Financial price fluctuations in a stock market model with many interacting agents

Summary. We consider a financial market model with a large number of interacting agents. Investors are heterogeneous in their expectations about the future evolution of an asset price process. Their current expectation is based on the previous states of their neighbors and on a random signal about the mood of the market. We analyze the asymptotics of both aggregate behavior and asset prices. We give sufficient conditions for the distribution of equilibrium prices to converge to a unique equilibrium, and provide a microeconomic foundation for the use of diffusion models in the analysis of financial price fluctuations.Received: 16 April 2003, Revised: 1 March 2004, JEL Classification Numbers: D40, D84, G10.I thank Peter Bank, Dirk Becherer, Hans Föllmer, Peter Leukert, José Scheinkman, Alexander Schied, Ching-Tang Wu, and seminar participants at various institutions for many suggestions and discussions. Thanks are due to two anonymous referees and the editor, C.D. Aliprantis, for valuable comments which helped to improve the presentation of the results. Financial support of Deutsche Forschungsgemeinschaft via SFB 373, Quantification and Simulation of Economic Processes, Humboldt-Universität zu Berlin, and DFG Research Center Mathematics for Key Technologies (FZT 86) is gratefully acknowledged.     

Currency appreciation and stock market performance: Evidence from China

This paper analyzes the relationship between the change of the exchange rate and the performance of the Chinese stock market after exchange rate regime and split share structure of stock market reformed in 2005, which is important for us to understand the linkages and mechanisms between the two markets deeply. We find that the exchange rate is highly related with the stock market, and there exists long-term cointegration. The results demonstrate that in the long term, the relationship between the two variables mainly belongs to flow-oriented model; Shanghai A Share index is influenced by the exchange rate, yet Shanghai B Share index has shown less indication of long term interrelation with the exchange rate. In the short term, the relationship between the two variables mainly belongs to stock-oriented models, there are inter influence between the stock market and the exchange market. The paper further analyzes the possible influence of different sector indices to exchange rates. Finally, the paper puts forward some advices and policy suggestions.     

股票市场系统动力学分析：以上海股票市场为例

本文突破了传统经济理论研究的线性框架,视股票为一非线性系统,运用分形、混沌等复杂性理论对上海股票市场的系统动力学特征进行实证研究,得出了上海股票市场系统的分形特征、复杂性程度、系统演化类型及稳定性,最后,探讨了这些结论对股票市场的理论与实践意义。     

A vector error correction model of the Singapore stock market

This article examines the long-term equilibrium relationships between the Singapore stock index and selected macroeconomic variables, as well as among stock indices of Singapore, Japan, and the United States. Upon testing appropriate vector error-correction models, we detected that changes in two measures of real economic activities, industrial production and trade, are not integrated of the same order as changes in Singapore's stock market levels. However, changes in Singapore's stock market levels do form a cointegrating relationship with changes in price levels, money supply, short- and long-term interest rates, and exchange rates. While changes in interest and exchange rates contribute significantly to the cointegrating relationship, those in price levels and money supply do not. This suggests that the Singapore stock market is interest and exchanges rate sensitive. Additionally, the article concludes that the Singapore stock market is significantly and positively cointegrated with stock markets of Japan and the United States.     

Understanding the recent performance of China's stock market

Employing time-series extrapolation and an out-of-sample forecast based on a bivariate VAR (vector auto-regression), we argue that the current boom of China's stock market represents a recovery that corrects the previous divergence of the stock market from the aggregate economic performance. Nevertheless, we caution that the speed of the recent rise in stock prices is alarming. If the current speed continues, then the stock market will soon become overheated in the sense that the level of stock prices will exceed the level justified by economic fundamentals.     

International stock market efficiency: a non-Bayesian time-varying model approach

This article develops a non-Bayesian methodology to analyse the time-varying structure of international linkages and market efficiency in G7 countries. We consider a non-Bayesian time-varying vector autoregressive (TV-VAR) model, and apply it to estimate the joint degree of market efficiency in the sense of Fama (1970, 1991). Our empirical results provide a new perspective that the international linkages and market efficiency change over time and that their behaviours correspond well to historical events of the international financial system.     

Electoral information in developed stock market: testing conditional heteroscedasticity in the market model

By about 1988, the consensus among leading health economists was that no meaningful differences existed among hospitals of differences owernership form, and this position was embraced by the Antitrust Division of the US Department of Justice. But behavioural differences among hospitals of different among hospitals of different owernership has continued to be a matter of both academic and judicial interest. Recent empirical studies have concluded that real differences do exist, while many earlier studies reached the opposite conclusion. This contradiction in finding over time, as competition intensified, is exactly opposite to what expense-preference theory would predict. We examine this apparent paradox, using a very general test of behavioural differences by hospital ownership. We find that the omission of location-specific variables can lead to biased estimates of ownership effects, and that no significant behavioural differences exist among private California hospitals in 1986–90, when this source of ownership endogeneity is eliminated.     

Macroeconomic environment,country risk and stock market performance: Evidence for Brazil

The paper aims at providing empirical evidence about (i) the influence of macroeconomic variables and economic policies on country risk and (ii) the influence of macroeconomic variables and country risk on the main Brazilian index of the stock market (Ibovespa). The study analyzes the role that macroeconomic fundamentals plays, but also the role that the credibility of the regime of inflation targeting and the reputation of the central bank play in lessening country risk and in the improvement of the stock market performance. The empirical evidence was obtained through the application of ordinary least squares (OLS), generalized method of moments (GMM) and GMM systems. The results found suggest that monetary policy and public debt management, as well as credibility and reputation affect country risk and the performance of the Brazilian stock market.     

上市公司经营业绩与股市表现研究

上市公司股价波动作为经营情况的反映,经营业绩变动理当成为股价波动的主要影响因素,这也是在证券市场交易中价值投资存在的基石,但是价值投资理念在我国证券市场中的有效性却得到了诸多质疑。正是在此背景下,按照当前多层次的资本市场结构,分别针对主板、中小板以及创业板上市公司进行了实证分析,结果表明上市公司经营业绩并不是引起股价变动的Granger原因。     

Semiparametric EGARCH model with the case study of China stock market

In this paper, we propose a new semiparametric method for GARCH model by combining the EGARCH (1,1) model and local polynomial regression. Based on the idea of two-stage estimate, a link function is estimated by the local polynomial and then the parameters are obtained via the weighted least square method. Finally we apply this method to the Shanghai Composite Index in the China stock market and compared the results with these of EGARCH.     

A portfolio choice model with utility from anticipation of future consumption and stock market mean reversion

This paper studies a consumption and portfolio choice problem of a long-lived investor who derives pleasure not only from current consumption, but also from the contemplation of future consumption. The model assumes that all effects of future consumption on current well being are assumed to enter through a single variable—namely, the “stock of future consumption”—analogously to habit-formation models. The main implications of the model concern the incentives for savings, and the fundamental sources of risk in financial markets. It is shown that, when the stock market exhibits mean reversion, deriving utility from anticipation of future consumption has a tremendous effect on portfolio choice. In particular, mean allocation to stocks is much lower under the proposed preferences relative to the standard preferences, especially for high risk averse investors.     

Regional stock market integration in Singapore: A multivariate analysis

This paper evaluates the time-varying integration of the Singapore stock market in the ASEAN-5 region based on a conditional version of the International Capital Asset Pricing Model (ICAPM) with c-DCC-FIAPARCH parameters. This model allows for dynamic changes in the degree of market integration, regional market risk premium, regional exchange-rate risk premium, and domestic market risk premium. Our findings show several interesting facts. First, the time-varying degree of integration in the Singapore market is satisfactorily explained by the level of trade openness and the term premium of US interest rates, which have recently tended to increase, however these markets remain substantially segmented from the world market. Second, the local market risk premium is found to explain a significant proportion of the total risk premium for emerging market returns. Our findings illustrate several important implications for portfolio hedgers for making optimal portfolio allocations, engaging in risk management and forecasting future volatility in equity markets. Our results are also of interest for both policymakers and investors, with respect to regional development policies and dedicated portfolio investment strategies in the ASEAN-5 region.     

Forecasting volatility in the Chinese stock market under model uncertainty

Volatility forecasting is an important issue in empirical finance. In this paper, the main purpose is to apply the model averaging techniques to reduce volatility model uncertainty and improve volatility forecasting. Six GARCH-type models are considered as candidate models for model averaging. As to the Chinese stock market, the largest emerging market in the world, the empirical study shows that forecast combination using model averaging can be a better approach than the individual forecasts.     

Bayesian model comparison by Markov chain simulation: Illustration using stock market data

The paper illustrates the computation of marginal likelihoods and Bayes factors when Markov Chain Monte Carlo has been used to produce draws from a model’s posterior distribution. The method is based on Raftery (1996) and does not require that Gibbs sampling is used or conditional posterior distributions are available in closed form. Models used include a normal finite mixture, a GARCH and a Student t -model as alternative models for the Standard and Poor’s stock returns.     

Currency exposures of the oil and natural gas stock prices in the Hushen-300 stock market： A nonlinear model approach

The paper embarks to investigate the relationship between currency risk and stock prices of the oil and natural gas exploitation industry in the value-weighted Hushen-300 stock market, by applying the standard Capital Asset Pricing Model （CAPM） and nonlinear exchange rate exposure model to the Renminbi against US dollar. The results show that the currency exposure does vary in the oil-gas stock prices throughout the bull and bear market. The study suggests that the models of the equilibrium exchange rate exposure must be extended to considering the nonlinear exchange rate exposure, the regime periods of bull and bear market, and the industry types that is sensitive to the currency exposures. The nonlinear dynamic relationship between the exchange rate changes and the Chinese energy stock prices throughout the bull and bear market add to the recent empirical evidences that foreign exchange markets and stock markets are closely correlated.     

A switching ARCH (SWARCH) model of stock market volatility: some evidence from Latin America

We use the Markov regime-switching ARCH (SWARCH) model of Hamilton and Susmel (J Econometrics 64:307–333, 1994) to document the presence of high volatility regimes in six Latin American countries (Argentina, Brazil, Chile, Mexico, Peru, and Venezuela). We found four high volatility episodes, each associated to either a local (the Mexican crisis of 1994, the Brazilian crisis of 1998–1999, the Argentinean crisis of 2001–2002) or a worldwide financial crisis (the Asian financial crisis of 1997). However, we found that the effects of each financial crisis are short-lived and that between 2 and 4 months after each crisis, all markets return to low volatility regimes.

Transaction tax and stock market behavior: evidence from an emerging market

This study examines the impact of a stamp tax rate increase on market behavior, using data from two stock exchanges in China. We find that when the tax rate increases from 0.3 to 0.5% (which implies that the transaction cost increases by about 1/3) trading volume decreases by 1/3. This implies an elasticity of turnover with respect to a stamp tax of −50% and an elasticity of turnover with respect to transaction cost of −100%. The markets’ volatility significantly increases after the increase in the tax rate. Furthermore, the change in the volatility structure indicates that the markets become less efficient in the sense that shocks are less quickly assimilated in the markets.

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Conditional heteroscedasticity with leverage effect in stock returns: Evidence from the Chinese stock market

In recent years the Chinese stock market has experienced an astonishing growth and unprecedented development, but is also viewed as one of the most volatile markets, which has been called by many observers a “casino”. This study intends to examine the presence of heteroskedasticity and the leverage effect in the Chinese stock markets, and to capture the dynamics of conditional correlation between returns of China's stock markets and those of the U.S. in a bivariate VC-MGARCH framework. The results show that the leverage effect is significant in these markets during the sample period in 2000–2013, and the conditional correlation between mainland China's and the U.S. stock markets is quite low and highly volatile. The Chinese stock markets are found to be highly regimes persistent. These findings have important implication for investors seeking opportunity of portfolio diversification.     

Sentiment dynamics and stock returns: the case of the German stock market

We use weekly survey data on short-term and medium-term sentiment of German investors in order to study the causal relationship between investors’ mood and subsequent stock price changes. In contrast to extant literature for other countries, a trivariate vector autoregression for short-run sentiment, medium-run sentiment, and stock index returns allows to reject exogeneity of returns. Depending on the chosen VAR specification, returns are found to either follow a feedback process caused by medium-run sentiment, or returns form a simultaneous systems together with the two sentiment measures. An out-of-sample forecasting experiment on the base of estimated subset VAR models shows significant exploitable linear structure. However, trading experiments do not yield convincing evidence of significant economic gains from the VAR forecasts, and it appears that predictability of returns from sentiment decreases during the recent market gyrations.