成交量和回报率对信息扰动的市场反应研究——以中国A股市场为例

用BVAR和BMAR模型及脉冲—响应分析方法来考察中国股票市场上成交量和回报率对信息扰动的动态反应情况得出,公共扰动和永久性扰动是回报率的主要决定因素,而非公共扰动和暂时性扰动则是成交量的主要决定因素。但是公共扰动和永久性扰动对成交量有明显影响;非公共扰动和暂时性扰动对回报率有明显影响。     

Linkages among European and world stock markets

Causal relations and dynamic interactions among equity returns in ten countries for the period 1983–1994 are analysed. An innovation accounting approach based on a multivariate vector autoregressive (VAR) model is used to estimate the proportion of each market return's forecast error attributable to innovations in foreign market returns. Three major results appear. The variance decompositions indicate a strong degree of economic interaction among stock markets. The US stock market has a considerable influence on stock market performance in almost every country, while there is no substantial inter-continental influence from the European stock markets on the world's two largest equity markets in New York and Tokyo. Finally, the pattern of the impulse-response functions illustrates a rapid international transmission of stock market events, supporting the hypothesis of international stock market efficiency.     

Re-Examining the Consumption–Wealth Relationship: The Role of Model Uncertainty

This paper discusses the consumption–wealth relationship. We use data on consumption, assets, and labor income and a vector error correction framework. This framework defines a set of models that differ in the number of co-integrating vectors, the form of deterministic components and lag length. Further models can be defined through parametric restrictions and, in particular, interest centers on a weak exogeneity restriction that says that the co-integrating residuals do not affect consumption and income directly. Key results in previous work relate to the roles of permanent and transitory shocks in driving wealth and how consumption responds to these shocks. We investigate the robustness of these results to model uncertainty and argue for the use of Bayesian model averaging. We find that there is a large degree of model uncertainty. Whether this uncertainty has important empirical implications depends on the researcher's attitude toward the theory used to motivate a co-integrating relationship between consumption, assets and income. If we work with models consistent with this theory and impose the weak exogeneity restriction, we find precisely estimated results that show that permanent shocks have only a small role in driving assets and that the predominant transitory shocks have little effect on consumption. These findings are consistent with the previous literature. However, if we work with a broader set of models and let the data speak, we find that the exact magnitude of the role of permanent shocks is hard to estimate precisely. Thus, although some support exists for the view that their role is small, we cannot rule out the possibility that they have a substantive role to play.     

Liquidity shocks and real GDP growth: Evidence from a Bayesian time-varying parameter VAR

We examine the dynamic impact of liquidity shocks resonating in stock and housing markets on real GDP growth. We fit a Bayesian time-varying parameter VAR model with stochastic volatility to US data from 1970 to 2014. GDP becomes highly sensitive to house market liquidity shocks as disruptions in the sector start to emerge, yet more resilient to stock market liquidity shocks throughout time. We provide substantial evidence in favour of asymmetric responses of GDP growth both across the business cycle, and among business cycle troughs. Stock and house market liquidity shocks explain, on average, 17% and 35% of the variation in GDP during the Great Recession, respectively.     

The effects of oil price shocks on U.S. stock order flow imbalances and stock returns

This paper investigates for the first time the effects of oil demand shocks and oil supply shocks on stock order flow imbalances leading to changes in stock returns. Through the estimation of a structural VAR model, positive oil demand shocks are able to explain almost 36% of the observed variation in the daily average stock order flow imbalances measured by the buy/sell trades ratio; which consequently lead to a negative rather than positive stock returns reaction. In contrast, oil supply shocks exhibit a negative and marginally significant effect on stock order flow imbalances. Our aggregate analysis suggests that positive shocks on stock order flow imbalances are negatively related to stock returns. These effects are stronger for oil-related sectors when compared with the rest of the equities sectors.     

Currency Returns, Intrinsic Value, and Institutional-Investor Flows

We decompose currency returns into (permanent) intrinsic‐value shocks and (transitory) expected‐return shocks. We explore interactions between these shocks, currency returns, and institutional‐investor currency flows. Intrinsic‐value shocks are: dwarfed by expected‐return shocks (yet currency returns overreact to them); unrelated to flows (although expected‐return shocks correlate with flows); and related positively to forecasted cumulated‐interest differentials. These results suggest flows are related to short‐term currency returns, while fundamentals better explain long‐term returns and values. They also rationalize the long‐observed poor performance of exchange‐rate models: by ignoring the distinction between permanent and transitory exchange‐rate changes, prior tests obscure the connection between currencies and fundamentals.     

Time-varying risk preferences and emerging market co-movements

This paper examines how shocks can transmit across international stock markets through the channel of time-varying investor risk preferences. We highlight the effects of this channel by comparing the conventional constant relative risk aversion utility function with the habit-formation utility function of Campbell and Cochrane (J. Pol. Econ. 107 (1999) 205). Calibrating our model with data from Argentina, Korea and Mexico, we find that in the presence of time-varying investor risk preferences, market integration generates a substantial increase in cross-country co-movements of stock returns.     

Consumption, the persistence of shocks, and asset price volatility

In a general equilibrium setting, a temporary component in consumption introduces a wedge between the volatility of equity returns and the volatility of consumption growth. This paper explores the asset pricing consequences of this property in a model in which consumption is the sum of a permanent and a transitory component. Permanent shocks are assumed to be rare events, while transitory shocks follow a diffusion process. When calibrated to US annual data, the model matches first and second moments of equity and bond returns for preference parameters within acceptable bounds. Permanent and transitory shocks together explain the equity premium, while transitory shocks alone explain the excess volatility of returns.     

Characteristics of permanent and transitory returns in oil-sensitive emerging stock markets: The case of GCC countries

The estimates suggest that for both return components there exists a statistically significant high volatility regime for all the Gulf Cooperation Council (GCC) stock markets and the oil market. On the other hand, the results for the low volatility state of both components are mixed. The individual GCC markets vary in terms of sensitivity to volatility and its duration; with Saudi Arabia and Oman having the highest overall return volatility. All the GCC markets are much less volatile than that of the more open, crisis-ridden, oil-exporting Mexico. All GCC returns move in the same direction, whether in terms of total return, fundamentals or fads under both volatility regimes. The correlations between themselves and with Mexico, the oil price and the Morgan Stanley Capital International Index (MSCI) returns are weak compared to the correlations among stock returns of Germany, Japan UK and the US [Bhar, R., Hamori, S., 2004. Empirical characteristics of the permanent and transitory components of stock returns: analysis in a Markov-switching heteroscedasticity framework. Economics Letters 82, 157–165]. Mexico has considerably higher correlation with both MSCI and the oil price than all the GCC countries.     

How do oil supply and demand shocks affect Asian stock markets?

This paper examines how oil market shocks affect Asian stock prices using the structural vector autoregression (VAR) approach. Global oil supply and demand shocks are disentangled using sign restrictions and elasticity bounds. Oil price increases are bad news only if the source is from oil-market-specific demand shifts. Northeast Asian stock markets are more resilient as investors’ expectation of continued economic growth outweighs the adverse effect of higher oil prices. Increased global economic activity also stimulates stock prices. Global oil shocks are more important in explaining variability in Asian stock returns compared with the United States, suggesting different dynamics in Asia.     

Common and country-specific components in national stock prices

Previous studies on cointegration among national stock markets show conflicting results. This paper designs a general state space model to investigate the importance of a common world-wide component and the existence of country-specific components in national stock market indices. For G7 countries, there exist country-specific permanent and transitory components. Based on a variance decomposition analysis, Germany, Italy, and Japan's country-specific permanent shocks account for about half of their total permanent shocks. Most of France, Germany, and the United Kingdom's transitory shocks are country-specific. G7 countries do not seem to cointegrate around one common stochastic trend, and potential long-run international diversification benefits still exist.     

Modelling dynamic dependence and risk spillover between all oil price shocks and stock market returns in the BRICS

This paper investigates the dynamic dependence and risk spillover between BRICS stock returns and different types of oil shocks, combining the Structural VAR model and time-varying copula-GARCH-based CoVaR approach. Our findings indicate that the dependence between BRICS stock returns and oil shocks is time-varying and exhibits different behaviours depending on the shock types in the oil market. In general, the shape of the CoVaRs in each country is comparatively different, depending on its special market situation and domestic policies. There is significant risk spillover from oil-specific demand shock to stock returns in all the BRICS countries. Finally, in Brazil, Russia and India, there is a significant asymmetric effect between upside and downside risk spillover based on oil aggregate demand shock and oil-specific demand shock.     

Causal Relations Among Stock Returns,Interest Rates,Real Activity,and Inflation

Using a multivariate vector-autoregression (VAR) approach, this paper investigates causal relations and dynamic interactions among asset returns, real activity, and inflation in the postwar United States. Major findings are (1) stock returns appear Granger-causally prior and help explain real activity, (2) with interest rates in the VAR, stock returns explain little variation in inflation, although interest rates explain a substantial fraction of the variation in inflation, and (3) inflation explains little variation in real activity. These findings seem more compatible with Fama (1981) than with Geske and Roll (1983) or with Ram and Spencer (1983) .     

What Drives Firm‐Level Stock Returns?

I use a vector autoregressive model (VAR) to decompose an individual firm's stock return into two components: changes in cash-flow expectations (i.e., cash-flow news) and changes in discount rates (i.e., expected-return news). The VAR yields three main results. First, firm-level stock returns are mainly driven by cash-flow news. For a typical stock, the variance of cash-flow news is more than twice that of expected-return news. Second, shocks to expected returns and cash flows are positively correlated for a typical small stock. Third, expected-return-news series are highly correlated across firms, while cash-flow news can largely be diversified away in aggregate portfolios.     

When units roots matter: excess volatility and excess smoothness of long-term interest rates

This paper re-examines volatility tests of the expectations model of the term structure of interest rates. In a multivariate vector autoregression (VAR) including interest rates, prices, money and output, we find that the long-term interest rate overreacts to all transitory shocks, and underreacts to all permanent shocks, irrespective of the number of unit roots and the cointegration structure in the system.     

Monetary Policy, Term Structure and Asset Return: Comparing REIT, Housing and Stock

This paper confirms that a regime-switching model out-performs a linear VAR model in terms of understanding the system dynamics of asset returns. Impulse responses of REIT returns to either the federal funds rate or the interest rate spread are much larger initially but less persistent. Furthermore, the term structure acts as an amplifier of the impulse response for REIT return, a stabilizer for the housing counterpart under some regime, and, perhaps surprisingly, almost no role for the stock return. In contrast, GDP growth has very marginal effect in the impulse response for all assets.     

Sampling interval and estimated betas: Implications for the presence of transitory components in stock prices

We provide a theoretical framework to explain the empirical finding that the estimated betas are sensitive to the sampling interval even when using continuously compounded returns. We suppose that stock prices have both permanent and transitory components. The discrete time representation of the beta depends on the sampling interval and two components labeled “permanent and transitory betas”. We show that if no transitory component is present in stock prices then no sampling interval effect occurs. However, the presence of a transitory component implies that the beta is an increasing (decreasing) function of the sampling interval for more (less) risky assets. In our framework, assets are labeled risky if their “permanent beta” is greater than their “transitory beta” and vice versa for less risky assets. Simulations show that our theoretical results provide good approximations for the estimated betas in small samples. We provide empirical evidence about the presence of negative serial correlation and mean reversion in the returns of the portfolios considered. We discuss why our model is better able to provide an explanation for this sampling interval effect than other models in the literature.     

Testing weak exogeneity in multiplicative error models

Empirical market microstructure literature widely employs the non-linear and non-Gaussian multiplicative error class of models (MEMs) in modelling the dynamics of trading duration and financial marks. It routinely maintains the weak exogeneity of duration vis-à-vis marks in estimations. However, microstructure theory states that trade duration, volume and transaction prices are simultaneously determined. We propose Lagrange-multiplier (LM) tests for weak exogeneity for the MEMs. Our LM tests are extensions of the weak exogeneity tests applicable to VAR or VECM models with Gaussian distributions. Empirical assessments show that (i) weak exogeneity is widely rejected by the data in the MEMs and (ii) the failure of weak exogeneity seriously biases parameter estimates. We hope our tests will be of interest in future empirical applications.     

The Comovement of US and UK Stock Markets

US and UK stock returns are highly positively correlated over the period 1918–99. Using VAR‐based variance decompositions, we investigate the nature of this comovement. Excess return innovations are decomposed into news about future dividends, real interest rates, and excess returns. We find that the latter news component is the most important in explaining stock return volatility in both the USA and the UK and that stock return news is highly correlated across countries. This is evidence against Beltratti and Shiller's (1993) finding that the comovement of US and UK stock markets can be explained in terms of a simple present value model. We interpret the comovement as indicating that equity premia in the two countries are hit by common real shocks.     

CO-MOVEMENTS IN INTERNATIONAL EQUITY MARKETS

We examine the co-movements of equity returns in four major international markets by characterizing the time-varying cross-country covariances and correlations. Using a generalized positive definite multivariate GARCH model, we find that the Japanese and U.S. stock markets have significant transitory covariance, but zero permanent covariance. The other pairs of markets examined display significant permanent and transitory covariance. We also find that, while conditional correlations between returns are generally small, they change considerably over time. An event analysis suggests that basing diversification strategies on these conditional correlations is potentially beneficial.