Animal Behavior in Capital markets: Herding formation dynamics,trading volume,and the role of COVID-19 pandemic

This paper provides new evidence on herding behavior. Using daily frequency data for 336 US listed firms over a five-year period, we investigate three important elements of financial herding behavior. First, trading volume, representing market interest, as a significant variable in capital markets apart from stock prices. Second, herding dynamics since herding formation is a dynamic process. Third, the reaction of possible financial herding to exogenous events-threats, as we use the pandemic event in order to investigate a market under stress. Even though the benchmark herding model used does not provide evidence of herding behavior, our results verify the significance of the above herding elements. We also find that trading volume and positive changes in trading volume result in increased cross-sectional absolute deviation (CSAD). Most importantly, we find that herding behavior is evident during the COVID-19 pandemic confirming that investors tend to herd during major crisis periods.     

Herding in the bad times: The 2008 and COVID-19 crises

The objective of this paper is to analyze the imitation behavior of investors in especially convulsed periods, such as the 2008 financial crisis and the recent global pandemic, both of which could affect investors' emotions and behavior, although both have different characteristics and might have different implications. The cross-sectional dispersion of returns is used to measure the level of herding in the markets of Spain and Portugal, using a survivorship-bias-free dataset of daily stock returns during the period January 2000–May 2021, in turn divided into several sub-periods classified as pre-2008 crisis, 2008 crisis, post-2008 crisis, Covid-19 and post Covid-19. Additionally, the existence is studied of differences between days of positive and negative returns, or between days of high volatility compared to the rest, and whether the cross-sectional dispersion of returns in one market is affected by the cross-sectional dispersion of returns in the other market. The results indicate that herding appears with greater intensity in periods prior to the crisis, disappearing during the financial crisis and reappearing, although with less intensity, after it, while it is not generally detected in Covid-19 times. However, herding behavior can be observed in the market during the pandemic on high volatility days.     

Herding behavior,market sentiment and volatility: Will the bubble resume?

This paper aims to investigate herding behavior and its impact on volatility under uncertainty. We apply a cross-sectional absolute deviation approach as well as Quantile Regression methods to capture the herding behavior in daily and monthly frequencies in US markets over several time-periods including the global financial crisis. In a novel attempt we modify the empirical CSAD herding modeling by introducing implied volatility as a measure of agent risk expectations. Our findings indicate that herding tends to be intense under extreme market conditions, as depicted in the upper high quantile range of the conditional distribution of returns. During crisis periods herding is observed at the beginning of the crisis and becomes insignificant towards the end. The US market herding behavior exhibits time-varying dynamic trading patterns that can be attributed e.g., to overconfidence or excessive “flight to quality” features, mostly observed in the aftermath of the global financial crisis. Moreover, implied volatility reveals asymmetric patterns and plays a key role in enforcing irrational behavior.     

Country and industry convergence of equity markets: International evidence from club convergence and clustering

This study employs the panel convergence methodology developed by Phillips and Sul (2007) to explore the convergence dynamics of international equity markets. The analysis considers both country and industry effects. While traditional portfolio management strategies usually follow a top-down procedure, assuming that country-level effects drive financial aggregates (e.g., stock returns) our empirical results suggest that the equity markets of 37 of the 42 counties in our sample do form a unified convergence club. The empirical findings, however, also show more numerous stock-price convergence clubs in certain industries. That is, country factors play a more important role in explaining the actual convergence in real stock prices than industry factors. Conversely, the volatility of stock prices exhibits much more evidence of convergence than stock prices. These findings should assist portfolio managers in the design and implementation of appropriate portfolio management strategies. Regulatory authorities also can benefit in the design of financial regulation.     

A股、H股市场羊群行为实证研究

本文采用分散度指标和偏离度指标对2005-2008年间交叉上市A股和H股市场的羊群行为进行了实证检验．发现A股市场存在羊群效应,但未发现H股市场上的羊群效应。本文认为两地市场在投资者理念、市场结构、信息披露、政府监管方面的差异是造成这种差异的根源,并在此基础上提出了政策建议。本文的研究将对企业在两地市场上投融资,各类投资者规避风险获得稳定收益,两地金融市场的一体化乃至中国资本市场的长远发展具有一定指导意义。     

Speculative behavior and the dynamics of interacting stock markets

We develop a simple agent-based financial market model in which heterogeneous speculators apply technical and fundamental analysis to trade in two different stock markets. Speculators׳ strategy/market selections are repeated at each time step and depend on predisposition effects, herding behavior and market circumstances. Simulations reveal that our model is able to explain a number of nontrivial statistical properties of and between international stock markets, including bubbles and crashes, fat-tailed return distributions, volatility clustering, persistent trading volume, coevolving stock prices and cross-correlated volatilities. Against this background, our model may be deemed to have been validated.     

金融市场羊群行为理论研究综述

近10年来,对金融市场上羊群行为的研究迅速成为金融经济学的热点之一。文章介绍了金融市场上羊群行为的概念,系统地回顾了羊群行为的理论研究成果,并展望了金融市场羊群行为理论研究的未来发展方向。     

What drives herding in oil-rich,developing stock markets? Relative roles of own volatility and global factors

The main goal of this paper is to formally establish the volatility-herding link in the developing stock markets of the oil-rich GCC countries by examining how market volatility affects herd behavior after controlling for global factors. Using a regime-switching, smooth transition regression model (STR), we find significant evidence of herding in all Gulf Arab stock markets, with the market volatility being the more paramount factor governing the switches between the extreme states of non-herding and herding. The global variables comprised of the U.S. stock market performance, the price of oil and the US interest rate as well as the risk indexes including the CBOE Volatility Index (VIX) and the St. Louis Fed's Financial Stress Index (FSI) are found to be significant factors governing the transition to herding states. The findings stress the effect of contagion in financial markets, despite the restrictions established by the GCC policymakers in order to protect their markets.     

Agency costs in the banking industry: An examination of ownership behavior,leverage and dividend policies

This paper examines agency theory arguments in the banking industry by analyzing the effect of four variables that proxy for agency costs—earnings volatility, managers' portfolio diversification losses, bank size, and standard deviation of bank equity returns—on the three financial policy variables of managerial stock ownership, leverage, and dividend yield. It is one of the first studies that examines the determination of financial policy variables, in light of agency concerns, in the banking industry. The study examines the largest 104 U.S. banks during the period 1985–1989. Evidence suggests that bank size and a measure of the managers' portfolio diversification opportunity set affect the bank's level of managerial stock ownership, leverage and dividends.     

Learning by doing: Active employer sponsored retirement savings plan participation and household wealth accumulation

This paper investigates the impact of household exposure to employer pension plan features using the Health and Retirement Survey. We investigate whether exposure to active management (choice) or participation in plan-sponsored financial education seminars impacts household portfolio allocations and wealth. We consider interactions between pension design and investment patterns outside of workers’ pension plans, utilizing two parametric estimators: the random effects probit and the multivariate probit. We extend our results non-parametrically via propensity score matching. We find repeated evidence that both of the plan features improve asset allocations and financial outcomes for recent retirees, especially when used together.     

Impact of diversification on the distribution of stock returns: International evidence

In the past, stock returns are often assumed to be normally distributed. Potential gains from international portfolio diversification are thus based on a mean-variance framework. However, numerous empirical results reveal that stock returns are actually not normally distributed. Although previous studies found that both skewness and kurtosis can be rapidly diversified away, these results are only valid for a random sample of a given portfolio size. This paper studies the joint effect of diversification and intervaling on the skewness and kurtosis of eleven international stock market indexes with a holding period spanning from one to six months. A complete set of all possible combinations of portfolios is used. It is found that diversification does not reduce either skewness or kurtosis. As the portfolio size increases, portfolio returns become more negatively skewed and more leptokurtic. As a result, a rational investor may not gain from international diversification.     

Homeownership and mixed-asset portfolio allocations

Homeownership represents both a consumption and an investment decision for individuals. Considering the investment benefits of the home, we estimate the total returns and risk associated with the investment in single-family homes. Then, using a mean–variance utility function, we consider the impact of homeownership and mortgage loan financing on the optimal asset allocation decisions of individuals and contrast this with advice that does not include the home as part of the portfolio. While optimal portfolio weights are dependant upon both the degree of risk aversion of the individual investor and the relative importance of the home in the overall net worth picture, we show that, in general, the higher the home-to-net worth ratio, the higher the optimal portfolio allocation to stock. For most investors, including the home in the optimization decision leads to higher allocations to risky stock than suggested by traditional advice that ignores the home.     

Portfolio choice,behavioral preferences and equity home bias

We provide a plausible explanation of aggregate portfolio behavior, in a framework where economic agents have behavioral (narrow framing) preferences. The representative agent derives utility not only from consumption (standard models) but also from risky financial wealth fluctuations. Moreover, the investor frames the stock market risk narrowly and has loss averse preferences. We numerically solve, for the foreign equity share, a simple model of international portfolio choice, providing a possible explanation for the equity home bias puzzle. Only economic agents able to process correctly information deriving from stock markets exploit the diversification opportunities provided by international financial markets.     

An agent-based early warning indicator for financial market instability

Inspired by the Bank of America Merrill Lynch global breath rule, we propose an investor sentiment index based on the collective movement of stock prices in a given market. We show that the time evolution of the sentiment index can be reasonably described by the herding model proposed by Kirman in his seminal paper “Ants, rationality and recruitment” (Kirman in Q J Econ 108:137–156, 1993). The correspondence between the index and the model allowed us to easily estimate its parameters. Based on the model and the empirical evolution of the sentiment index, we propose an early warning indicator able to identify optimistic and pessimistic phases of the market. As a result, investors and policy-makers can set different strategies anticipating financial market instability. Investors can reduce the risk of their portfolio while policy-makers can set more efficient policies to avoid the effects of financial instability on the real economy. The validity of our results is supported by means of a robustness analysis showing the application of the early warning indicator in eight different worldwide stock markets.

     

Direct comparison of agent-based models of herding in financial markets

The present paper tests a new model comparison methodology by comparing multiple calibrations of three agent-based models of financial markets on the daily returns of 24 stock market indices and exchange rate series. The models chosen for this empirical application are the herding model of Gilli and Winker (2003), its asymmetric version by Alfarano et al. (2005) and the more recent model by Franke and Westerhoff (2011), which all share a common lineage to the herding model introduced by Kirman (1993). In addition, standard ARCH processes are included for each financial series to provide a benchmark for the explanatory power of the models. The methodology provides a consistent and statistically significant ranking of the three models. More importantly, it also reveals that the best performing model, Franke and Westerhoff, is generally not distinguishable from an ARCH-type process, suggesting their explanatory power on the data is similar.     

Bank herding and systemic risk

Bank herding behavior is often hypothesized to increase systemic risk, but the actual effect is unclear ex-ante from the theory and unknown ex-post from the data. We expand the literature on this topic in several dimensions – posing alternative hypotheses regarding the effects of herding in asset, liability, and off-balance sheet portfolios; developing a novel set of bank-specific, time-varying measures of herding in these portfolios; and empirically testing the relations between bank herding for all three portfolios and bank systemic risk contributions. We find nuanced empirical results that differ by portfolio, bank size class, and periods before versus after TARP.     

基于自由现金流的投资组合研究

本文运用我国股市1998～2006年间的财务报表数据,选择正自由现金流、低自由现金流乘数和低财务杠杆的大公司,对其以自由现金流为基础的投资组合进行了检验。结果显示,以自由现金流为基础的投资组合回报始终优于市场指数,说明在我国股市实行基于自由现金流的投资组合是积极可行的。     

三种Copula-VaR计算方法与传统VaR方法的比较

金融风险测量VaR方法广泛应用于银行等金融机构,Copula技术以其处理非正态联合分布函数所具有的良好性质逐渐成为国内外研究的热点。本文将Copula理论应用于VaR的计算方法,并与传统的VaR方法进行比较,通过美元和欧元组合的实证研究,得到基于Copula的VaR方法能够更加有效地测量风险的结论。     

STOCK‐FLOW INTERACTIONS,DISEQUILIBRIUM MACROECONOMICS AND THE ROLE OF ECONOMIC POLICY

This paper presents the ‘KMGT’ (Keynes–Metzler–Goodwin–Tobin) portfolio model and studies its stability properties. The approach to macrodynamic modelling taken here extends the KMG model of Chiarella and Flaschel (2000) , focusing in particular on the incorporation of financial markets and policy issues. The original KMG model considered three asset markets (equities, bonds and money) but depicted them in a rudimentary way so that they had little influence on the real side of the model. The only financial market influencing the real side of the economy was the money market (via an LM curve theory of interest). Here Tobin's portfolio choice theory models the demand for each asset in such a way that the total amount of assets that households want to hold equals their net wealth, which is a stock constraint attached to portfolio choice. There is also a flow constraint, that the net amount of assets accumulated (liabilities issued) by one sector must equal its net savings (expenditures). The Tobinian macroeconomic portfolio approach characterizes the potential for financial market instability, focusing on the interconnectedness of all three markets. The paper goes on to study the potential for labour market and fiscal policies to stabilize unstable macroeconomies.     

Form of ownership and risk taking in banking: Some evidence from Massachusetts savings banks

In recent years there has been interest in the impact of the form of ownership on the behavior of financial institutions. In the 1980’s, there was a substantial movement away from mutual ownership to stock ownership in the thrift industry. The effect of this conversion process on risk taking and efficiency has been a matter of concern. The purpose of this paper is to examine the experience of savings banks in Massachusetts. A panel of 115 savings banks is analyzed for the years 1985 through 1993, a period that includes both rapid growth and a subsequent severe cyclical decline in property values. The credit quality of loan portfolios is related to the size of the portfolio, the structure of the portfolio, and the ownership status of the bank. Several models are estimated. In all cases, it was found that the cyclical decline in property values resulted in a decline in the credit quality of loan portfolios with a substantially greater impact on those savings banks that converted from mutual to stock status.