一个股价波动理论研究的新见解:基于异质情绪交易视角

传统金融理论中理性人假设并不能有效解释我国股票市场现象。国内学者基于行为金融理论,考虑投资者行为对股票市场的影响,但理论分析不足且鲜有聚焦于异质交易者情绪交易行为。因此本文从投资者情绪异质视角,把股票市场投资者划分为乐观交易者与悲观交易者,建立数学模型从理论上推导乐观情绪投资者、悲观情绪投资者与异质交易者结构对股票波动的交互影响机理。研究结果表明:乐观交易者占比较小的情况下,随着悲观情绪的缓和,乐观情绪对股价波动的效应是倒U形曲线;而随着乐观情绪的高涨,悲观情绪的缓和对股价波动同样呈倒U形。当乐观交易者占比很高时,乐观交易者情绪高涨与悲观情绪缓和均会助推股价波动。从异质交易者结构来看,乐观交易者占比对股价波动影响效应为正U形曲线,而更高水平的乐观情绪与更低水平的悲观情绪会提前其效应的反转。本文的研究结果较好地解释了牛熊市、虚假信息披露与宏观调控政策低效等事实的存在逻辑,为优化交易者结构,改善信息披露质量,进而防范股票市场系统性风险提供了理论依据。     

基于市场参与者行为假设的股票市场量价关系研究

基于市场参与者非理性行为假设,从供给需求分析出发,研究股票市场的量价关系.首先假设市场参与者具有"急于实现盈利"同时"不愿结算浮亏"的行为特征,通过供求分析,给出股票市场中的需求曲线与供给曲线,然后设定初始均衡,采用经济学中的比较静态分析方法,研究新信息到来时对初始均衡的影响,进而分析新信息的到来对成交量和价格的影响.结果发现,成交量和成交价格的变动正相关,成交量和成交价格变动的绝对值正相关.最后使用计量经济学方法,基于中国A股市场的个股日度数据进行了实证检验,实证结果支持了上述结论.     

投资者行为如何影响股票市场流动性?——基于投资者情绪、信息认知和卖空约束的分析

投资者交易行为是形成股票市场流动性的前提和基础,市场投资者情绪变化引起投资者产生有偏差的信息认知,通过卖空约束的市场行为选择影响市场流动性.论文首先通过理论推导得出影响市场流动性的三个命题,然后结合我国股票市场发展现状做出相应理论判断并对其进行实证检验.结果发现,在我国股票市场中,投资者情绪对市场流动性的影响是正向的,投资者情绪越高,市场流动性越强;我国股票市场中参与交易的投资者在面临新的消息面时更多的呈现出认知不足的特征.该特征的投资者随着认知程度的增加反而会降低市场流动性;与理论判断相反,我国股票市场中开展的融资融券业务进一步促进了投资者情绪对市场流动性的影响.最后就如何构建我国有效流动性的股票市场提出了四点政策建议.     

基于分位数Granger因果的网络情绪与股市收益关系研究

 行为金融学理论认为，股票市场的价格变动除受宏观基本因素影响外，还在很大程度上受众多个体投资者或噪音交易者行为左右。中国股票市场拥有庞大的个人投资者群体，且股民群体与网民群体之间具有高度耦合性，使用网络情绪等信息能够探索中国股市收益变动基本规律。        为揭示个体投资者行为对股市收益的影响，以个体投资者情绪为视角，以网络环境中个体投资者的情绪信息为切入点，检验投资者情绪与股市收益的关联关系，评估网络情绪信息价值。使用中文文本情感分析方法，从新浪微博文本中提取出网络情绪时间序列；分别运用均值Granger因果和分位数Granger因果检验方法，探讨网络情绪波动与股市收益之间是否存在因果关系；将股票市场发展阶段进行细致划分，研究不同市场阶段下网络情绪波动与股市收益之间的因果关系。        对沪深300指数收益进行实证研究，结果表明，尽管在均值框架下网络情绪波动与股市收益之间因果关系并不明显，但基于分位数Granger因果分析却发现两者在极端分位点区间处存在广泛且显著的因果关系。数据显示，在40个因果关系检验中，分位数Granger因果检验的因果关系发现了23个显著的因果关系，发现率为57.5%，远高于均值Granger因果检验的7.5%。此外，股市收益受到网络情绪波动影响的程度和方式在不同市场阶段下有所不同。        研究结果具有一定的理论意义和应用价值。在一些特定分位点区间网络情绪波动对股市收益存在显著因果关系影响，这为在特定条件下股市收益的可预测性提供了佐证。网络情绪能够预测股市收益的尾部(上尾或下尾)行为特征，可以为金融风险防范提供决策参考。研究结果为股票市场的定价、收益预测和波动率估计等相关研究提供了新的研究思路，也为网络情绪信息使用提供了新的方向。     

股票市场短期时间序列投机对经理投资行为的影响

公司投资行为受股票市场投机影响,投机性时间序列的实质是影响信息收集行为,股市短期时间序列投机者选择接收关于外生震荡不确定性的私人信息,博弈经理投资决策并对经理投资行为产生影响。本文基于信息结构研究股票市场短期时间序列投机对经理投资行为的影响,分析股票市场博弈均衡和经理有效均衡行为,阐明经理低效率投资决策行为的实质。     

计算实验金融、技术规则与时间序列收益可预测性

从受到广泛关注的简单技术规则视角,运用新兴的计算实验金融方法研究股票市场收益的时间序列可预测性,证明投资者非理性心理和行为是造成时间序列收益可预测性的原因.基于Swarm仿真平台和Objective C语言构建仿真模型TA-ASM,并进行多组不同参数下的计算实验,通过对模拟数据的统计分析发现,简单技术规则能获得超额收益,表明其在一定程度上具有时间序列收益可预测,该结果意味着收益时间序列存在可被简单技术规则侦测的部分.为确定潜在的影响因素的作用,研究进一步定性定量地对可能的各个内外生因素进行分析,最后得出投资者的非理性心理和行为作为一种系统风险被市场收益吸收从而导致时间序列收益可预测性的结论,该结论支持了行为金融理论关于个体的非理性存在于市场收益过程的假说.     

基于金融经济学的股票市场稳定研究

本文根据随机游走理论、有效性市场假说、市场的不确定性下的预期效用理论和前景理论、混沌理论、以及行为金融学等理论的演变,总结了前人对于影响股票市场价格变化的心理因素的金融经济学解释。并结合当前我国股票市场波动中存在的问题,提出了以投资者心理预期为调控对象的股票市场稳定建议。     

匹配追踪算法对上海股市价格行为的分析

股票市场价格变化因其复杂性,曾广泛被认为是一随机游走.本文应用匹配追踪算法,从一个称之为波形词典的函数库中自适应地提取出一系列与上证综指收益率序列最为匹配的时频原子;通过分析这些时频原子在时-频空间的能量分布以及与原序列信号的相关程度表明,上海股票市场价格变化不符合随机游走,并附带得出了一些其价格行为的有益结论.     

基于Markov和TAR模型的股市泡沫度量研究

股市泡沫的存在对投资者的行为有着巨大的影响,对于金融市场的稳健也至关重要。关于目前股票市场是否存在泡沫及泡沫大小程度的判断和分析对政策的制定、金融体制改革都具有很强的参考意义。本文通过分析上证指数及与股票市场密切相关的国民经济变量的时间序列,从马尔科夫模型和以门限自回归模型为基础的惯性门限自回归模型的基本原理出发,建立相应模型并进行实证研究,以量化的方法对我国的股票市场泡沫进行度量研究,并提出度量和预防股市价格泡沫的政策建议。     

对中国证券机构投资者预测能力的实证分析

对股票价格走势特征的研究是证券投资理论永恒不变的主题，从传统金融理论到行为金融理论．无论从何种角度进行研究和分析，都是围绕这一主题展开的。本文将运用近几年最有影响的行为金融理论．通过实证分析检验中国机构投资者对股票走势的预测能力。以BSI指标代表投资者预期．研究其与中国股票市场收益情况的相关性，通过历史数据的回归分析加以判断，得出了股票市场短期走势不可预测的结论。     

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.