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151.
Research Summary: Research exploring investor reactions to sustainability has substantial empirical limitations, which we address with a large‐scale longitudinal financial event study of the first global sustainability index, DJSI World. We examine investor reactions to firms from 27 countries over 17 years that are added, deleted, or continue on the index. We find that once relevant controls and comparisons to observationally equivalent firms beyond the index are included, DJSI events have only limited significance and/or materiality. Nonetheless, investors' valuation of sustainability around the world has evolved over time, involving diminishing reactions to U.S. firms and increasing benefits, particularly of continuation on the index, over time. The study highlights the importance of careful analysis and longitudinal global samples in making inferences about the financial effects of social performance. Managerial Summary: The debate about how investors perceive corporate social responsibility (CSR) predates Milton Friedman's famous statement that the only social responsibility of business is to increase profits. Although extensive research has studied whether sustainability contributes to financial performance, we have yet to understand whether investors believe it pays off. This financial event study of reactions to the addition, continuation, and deletion from DJSI World, the first global sustainability index, shows that investors care little about DJSI announcements. Nonetheless, there is some evidence that global assessments of sustainability are converging and that investors may increasingly be valuing continuation on the DJSI, suggesting that firms may gain at least limited benefits from reliable sustainability activities.  相似文献   
152.
旅行费用法若干问题研究   总被引:5,自引:0,他引:5  
20世纪90年代,环境学领域研究者开始使用旅行费用法研究生态保护区及世界遗产类旅游景点的价值。环境科学的研究背景使得目前已有的成果缺少对于旅游学范畴相关变量的考虑。文章基于旅游学科,对于旅行费用法使用过程中模型及函数形式的选择、旅行时间的价值度量、多目的地旅行、替代效应及拥挤效应等问题进行了综述和阐释,期待多学科的合作研究使未来的旅游景点价值评估更加客观。  相似文献   
153.
ARIMA计量技术下河南省农民增收的预测模型研究   总被引:1,自引:0,他引:1  
杨茂 《经济经纬》2007,(4):110-112
笔者根据河南省1978年~2005年的农民人均纯收入统计数据,将这些数据进行平稳化、零均值化处理,并利用时间序列的自相关函数,偏自相关函数的性质,确认数据所适合的模型.通过对样本数据所做的回归拟合模型定量分析,从而为河南省"十一·五"规划提供量化指标依据.  相似文献   
154.
运用灰色关联分析方法确定科技投入相对科技产出的滞后期,用滞后影响系数法计算出修正的科技产出值,在视窗分析方法中引入考虑科技投入产出滞后效应的Super-SBM模型,评价9个先进制造业科技投入产出的效率值。视窗分析方法能够衡量同一个决策单元在不同时期的相对效率情况,Super-SBM模型更充分地考虑科技投入产出的松弛性问题,能进一步区分有效的决策单元,综合这两种方法使得本文的评价过程更符合实际。  相似文献   
155.
陈翠燕 《价值工程》2006,25(8):102-104
软件项目的风险及其管理一直没有得到太多的重视,但它对软件项目的成功起着至关重要的作用。本文概述了软件项目的风险;在现有软件项目风险管理理论的基础上,提出了软件项目风险管理的三维理论框架;并对时间维、知识维和逻辑维进行综合探讨和分析,明确了这三维之间的关系;最后结合我国当前的社会环境和技术环境,提出了几项建议。  相似文献   
156.
利用相对价格冲击函数的Box-Cox变换和存在比例交易费用的线性函数,研究了非瓦尔拉斯均衡金融市场上风险资产的价格变现策略,当资产价格变化服从几何布朗运动时,资产变现时间内生情形下投资者最优变现策略问题可以转化为具有随机跳出时间的随机最优控制,通过对带有广义狄利克雷边界条件的贝尔曼方程的粘性求解,可以实现最优变现策略。  相似文献   
157.
近几年来,随着我国研究生招生规模的急剧扩大,研究生的增加与资源的相对短缺,已成为制约高校研究生教育进一步发展的瓶颈之一。本文分析了当前高校研究生自身特点,找出了高校研究生管理中存在的一些问题并进行了详细的分析,提出了加强高校研究生管理的一些建设性意见。  相似文献   
158.
The scarce previous literature indicates that the customer toilet facilities influence shopping value and should be a concern for retailers. However, customer toilets are often inadequately capitalised in retail stores. This study aims to provide a scientifically robust argument about the critical role of customer toilets in retail stores. The explanatory survey data (n=655) from a Finnish out-of-town department store is examined to explore (1) the importance that consumers place on the customer toilets and (2) the effect of toilet usage on actual shopping behaviour. The results support the assumptions of previous literature by suggesting that customer toilets are considered as an important store attribute and, more importantly, the use of toilets is associated with prolonged in-store time which, in turn, increases spending. The findings offer both academic and managerial contribution and encourage academics and practitioners to regard customer toilets as more than mere an unwanted property expense and discover their full marketing potential.  相似文献   
159.
Abstract

Background:

To evaluate the cost burden of patients with advanced Parkinson’s disease (PD) according to the waking hours per day spent in OFF state. An analysis of resource use comprising medical services, professional care and informal care data from an observational, cross-sectional study was conducted.

Methods:

A total of 60 physicians comprising 40 neurologists and 20 geriatricians across the UK participating in the Adelphi PD Disease Specific Programme took part. There were 302 PD patients at H&Y stages 3–5. Patients were characterised according to the percentage of time per day spent in OFF state (<25%, 26–50%, 51–75%, >75%).

Results:

Average 12-monthly total costs increased according to the time spent in OFF state from £25,630 in patients spending less than 25% of their waking hours in OFF to £62,147 for patients spending more than 75% of their time in OFF. Overall, 7% of costs were attributed to direct medical care, while 93% were split between direct non-medical professional care (50%) and indirect informal care (43%).

Limitations:

Low patient numbers in the more advanced disease stages of PD led to very little or no data to directly inform some of the severe health states of the analysis. Data gaps were filled in with data derived from a regression analysis which may affect the robustness of the analysis.

Conclusion:

This study illustrates the increasing costs of advancing PD, in particular related to the time spent in OFF state, and identifies that the foremost cost burden is associated with the care needs of the patient rather than medical services.  相似文献   
160.
In this paper, we consider a flowshop scheduling problem with sequence-dependent setup times and a bicriteria objective to minimize the work-in-process inventory for the producer and to maximize the customers' service level. The use of a bicriteria objective is motivated by the fact that successful companies in today's environment not only try to minimize their own cost but also try to fulfill their customers' need. Two main approaches, permutation and non-permutation schedules, are considered in finding the optimal schedule for a flowshop. In permutation schedules the sequence of jobs remains the same on all machines whereas in non-permutation schedule, jobs can have different sequence on different machines. A linear mathematical model for solving the non-permutation flowshop is developed to comply with all of the operational constraints commonly encountered in the industry, including dynamic machine availabilities, dynamic job releases, and the possibility of jobs skipping one or more machines, should their operational requirements deem that it was necessary. As the model is shown to be NP-hard, a metasearch heuristic, employing a newly developed concept known as the Tabu search with embedded progressive perturbation (TSEPP) is developed to solve, in particular, industry-size problems efficiently. The effectiveness and efficiency of the search algorithm are assessed by comparing the search algorithmic solutions with that of the optimal solutions obtained from CPLEX in solvable small problem instances.  相似文献   
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