特质风险可以用来定价吗？*--来自中国股市的证据

本文基于一般均衡分析框架从理论上推导出股票特质波动率与横截面收益之间的相关关系,并借助中国股市的数据进行了验证。研究结果表明：股票特质波动率每上升1个百分点,横截面收益要相应补偿3-5个百分点,且不受所有制、行业因素或者股票错误定价的影响。同时,本文从有限套利理论的角度出发,解释了特质波动率与股票横截面收益之间呈现正相关关系的原因。     

市场摩擦对特质风险溢价的影响效应——基于A股主板市场的实证分析

与国外发达市场相比,我国A股主板市场的市场摩擦因素对市场微观结构和资产定价的影响更大。在防范和化解系统性风险的过程中,进一步分析市场摩擦如何作用于特质风险定价效应的问题具有重要的理论和现实意义。本文通过采用多维市场摩擦指标来代理信息不对称、交易成本、买卖限制、卖空限制、风险对冲和外部冲击,检验中国股市特质风险和预期收益率的关系,并判断出市场摩擦因素间的差异性影响机制。回归发现,市场摩擦和特质风险因子(特质波动率和特质偏度)都具有定价效应。各维度市场摩擦因素降低了股票流动性,进而增强了特质波动率的负向定价效应,部分解释了“特质波动率之谜”,但市场摩擦对特质偏度因子溢价的影响较为微弱。同时,基于特质波动率和特质偏度因子的投资策略能够产生超越CAPM、三因子和五因子模型的绝对收益,并印证了市场摩擦对特质风险因子绝对收益的影响作用。     

我国上市公司定向增发对股价特质性波动的影响研究

本文基于修正后的Fama-French三因子模型,以2016年全年沪深股市定向增发的上市公司作为样本,运用EVIEW7.2、SPSS19等统计软件实证分析我国上市公司定向增发对股价特质性波动的影响。通过对实证结果的分析,发现短期来看我国定向增发对股价特质性波动率有明显抑制作用,并且发现信息透明度和投资者情绪对股价特质性波动率的影响是显著的。基于实证结果的分析也为企业经营者和投资者提出相关建议。     

特质风险与市场收益动态关系的实证研究

本文使用流通市值加权的股票平均波动率作为股票市场未分散特质风险的间接衡量指标,对A股市场特质风险与市场预期收益之间的动态关系进行研究。有别于国内已有研究,本文使用流通市值加权股票平均波动率的自回归残差项作为回归模型的解释变量,避免了解释变量高度持续性特征给回归结果造成的不利影响,发现A股市场未分散的特质风险对预期市场超额收益具有预测能力,两者呈正相关关系,这种预测能力在考虑市场分割、流动性、经济周期以及不同特质风险度量方法后依然存在。     

股票资产波动成分分解及特质风险波动效应研究

采用我国股票市场的个股数据,应用波动分解的方法计算并分解出股票资产组合三个层面的波动成分。经过实证检验以及对特质风险波动效应的建模分析,发现股票特质风险是我国股票资产价格非理性波动的主要风险来源,它与资本市场的信息不确定性、投资者行为存在着确实的内在联系。因此,需根据我国股市的特点以及股票特质风险自身的波动规律,强化信息披露机制,建立上市公司强制分红制度,并加强对投资者的信息交流与教育引导。     

账面损益如何影响特质波动率与股票收益相关性?——基于我国A股市场的实证研究

本文以1998—2018年A股面板数据为研究样本,使用投资组合分析方法和Fama-MacBeth横截面回归模型,基于前景理论研究账面损益对特质波动率与股票收益相关性的影响。实证研究发现:股票账面损益会显著影响特质波动率与期望收益的相关关系,特质波动率与期望收益在账面收益情况下比在账面损失下呈现出更强的负相关性。并且该结果在考虑了股票价格偏差、最大日收益率和短期收益反转等因素的影响后,依然稳健。该研究结果表明,相较于账面损失,投资者在账面收益情况下表现出更强的风险偏好。     

波动溢出网络视角的金融风险传染研究

当前各类经济风险交叉关联,金融系统的风险溢出效应备受关注,为刻画我国金融系统性风险传染的路径特征,本文从波动溢出网络的视角分析金融系统内部的风险传染机制。首先使用广义动态因子模型对收益波动的共同波动率成分和特质性波动率成分进行区分。然后,根据货币市场、资本市场、大宗商品交易市场、外汇市场、房地产市场和黄金市场之间的特质性波动溢出效应,利用基于TVP-VAR模型的方差分解溢出指数分析金融系统波动溢出的动态联动性和风险传递机制。在分析方向性波动溢出效应的基础上,采用方差分解网络方法构建起信息溢出复杂网络,从网络视角分析金融系统内部的风险传染特征。实证研究发现,房地产市场和外汇市场的净溢出效应绝对值相较于其他市场更大,其受其他市场风险冲击的影响强于对外风险溢出效应,而股票市场的单向对外风险溢出效应强度最大。在波动溢出的基础上,进一步考虑股市波动率指数与其他市场波动率指数进行投资组合的资产配置权重,计算了波动率指数投资组合的最优组合权重和对冲策略。研究结论有助于更好地理解我国金融系统的风险传染机制,对监管机构加强宏观审慎监管、投资者规避投资风险具有重要意义。     

我国养老产业发展“拐点”研判——基于多案例研究的典型事实

随着人口老龄化进程加速,我国的养老需求结构正在从生存型向发展型转变,这将为养老产业的发展带来广阔的市场空间,但当前我国养老产业发展相对滞后,仍面临严重的发展困境。我国养老产业发展的“拐点”何时到来？为回答好这个问题,本文以案例研究和实证分析相结合的研究框架,首先,以法、德、日、美四国为例,系统梳理其养老产业发展历程,总结归纳出养老产业发展“拐点”出现的共性特征;其次,聚焦日本养老产业发展轨迹,重点关注其介护险实施前后养老产业相关重要指标变化;最后,选取九个养老产业相关指标,基于指数平滑、灰色模型等方法对中国养老产业未来情况进行预测,并与日本可比时期指标情况进行比较,判断中国养老产业“拐点”出现的可能时间。研究发现：养老产业发展“拐点”的出现具有四个共性特征,分别是三支柱养老金体系改革、长护险制度全面实施、多元化服务助推医养结合、代际转换背后的产业增量机会,而中国养老产业发展“拐点”可能出现的窗口期将在2026—2030年间。     

流动性资产和负债占比波动与银行破产的关系研究——来自美国银行业的经验证据及银行破产倾向的分析

本文首先选取美国存款保险公司(FDIC)披露的7309家银行2006-2013年上半年的季度财务数据,将其分为破产和未破产两组,研究流动性资产和流动性负债总额分别占总资产和总负债的占比波动幅度与银行破产的关系.分组研究表明:破产银行的流动性资产占比波动性在所有项目的占比波动中最大,呈现出“先升后降”具有“拐点”的走势.并对破产银行组中在统计期间内破产的全部484家破产银行进行单个银行流动性资产占比波动分析,得出了与分组研究一致的结论.其次,文章提出按照流动性资产占比波动率的极差R值将银行的破产倾向量化并分为“标准级、风险级和破产级”三个等级的构想,对样本银行中未破产的6825家银行的破产倾向进行了等级划分,以实现通过量化破产倾向等级、预测破产发生时间对银行破产进行预警的目标.最后,运用2007-2012年的数据对我国15家上市银行的破产倾向进行了研究.     

商品市场不可生成波动率的实证研究

Trolle(2008)指出,商品市场风险分为可以由期货对冲的风险和不可以由期货而由期权来对冲的风险,对应地也就将市场的波动划分为可生成的波动和不可生成的波动。在检验不可生成的波动的存在性时,依据USV(Unspanned Stochastic Volatility,可生成随机波动率)模型,以Trolle(2008)设定的研究框架来进行实证分析,通过COMEX黄金、NYMEX原油以及使用不同于文献记录的市场风险代理变量表示方式计算的上海期货交易所阴极铜的建模结果,发现国内外市场均存在不可生成的波动,USV特征的存在性也为中国市场推出期权提供了理论支持。     

Stock markets’ bubbles burst and volatility spillovers in agricultural commodity markets

Our paper focuses on commodity financialization and the gradual integration between commodity and financial markets, investigating to what extent shocks in stock markets impact commodity price volatility, and the persistency of the phenomenon. To this end, we estimate Volatility Impulse Response Function from stock markets to agricultural commodity markets over a symmetric window before and after two of the most important bubble bursts since the new millennium, the 2000 dot.com bubble and the 2008 financial crises. Results highlight that volatility spillover increased significantly after the 2008 financial crises, signalling a rising interconnection between financial and agricultural commodity markets.     

Investment portfolio balancing: application of a generic self-organizing fuzzy neural network (GenSoFNN)

In contrast to short-term stock trading, portfolio managers are interested in the medium- to long-term peaks and troughs of the stock price cycles as signals to balance their stock portfolios – the predicted trough is the signal to buy the stock and the predicted peak is the signal to sell the stock. As statistical models are generally inadequate or incapable of providing such portfolio balancing signals, we propose using the generic self-organizing fuzzy neural network (GenSoFNN)—a fuzzy neural system – as a tool for portfolio balancing. The network adopts the supervised learning approach to detect inflection points in the stock price cycles, and a modified locally weighted regression algorithm is employed to smooth the stock cycles. The GenSoFNN-based portfolio balancing system was evaluated with experiments conducted using 23 stocks from the New York Stock Exchange and NASDAQ, and the results showed an average profit return of 65.66%. The contributions of the proposed GenSoFNN intelligent portfolio balancing system are twofold: it can be used as an efficient trading solution and it can provide decision support in trading via its generated rules. Copyright © 2009 John Wiley & Sons, Ltd.     

ETF上市对中小企业板市场质量影响的研究

本文探讨中小企业板交易型开放式指数基金（中小板ETF）上市交易对市场质量的影响。研究结果发现：中小板ETF上市交易后，以Amivest比率衡量的中小企业板价格指数（中小板P指数）的流动性是增加的；以GK波动值衡量的中小板P指数的波动性是减小的：市场效率系数法与暂时性价格变动效果分析结果均显示：中小板ETF上市交易后，中小板P指数定价的有效性得到提升。综合来看，引入ETF交易后，中小企业板市场的整体质量变好。     

Volatility spreads and earnings announcement returns

Prior research documents that volatility spreads predict stock returns. If the trading activity of informed investors is an important driver of volatility spreads, then the predictability of stock returns should be more pronounced during major information events. This paper investigates whether the predictability of equity returns by volatility spreads is stronger during earnings announcements. Volatility spreads are measured by the implied volatility differences between pairs of strike price and expiration date matched put and call options and capture price pressures in the option market. During a two-day earnings announcement window, the abnormal returns to the quintile that includes stocks with relatively expensive call options is more than 1.5% greater than the abnormal returns to the quintile that includes stocks with relatively expensive put options. This result is robust after measuring volatility spreads in alternative ways and controlling for firm characteristics and lagged equity returns. The degree of announcement return predictability is stronger when volatility spreads are measured using more liquid options, the information environment is more asymmetric, and stock liquidity is low.     

INVESTOR EXPECTATIONS OF VOLATILITY INCREASES AROUND LARGE STOCK SPLITS AS IMPLIED IN CALL OPTION PREMIA

Recent studies find abnormal common stock price behavior associated with ex-dates of stock splits. Volatility increases are substantia) and abrupt. This study extends previous analyses to the options market by examining investor perceptions of volatility increases through implied standard deviations of returns. Investors fail to anticipate volatility increases until the ex-date. Furthermore, abnormal option returns are present. The increased volatility and these results suggest option market inefficiency.     

股市与债市波动溢出效应的机理研究——基于金融资源配置效率的视角

股市和债市波动溢出效应是金融市场波动的基本特征,研究其机理能够更清晰认识两个市场的价格传导机制和交互波动关系。针对目前研究缺乏系统性等问题,本文从资金、价格及风险等角度研究股市与债市的关联性,分析两个市场存在波动溢出的理论基础;用行为金融学解释波动溢出的产生机理;最后,阐明波动溢出效应与金融资源配置效率的关系。研究发现,它是引导社会资金在资本市场中实现二次配置、提高金融资源配置效率的重要途径。     

Uncertainty,market structure,and liquidity

In this study we show that market uncertainty [measured by the Chicago Board Options Exchange Market Volatility Index (VIX)] exerts a large market-wide impact on liquidity, which gives rise to co-movements in individual asset liquidity. The effect of VIX on stock liquidity is greater than the combined effects of all other common determinants of stock liquidity. We show that the uncertainty elasticity of liquidity (UEL: percent change in liquidity given a 1% change in VIX) has increased around regulatory changes in the US markets that increased the role of public traders in liquidity provision, reduced the minimum allowable price variation, weakened the affirmative obligation of NASDAQ dealers, and abolished the specialist system on the NYSE.     

Sudden changes in volatility in emerging markets: The case of Gulf Arab stock markets

This article examines sudden changes in volatility for five Gulf area Arab stock markets using the iterated cumulative sums of squares (ICSS) algorithm and analyzes their impacts on the estimated persistence of volatility. This algorithm identifies large shifts in volatility of the stock markets during the weekly period 1994 to 2001. In contrast to Aggarwal et al. [Aggarwal, R., Inclan, C., & Leal, R., 1999, Volatility in emerging markets. Journal of Financial and Quantitative Analysis 34, 33-55], this paper found that most of the Gulf Arab stock markets are more sensitive to major global events than to local and regional factors. The 1997 Asian crisis, the collapse of oil prices in 1998 after the crisis, the adoption of the price band mechanism by OPEC in 2000, and the September 11th attack have been found to have consistently affected the Gulf markets. Accounting for these large shifts in volatility in the GARCH(1,1) models significantly reduces the estimated persistence of the volatility in the Gulf stock markets.     

Reference Point Theory and Pursuit of Deals

Target and bidder reference points have separate and joint effects on merger deals. A firm whose stock price is more distant from its 52‐week high reference point is less likely to attract bids but has a greater likelihood of being acquired by its own managers (vs unaffiliated bidders). Firm propensity to submit a bid increases if its prevailing stock price is closer to its 52‐week high. When both parties’ reference points are close to their current stock prices, they are more willing to complete a deal. Hostile deals result when the bidder's stock price is closer to its reference point.     

Heston stochastic vol-of-vol model for joint calibration of VIX and S&P 500 options

A parsimonious generalization of the Heston model is proposed where the volatility-of-volatility is assumed to be stochastic. We follow the perturbation technique of Fouque et al [Multiscale Stochastic Volatility for Equity, Interest Rate, and Credit Derivatives, 2011, Cambridge University Press] to derive a first-order approximation of the price of options on a stock and its volatility index. This approximation is given by Heston’s quasi-closed formula and some of its Greeks. It can be efficiently calculated since it requires to compute only Fourier integrals and the solution of simple ODE systems. We exemplify the calibration of the model with S&P 500 and VIX data.