基于投资者异质性信念的证券定价模型——对我国股票市场价格的实证检验

投资者异质性信念的相互作用影响着证券价格,证券市场上的各种证券需求与供给关系,往往表现为投资者各种不同信念的对抗和交融。本文以悲观信念（看多）和乐观信念（看空）之间的相互作用为例,研究了异质性信念对资产均衡定价的影响,并以我国股票市场的机构投资者信念为对象进行了实证检验,得出我国股票市场投资者信念与证券价格相互作用的结论。本文的建议是在投资过程中,准确分析市场中投资者的异质性信念结构,尤其是资金雄厚的机构投资者的信念结构至关重要。     

Aggregation of heterogenous beliefs,asset pricing,and risk sharing in complete financial markets

Given a competitive equilibrium in complete asset markets, we propose a method that aggregates heterogeneous individual beliefs into a single “market probability,” which, if commonly shared by investors, generates the same marginal valuation of assets by the market as well as by each individual investor. As a result of the aggregation process, the market portfolio may have to be scalarly adjusted, upward or downward, a reflection of an aggregation bias due to the diversity of beliefs. From a dual viewpoint, the standard construction of an expected utility-maximizing aggregate investor designed to represent the economy in equilibrium, is shown to be also valid in the case of heterogeneous beliefs, modulo the above scalar adjustment of the market portfolio, thereby generating an Adjusted version of the Consumption based Capital Asset Pricing Model (ACCAPM). We analyze how the allocation of aggregate and individual risks relates to deviations of individual beliefs from the aggregate market probability. Finally, we identify the channels through which the distribution of beliefs and other microeconomic characteristics (incomes, attitudes toward risk) across investors impact the pricing of risky assets an may contribute to explaining the equity premium puzzle.     

Beliefs and arbitrage pricing

This paper investigates the necessary restriction on investor beliefs implied by a no-arbitrage price system. In addition, Stone's theorem is invoked to study the existence of equivalent probability measures, and to relate our approach to the existing literature.     

Analysts herding: when does sentiment matter?

Herding among analysts emerges when analysts give priority to their peers’ opinions instead of their own beliefs or information. Some circumstances may enhance or restrain this type of behaviour. We postulate that market sentiment is one of them. This article analyses the effect that investor sentiment may have on analysts’ herding behaviour in the U.K. Our results suggest that ‘easy situations’ such as analysing easy-to-value securities and releasing optimistic information at times of high market sentiment clearly reduce herding practices, whereas herding clearly increases in difficult situations when analysts have to release negative information at moments of high investor sentiment.     

Revisiting the democracy-private investment nexus: Does inequality matter?

Contrary to the predictions of a large theoretical literature, recent cross-country evidence suggests autocracies can generate statistically indistinguishable levels of private investment compared to democracies. We argue that the previous exclusion of inequality explains part of this puzzle. We model current investment as a function of investors’ beliefs about future tax rates, which are conditioned by the constraints on the Executive in setting tax rates and expropriating tax revenues. In democracies, where tax rates reflect the preferences of the median voter, investment declines with rising inequality. In autocracies, investor beliefs about future tax rates reflect the relative power of Elites compared to the Executive. As inequality rises, the increased resources available to Elites constrains the Executive’s ability to expropriate more tax revenues. The heterogeneous determinants of investor beliefs can explain the observed pattern of investment across regime types. We first test our predictions at the macro-level with cross-country data. We then test the behavioral underpinnings of our model with a novel laboratory experiment showing how inequality affects individual-level investment behavior dependent upon regime type. Results from both types of analyses show that when inequality is taken into account autocracies can generate similar levels of investment to democracies.     

Corporate tax avoidance and cost of equity capital: international evidence

ABSTRACT

This study examines the association between firm’s tax avoidance activities and cost of equity capital across 17 countries. Consistent with the prior study based on the U.S. evidence, within strong investor protection countries, the extent of firm’s tax avoidance is negatively associated with its cost of equity capital. This result indicates that strong investor protection induces investors to perceive firm’s tax avoidance activities as the results of efficient tax planning to reduce tax liabilities. To the contrary, we find that the extent of firm’s tax avoidance is positively associated with its cost of equity capital within weak investor protection countries. This result suggests that investors impose equity risk premium on firm’s tax avoidance activities in weak investor protection countries, where agency conflicts prevail more on firm’s tax avoidance activities. As the first international study on the association between firm’s tax avoidance activities and its cost of equity capital, this study contributes to the literature by suggesting that such an association may vary across countries depending on the strength of investor protection within each country of domicile.     

Do Energy Prices Affect U.S. Investor Sentiment?

The current literature has examined the effect of investor sentiment on energy prices, but no study ever has explored the validity of the reverse question. Therefore, this article explore whether energy prices (i.e., crude oil and natural gas prices) affect U.S. investor sentiment, using the methodology of quantile regression. The empirical results document that controlling for a number of U.S. macroeconomic and financial factors, there exists a statistically significant association between oil and natural gas prices and investor sentiment. However, only natural gas prices appear to retain their statistical significance over the majority of quantiles. These findings received robust support under alternative measures of the investor sentiment index.     

The relations among accounting conservatism,institutional investors and earnings manipulation

Most scholars have indicated corporations using accounting conservatism to reduce earnings manipulation, although certain scholars believe that firms have more incentive to increase earnings manipulation. Institutional investors play an important external monitoring role, and affect firm's earnings manipulation. Previous studies adopted accruals as an earnings manipulation proxy to detect the relationship among accounting conservatism, institutional investor shareholdings, and earnings manipulation. We further investigate the relationship among accounting conservatism, institutional investor shareholdings, and earnings manipulation by using Benford's law. Our results indicate that firms with more conservative financial reporting have less probability of engaging in earnings-manipulative activities. We also find the negative association between earnings management and institutional investor shareholdings. However, if corporate financial statements tend toward conservatism, institutional investor shareholdings could increase managers' incentive to manage earnings. Our findings have important implications for investors to make investment decisions.     

The capital asset pricing model in economic perspective

The capital asset pricing model (CAPM) is theoretically incomplete in its demand-side focus, risk-averse investors and internally inconsistent homogeneous beliefs; is not conclusively supported empirically; and yet it legitimizes a notion that investors can earn higher returns by bearing undiversifiable risk. Our article does not merely extend the CAPM with more realistic assumptions, it completes its original framework by including (1) risk-taking investors in the investor population, (2) investors who can have heterogeneous expectations or beliefs – an overlooked but required condition for the CAPM to be an internally consistent and meaningful model of competitive financial asset pricing under uncertainty and (3) a positive-sloped short-run supply curve based on a reasonable interpretation of the nature of financial asset trade. Upon a complete economic interpretation, it is shown that the equilibrium (systematic) risk-rate of return relationship depends on whose aggregate trading activity dominates, risk-averse or risk-taking investors’. There is no universal, or even general, positive relationship between systematic risk and rate of return. This has far-reaching implications for investors and investment advisors who serve them.     

Does High Stock Price Synchronicity Always Hurt Mutual Fund Industry? Sentiment Matters

Investors have agreed that high synchronicity of stock returns adversely influences professional funds' profitability. However, different market conditions where high synchronicity exists may have different effects on this relationship. This study incorporates aggregate investor sentiment as a market condition in the equation to explore whether and when the negative association between synchronicity and fund performance holds. The authors use a sample of actively managed U.S. equity mutual funds from 2000 to 2014 and employ a portfolio of 11 passively managed funds as the benchmark to measure fund performance and fund management skill. They find empirical evidence that synchronicity negatively impacts mutual funds' profitability when the investor sentiment is low. This negative relationship disappears in high-sentiment periods. They also find that in both low- and high-sentiment states, fund managers with superior stock selection skill make more profits from high synchronicity than the average.     

Investor sentiment and the financial crisis: a sentiment-based portfolio theory perspective

The article proposes a portfolio model subjected to a constraint that captures the investor’s goal, with maximum estimation of expected return that is affected by investor sentiment. And we give a solution of the portfolio model by exploring the geometric features. Furthermore, we discuss the relationship between investor sentiment and the financial crisis by analysing the optimal allocation. The results show that: when investor sentiment is low enough, the investor should reject the investment, this condition leads the depression financial market to prevail, then the financial crisis erupts; when investor sentiment is modest, the financial crisis is difficult to erupt unless the decline of investor sentiment is quick and deep; but there is a special status that the financial crisis is caused by other factors rather than by investor sentiment; and only improving investor sentiment cannot move away from the financial crisis.     

Globally evolutionarily stable portfolio rules

The paper examines a dynamic model of a financial market with endogenous asset prices determined by short-run equilibrium of supply and demand. Assets pay dividends that are partially consumed and partially reinvested. The traders use fixed-mix investment strategies (portfolio rules), distributing their wealth between assets in fixed proportions. Our main goal is to identify globally evolutionarily stable strategies, allowing an investor to “survive,” i.e., to accumulate in the long run a positive share of market wealth, regardless of the initial state of the market. It is shown that there is a unique portfolio rule with this property—an analogue of the famous Kelly rule of “betting your beliefs.” A game theoretic interpretation of this result is given.     

Asset pricing and institutional investors with disagreements

We develop a dynamic asset pricing model with two institutional investors who have benchmark incentives and who disagree about the underlying economy. We derive semi-closed form expressions for all equilibrium quantities. We find that the benchmark stock price increases and the non-benchmark stock price decreases with the benchmark incentives. Furthermore, each stock price decreases with its own disagreement and increases with the other stock disagreement. We also show that there is a positive relationship between the co-movement of the stocks and the benchmark incentives, but that this co-movement is negative with the disagreements, owing to the endogenous risk-sharing mechanisms. Moreover, we find that, when one stock disagreement increases, the optimistic institutional investor always takes positions on this stock by shorting the other stock and the bond in order to hedge against the risk of market changes, in line with the pessimistic investor's beliefs.     

后金融危机时代投资者保护实施方式的转换

增强投资者保护水平有利于优化资源配置,而投资者保护水平的变化是一个利益关系的调整过程,因而后金融危机背景下提升投资者保护水平极其必要。而目前在投资者保护的实施方式方面存在着认识上的误区:过于注重投资者保护的公共监管实施,忽视其私人实施。因此,提升投资者保护水平应注重投资者保护实施方式的转换。     

Does investor sentiment dynamically impact stock returns from different investor horizons? Evidence from the US stock market using a multi-scale method

This article uses the investor sentiment index to investigate the Granger causality between investor sentiment and stock returns for the US economy using a multi-scale method. To focus on the local analysis of different investor horizons, bivariate empirical mode decomposition is used to decompose time series of investor sentiment and stock returns at different timescales. We employ the linear and nonlinear integrated Granger causality method to examine the causal relationship of decomposed series on similar timescales. The results indicate both strong bilateral linear and nonlinear causality between longer-term investor sentiment and stock returns. However, there is no strong evidence for correlation of stock returns and investor sentiment on shorter timescales.     

上市银行利用投资者关系管理开展公司营销的探讨

投资者关系管理的核心是上市公司与投资者之间的互动沟通。通过南开大学投资者关系管理评价体系对中国14家上市银行数据的研究发现,目前中国上市银行投资者关系管理总体处于中等水平,在组织设计、互动沟通及投资者关系创新等方面存在不少问题。针对这种现状,上市银行应该在不断提高投资者关系管理水平的基础上,利用投资者关系这一沟通手段开展资本市场公司营销,积极推销自己的投资主题,才能在竞争日益激烈的资本市场上赢得竞争,达到吸引投资者的目的。     

投资者关系管理能够抑制企业违规风险吗？*--基于A股上市公司投资者关系管理的综合调查

文章利用南京大学联合证监会对 A 股上市公司投资者关系管理状况的综合调查数据,切入投资者关系管理的独特视角,实证分析了投资者关系管理与企业违规风险之间的关联及其影响因素。研究发现,投资者关系管理与企业未来的违规倾向呈显著的负向关系,且这种负向关系在控制内生性等问题后依然存在。这表明投资者关系的有效管理能够显著抑制企业的违规风险。影响因素分析结果显示,在抑制企业违规风险方面,投资者关系管理和内部控制质量具有互补作用,而媒体报道、分析师跟踪、公司规模、机构持股等公司可视性因素对投资者关系管理与企业违规风险之间的负向关系并没有显著的影响。文章不仅在理论上拓展了投资者关系管理的研究,而且在实践上对于规范上市公司经营运作、提振投资者信心以及防止金融市场极端波动具有重要的启示意义。     

基于公司视角的公司治理与投资者保护关系的实证研究

本文尝试利用世界银行的调查问卷对我国上市公司的投资者保护指标进行了测定,研究了基于公司视角的投资者保护与公司治理、公司绩效的关系。实证分析表明,基于上市公司的投资者保护水平较低,且在不同行业之间没有显著性差异;投资者保护的二级指标"独立性"和"经理责任"分别与董事会规模显著正相关,表明加强董事会建设有利于提升公司治理的投资者保护效果;二级指标"公平性"与股权集中度显著负相关,表明股权集中不利于公司治理对全体股东的公平对待。实证分析同时提供了投资者保护与公司绩效关系的相反证据,一方面表明投资者保护(表现为公平性指标)有利于促进公司绩效(表现为托宾Q值)提高,另一方面表明投资者保护与公司短期经营绩效之间存在复杂影响因素,需要综合考虑公司内外部环境因素进行系统性分析,并应增加时间序列的数据分析。     

Does mixed-frequency investor sentiment impact stock returns? Based on the empirical study of MIDAS regression model

We examine whether mixed-frequency investor sentiment affects stock returns. In line with recent evidence from China, we find that the aggregate effect and the individual effect of mixed-frequency investor sentiment are statistically significant, and mixed-frequency investor sentiment is more important than the low-frequency one. Moreover, mixed-frequency investor sentiment, which is mixed by high-frequency data, can be more important than the market premium.     

A nonlinear Granger causality test between stock returns and investor sentiment for Chinese stock market: a wavelet-based approach

In this article, we re-examine the causality between the stock returns and investor sentiment in China. The number of net added accounts is used as a proxy for investor sentiment. To mimic the different investment horizons of market participants, we use the wavelet method to decompose stock returns and investor sentiment into time series with different frequencies. Additionally, we test for nonlinear causal relationships based on Taylor series approximation. Our results indicate that there is a one-directional linear causality from stock returns to investor sentiment on the original series, while there is a strong bi-directional nonlinear causality between stock returns and investor sentiment at different timescales.