in Hong Kong and the Pearl River Delta (PRD) region of China, a path analytic model is developed. The empirical model shows that a typical quality management system (QMS) in the electronics industry is composed of four major modules, namely leadership, cultural elements, operational support systems, and process management. These modules create a series of chain effects on organizational performance, rather than acting as parallel elements with an equal impact. By quantifying their effects on organizational performance and comparing the model to others in the literature, we identify those QM constructs that are context dependent. In electronics manufacturing, process management and customer focus are more important than other elements (e.g., cultural factors) for garnering business results. This study contributes to contingency theory and research by identifying the key constructs and their relationships in a competitive, volatile, and technology‐based industry with complex supply networks.