证券投资基金业绩与持续性评价的实证研究--基于DEA模型与R/S模型的评价

科学合理的基金评价体系有助于提高基金运作水平、促进基金业可持续发展,而传统的投资基金业绩评估方法存在着诸多问题,如Treynor业绩指数法、Sharpe业绩指数法以及Jensen业绩指数法等.为了克服上述评价指数存在的诸多问题,在国内外学者对基金业绩评价研究的基础上,运用数据包络模型(DEA)和R/S模型对基金的相对业绩及可持续性进行了实证研究,为基金的评价和监管提供科学的依据.     

投资基金绩效评价的Sharpe 指数与 衰减度实证分析

投资基金绩效评价的Sharpe 指数与 衰减度实证分析     

中国投资基金波动择时能力的实证研究

投资基金的择时能力是基金绩效评价的核心内容。本文通过引入收益择时因子改进了Busse的波动择时模型,并以此为工具从波动时变性的角度对我国证券投资基金的择时能力进行了实证研究。实证结果表明,不仅中国证券投资基金具有较为显著的波动择时能力,开放式基金的波动择时能力强于封闭式基金;而且改进的波动择时模型优于Busse波动择时模型。     

我国证券投资基金业绩分析

从综合业绩度量、证券选择水平和市场时机选择水平三个方面分析了我国证券投资基金业绩.研究表明,我国证券投资基金业绩普遍高于市场平均收益,大部分基金具有较强时机选择能力;但同时分析也表明,相当一部分基金选择股票能力需要提高.     

基于VaR的Sharpe指标在基金业绩评价中的应用

针对标准差衡量风险中的缺陷，本文考虑下方风险和收益波动的时变性，对计算Shapre值时的风险测度进行了调整。实证部分，应用传统的Sharpe比率、基于VaR的Sharpe比例和基于条件VaR的条件Sharpe值对中国证券市场上运作满3年的33只封闭式基金在2001—2003年间的业绩进行了检验，分析了基金控制风险和实现收益水平上的差异。     

证券投资基金业绩的持续性研究

本文选取1999年底前上市的20家证券投资基金的净资产值数据为样本,运用独立性检验、自相关系数检验等方法,实证研究了我国基金业绩的持续性问题,并对研究的结果进行了切实、中肯的分析,对进一步研究证券投资基金业绩的持续性问题具有一定的指导意义.     

中国证券投资基金市场波动特征实证研究

根据不同类型的ARCH类模型的特点及其所刻画的市场波动特征,本文对中国证券投资基金市场波动的聚集性进行检验,分别运用EGARCH和TGARCH模型对证券投资基金波动的非对称性和杠杆效应进行实证研究,运用EGARCH-M模型对证券投资基金波动的风险溢价效应进行实证分析,运用改进的EGARCH模型对证券投资基金波动与信息的关系进行实证研究,并对实证结果进行分析.     

中国证券投资基金业绩持续性研究综述

近年来,中国证券投资基金发展势头迅猛,基金规模和数量迅速扩张.在这样一个时机进行基金业绩持续性研究是具有重大的理论和现实意义.本文介绍了国内关于基金业绩持续性的研究文献,并对研究成果进行总结,最后给出了进一步的研究方向.     

中国证券投资基金绩效持续效应研究

过去绩效表现好的证券投资基金在未来绩效表现是否也会好?也就是说:证券投资基金绩效是否持续?这个问题引起了理论界和实务界共同的关注.理论界关注这个问题是因为有效市场假说预言通过研究现有信息无法获得超额收益,这可以推论出证券投资基金无法持续创造好于大盘的收益率.实务界关注这个问题是因为有大量的投资者倾向于购买在过去绩效表现比较好的基金,卖出过去绩效比较差的基金.这种投资行为是否理性?如果基金绩效持续,那么这种投资行为就是理性的.本文针对中国封闭式证券投资基金2001年1月1日～2004年5月31日期间的数据进行的研究表明:不能认为中国证券投资基金普遍具有绩效持续效应,但是中国证券投资基金在大约1/3左右的子区间表现出了绩效持续效应.     

证券投资基金系统的非线性实证研究

选取沪、深证券交易所证券投资基金指数对数收益率为研究对象,分别采用分形、R/S统计检验、关联维检验、李雅普诺夫指数检验等方法实证得知中国证券投资基金系统具有分形、自相关性、混沌、李雅普诺夫指数大于零等非线性特征。由于证券投资基金系统具有混沌性,那么证券投资基金制度发展必然对初始条件具有敏感的依赖性,因此可以采用市场化的制度创新手段,培养证券投资基金系统的混沌吸引子,促使证券投资基金系统向着更高层次的有序态演化。     

Introduction to Special Section on Sensitivity Analysis and Summary of NCSU/USDA Workshop on Sensitivity Analysis

This guest editorial is a summary of the NCSU/USDA Workshop on Sensitivity Analysis held June 11–12, 2001 at North Carolina State University and sponsored by the U.S. Department of Agriculture's Office of Risk Assessment and Cost Benefit Analysis. The objective of the workshop was to learn across disciplines in identifying, evaluating, and recommending sensitivity analysis methods and practices for application to food‐safety process risk models. The workshop included presentations regarding the Hazard Assessment and Critical Control Points (HACCP) framework used in food‐safety risk assessment, a survey of sensitivity analysis methods, invited white papers on sensitivity analysis, and invited case studies regarding risk assessment of microbial pathogens in food. Based on the sharing of interdisciplinary information represented by the presentations, the workshop participants, divided into breakout sessions, responded to three trigger questions: What are the key criteria for sensitivity analysis methods applied to food‐safety risk assessment? What sensitivity analysis methods are most promising for application to food safety and risk assessment? and What are the key needs for implementation and demonstration of such methods? The workshop produced agreement regarding key criteria for sensitivity analysis methods and the need to use two or more methods to try to obtain robust insights. Recommendations were made regarding a guideline document to assist practitioners in selecting, applying, interpreting, and reporting the results of sensitivity analysis.     

Distinguishing traumatic, vicarious and routine operational stressor exposure and attendant adverse consequences in a sample of police officers

Problems in studying occupational stress within the police service are identified and the paucity of work on operational duties as potential stressors are discussed. The present study reports the results of a factor analysis of operational stressors (N = 601 serving British police officers) that revealed three factors: exposure to death and disaster; violence and injury; sexual crime. These were demonstrated to be reliable scales and were included in logistic regression models together with a range of demographic and psychological variables. Models were applied to men and women separately, which showed there to be different predictors of the likelihood of suffering distress (measured by the General Health Questionnaire, GHQ) in terms of the officer's gender and operational role. Overall the model for women officers was better at predicting psychological distress than that for men. These findings are related to aspects of the police occupational culture. Further discussion is offered that conceptualizes police operational stressors as traumatic, routine and vicarious. Finally, some implications are drawn for the provision of stress intervention in the light of this differentiation.     

Power,authority and legitimacy

Management, human resources, organization, control, leadership, etc., all seem to be just so many euphemisms for power, and this suggests a discourse of management and organization that calls things by their proper name. This paper on the contrary stresses the need to resolve the concept of ‘power’ itself into more differentiated notions, and proposes that clarification may be derived from distinctions once explicit in the vocabulary of Classical antiquity, but lost in modern European languages. It argues that nothing but confusion in thinking about organizations, management and legitimation can result from the failure to recognize that the phenomena this vocabulary identifies and distinguishes are irreducibly different.     

Criteria for selecting a production control philosophy

Logistic objectives constitute a compromise between having short leadtimes and a low volume of work in progress on the one hand and a high resource loading and due date obligation on the other. Miscellaneous production planning approaches offered today provide different combinations of logistic objectives for satisfying a manufacturing strategy. To combine the strength of the various approaches into a unified system, a new approach based on a dynamic and distributed production planning methodology is proposed. To customize the approach, various analyses and specifications have to be made and for that reason some important characteristics and criteria for analysing production control philosophies will be given.     

Employees' perceptions of organizational restructuring: the role of social support

Organizational change and restructuring is often perceived as leading to increased occupational stress, impacting negatively on the psychological well-being of employees. This pragmatic study investigates the role of social support and dispositional affect as moderators of role stress post-restructuring for employees in a public utility company. A total of 176 employees, including 37 managers, 60 graded staff and 78 industrial staff completed a self-report questionnaire, approximately 1 year postrestructuring, retrospectively assessing role conflict, ambiguity, overload and positive and negative feedback pre- and post-restructuring. Results suggested that overall role stress increased for managers/ senior officers and graded staff, but not for industrial staff. Social support was linked with lower role stress, more positive feedback and less negative feedback at post-restructuring. For certain role stressors this impact was moderated by dispositional affect, but the effect was not consistent across occupational groups. Positive affect enhanced the effect of manager support in reducing role conflict for graded staff, and the effect of co-worker support in increasing positive feedback and reducing negative feedback for industrial staff. Findings suggest that managers should pay particular attention to support and feedback for employees during periods of chronic occupational stress following organizational restructuring.     

The Danish psychosocial work environment and symptoms of stress: the main, mediating and moderating role of sense of coherence

The aim of this cross-sectional study was to explore the main, mediating and moderating role of sense of coherence (SOC) on stress symptoms and on the association between perceived psychosocial work environment and stress symptoms. The sample includes 2053 Danish employees from 52 workplaces. Hierarchical regression models were applied for each measure of stress. The results strongly supported the presence of a main effect for SOC. People with high levels of SOC experienced fewer stress symptoms. A mediating effect of SOC was also supported. Thus, SOC in part explained the association between work environment and stress symptoms. In addition, some support for a moderating effect of SOC was found, suggesting that people with higher SOC coped more efficiently with work environmental strain that people with lower SOC. Taken together the regression models explained 11-32% of the variance in stress symptoms. The results suggest that measures of individual factors such as SOC should be included in analyses of the effects of work environmental factors on stress and well-being.     

Control at work: a generalized resource factor for the prevention of musculoskeletal symptoms?

During the last two decades two potent groups of predictors for work-related musculoskeletal problems have been identified: physical work load and poor psychosocial working conditions. However, little is known about their combined effects. In this study the buffering effect of control at work with respect to the negative effects of psychological demands and physical work load on musculoskeletal problems is examined. All study variables were sampled from 431 people working in geriatric nursing homes in Germany by means of questionnaires. Main effects and interactions were tested with multiple regression analysis. The results showed that control buffered the effects of high psychological demands, but not of high physical work load; the buffering effect of control was observed only when physical work load was low. The combined effects of demands and physical work load were over-additive. Thus, the power of different predictors for musculoskeletal symptoms depended on the level of other predictors. This suggests that the efficiency of certain strategies for the prevention of musculoskeletal problems is likely to depend on the level of risk factors, with different strategies being appropriate for different levels of risk.     

The social construction of the meaning of acute stressors: a qualitative study of the personal accounts of police officers using a stress counselling service

The police profession is one in which acute stressors are encountered more frequently than in other occupations. Using the personal accounts of 35 police officers attending an in-house stress counselling clinic, the aim of the present study was to provide a qualitative examination of how the institutional context of policing influenced the ways in which acute stressors signified to individual police officers experiencing felt distress. Using the framework of Rational Emotive Behaviour Therapy as an analytical tool, it is argued that beliefs contributing to the experience of felt distress are related to the way in which policing as both an identity and an activity is constructed through the police organizational culture. Not only do these constructions influence the ways in which officers perceive themselves and their environments, but they also operate at the collective level to 'normalize' some emotional responses and to 'pathologize' others which, it is argued, could impact upon the outcomes of interventions such as stress counselling.     

The moderating role of social support in Karasek's job strain model

This paper examines whether social support is a boundary-determining criterion in the job strain model of Karasek (1979). The particular focus is the extent to which different sources of social support, work overload and task control influence job satisfaction, depersonalization and supervisor assessments of work performance. Hypotheses are tested using prospective survey data from 80 clerical staff in a university setting. Results revealed 3-way interactions among levels of support (supervisor, co-worker, non-work), perceived task control and work overload on levels of work performance and employee adjustment (self-report). After controlling for levels of negative affect in all analyses, there was evidence that high levels of supervisor support mitigated against the negative effects of high strain jobs on levels of job satisfaction and reduced reported levels of depersonalization. Moreover, high levels of non-work support and co-worker support also mitigated against the negative effects of high strain jobs on levels of work performance. The results are discussed in terms of the importance of social support networks both at, and beyond, the work context.     

Job insecurity, coping resources and personality dispositions in occupational strain

This paper presents research on the relationships between the work-related stressor of perceived job insecurity and various indicators of occupational strain, taking into account employees' personality dispositions (trait negative and positive affectivity) and coping resources. Respondents were 222 Australian public servants surveyed during organizational restructuring that involved downsizing and threat to job certainty. The research was formulated within an adaptation of Osipow, Doty, and Spokane's (1985) framework of stress-strain-coping that included the possible direct as well as moderating effects of personality dispositions in reporting occupational strain (Parkes, 1990). Findings from hierarchical regression analyses indicate consistent significant independent effects of personality dispositions, coping resources and perceived job insecurity on various indicators of strain. There was also support for the moderating roles of negative affectivity and self-care in the relation between perceived job insecurity and physical strain. Implications for the role of dispositional factors, especially negative affectivity, and the utility of various coping resources in accounting for occupational strain in times of threatened job security are discussed.