The relation between the informational content of implied volatility and arbitrage costs: Evidence from the Oslo Stock Exchange

This study investigates the proposition that volatility of stock returns can be predicted from the volatility implied by options on the Oslo Stock Exchange (OSE), conditional on the ability to perform arbitrage. Insights into the relation between the informational content of implied volatility and arbitrage cost can be distilled from Oslo Stock Exchange data. For Norwegian firms, options and their underlying stock trade on the Oslo Stock Exchange and have an overlapping set of market makers thereby lowering the cost of arbitrage. Other components of arbitrage trading costs, liquidity and dispersion of stock return volatility, vary widely across Norwegian firms. Moreover, restriction on the short selling of stock in Oslo allows further insight into the role of arbitrage costs in determining the informational content of implied volatility. The results yield support for the arbitrage cost hypothesis: the lower the arbitrage cost between the stock and the option, the greater the informational content of implied volatility.     

The effectiveness of the sunshine effect in Taiwan's stock market before and after the 1997 financial crisis

This study constructs a variety of GARCH models with the consideration of the generalized error distribution to analyze the relationship between the cloud cover and stock returns in Taiwan in the whole sample period (1986 to 2007) and in the two sub-sample periods (1986 to 1996 and 1997 to 2007). The data include Taiwan Stock Exchange Capitalization Weighted Stock Index, the primary eight stock sector indices, and the U.S. Dow Jones Industrial Average index to proxy the impact of U.S. stock market on Taiwan's stock market performance. The empirical finding of this study could be used to reconfirm the existence of the so-called sunshine effect. In addition, by comparing the long-run impulse multiplier effects of the cloud cover on the stock return in the two sub-sample periods; this study could examine the transition of the sunshine effect in Taiwan's stock market. The empirical results suggest that cloud cover has a significant negative impact on Taiwan's stock market, especially in the low cloud cover periods. Moreover, the pre-determined distribution of the error term plays an important role on the significance of the sunshine effect. The empirical result shows that most long-run multipliers are negative and the multiplier is more effective in the low cloud cover periods than in the high cloud cover periods.     

Modeling the Taiwan Stock Market and International Linkages

This paper analyzes the Taiwan stock market and examines its price and volatility linkages with those of the United States. In particular, it tests the hypothesis that the short-term volatility and price changes spill over from the developed markets, mainly the United States, to the emerging Taiwan stock market. The model and the test are built upon Engle's ARCH (autoregressive conditional heteroskedasticity) and Engle and Kroner's M-GARCH (multivariate generalized ARCH) models. The paper differs from previous studies on the Taiwan stock market in three respects. First, instead of using daily closing prices, it uses close-to-open and open-to-close returns to avoid the problem of overlapping samples. It carefully models the day-of-the-week effect in daily data to avoid misspecification of the model. Second, to circumvent the generated regressor problem arising from the two-step estimation procedure, it also employs the M-GARCH model where all parameters are estimated simultaneously. Third, the misspecification test is carried out on various kinds of asymmetric ARCH factors. A substantial volatility spillover effect is found from the US stock market to the Taiwan stock market, especially for the model using close-to-open returns. There is also evidence supporting a spillover effect in price changes. The findings can be explained by the recent gradual opening of the Taiwan stock market to foreign investors.     

Nonlinearities in emerging stock markets: evidence from Europe's two largest emerging markets

Recent developments in time series analysis allow proper modelling of nonlinearities in economic and financial variables. A growing body of research was dedicated to investigation of potential nonlinearities in conditional mean of many economic and financial variables, mainly concentrating in developed economies. However, nonlinearities in financial variables in developing economies have not been fully examined yet. In this article we investigate potential nonlinearity and cyclical behaviour of stock returns in Europe's two largest emerging stock markets, mainly in the Greek and Turkish stock markets. Specifically, we use STAR family models, which allow to model nonlinearities in the conditional mean, for modelling monthly returns on stock exchange indices of the Athens Stock Exchange and Istanbul Stock Exchange. Although we find no nonlinearity in conditional variance, we do find strong evidence in favour of nonlinear adjustment of stock returns. It is found that allowing for nonlinearity in conditional mean results in a superior model and provides good out-of-sample forecasts, which contradicts to efficient market hypothesis.     

Option-implied preferences adjustments, density forecasts, and the equity risk premium

The main objective of this paper is to analyse the value of information contained in prices of options on the IBEX 35 index at the Spanish Stock Exchange Market. The forward looking information is extracted using implied risk-neutral density functions estimated by a mixture of two-lognormals and several alternative risk adjustments. Our results show that, between October 1996 and March 2000, we can reject the hypothesis that the risk-neutral densities provide accurate predictions of the distributions of future realisations of the IBEX 35 index at 4- and 8-week horizons. When forecasting through risk-adjusted densities the performance of this period is statistically improved and we no longer reject that hypothesis. We show that risk adjustments based on a power specification for the stochastic discount factor—which is the approach used so far in the literature that derives the objective density function from option prices- generates an excessive volatility of risk premia. We use alternative risk adjustments and find that the forecasting performance of the distribution improves slightly in some cases when risk aversion is allowed to be time-varying. Finally, from October 1996 to December 2004, the ex-ante risk premium perceived by investors and that are embedded in option prices is between 12 and 18% higher than the premium required to compensate the same investors for the realised volatility in stock market returns.      

Co-movement in Stock Prices in Emerging Economies: The Case of the Caricom Region

The Grand Anse Declaration of 1989 recognised the need for financial integration within the emerging economies that comprise the CARICOM region, as a way of furthering the wider process of economic integration and, indeed, economic development in that region. Using co-movement as a measure of financial integration, this paper investigates the co-movement in stock prices among the Barbados, the Jamaica and the Trinidad and Tobago Stock Exchanges, the three major exchanges within the CARICOM region. It also examines how integrated these exchanges are with the New York Stock Exchange. The GARCH-Copula methodology and, to a lesser extent, estimated correlation coefficients, are used to attain this objective. There appears to be co-movement in stock prices and returns within the CARICOM stock markets and significant dependence structures between the returns of the three CARICOM stock markets. However, there is considerably less evidence of integration between the CARICOM markets and the New York Stock Exchange.     

Estimating time-varying variances and covariances via nearest neighbour multivariate predictions: applications to the NYSE and the Madrid Stock Exchange Index

In this article, we present a technique to obtain the time-varying covariance matrix for several time series for nearest neighbour predictors. To illustrate the use of this technique, we analyse the time-varying variances and correlations between the daily returns on two equity stock market indexes, the New York Stock Exchange and the Madrid Stock Exchange Index.     

Time-varying relationship of news sentiment,implied volatility and stock returns

I examine the relationship between aggregate news sentiment, S&P 500 index (SPX) returns, and changes in the implied volatility index (VIX). I find a significant negative contemporaneous relationship between changes in VIX and both news sentiment and stock returns. This relationship is asymmetric whereby changes in VIX are larger following negative news and/or stock market declines. Vector autoregression (VAR) analysis of the dynamics and cross-dependencies between variables reveals a strong positive relationship between previous and current period changes in implied volatility and stock returns, while current period and lagged news sentiment has a significant positive (negative) relationship with stock returns (changes in VIX). I develop a simple trading strategy whereby high (low) levels of implied volatility signal attractive opportunities to take short (long) positions in the underlying index, while extremely negative (positive) news sentiment signals opportunities to enter short (long) index positions. The investor fear gauge (VIX) appears to perform better than news sentiment measures in forecasting future returns.     

Return and volatility spillovers effects: Evaluating the impact of Shanghai-Hong Kong Stock Connect

This study investigates the impact of the recently introduced Shanghai-Hong Kong Stock Connect. Using high frequency data and dynamic forecasting techniques, we find that the new Stock Connect does contribute to the increasing importance of the Chinese mainland stock market and economic activity. A weak and unstable cointegration relationship is found after this event. Additionally, the Stock Connect has also increased the conditional variance of both stock markets. We observe a leading role of the Shanghai stock market to the Hong Kong stock market in terms of both mean and volatility spillover effects after the Stock Connect. Our study indicates that the opening up of stock markets in China could enhance the leading power, influence the risk level and improve the market efficiency of the Chinese mainland stock market, since the volatility spillover effect from Shanghai to Hong Kong is strengthened. Besides, our results have important policy implications, especially on how policy makers should deal with the increased market interconnectedness and for portfolio managers in choosing potential hedging instruments. The success of Shanghai-Hong Kong Stock Connect provides valuable operational experience for the forthcoming Shenzhen-Hong Kong Stock Connect which could further improve the market efficiency in China.     

动量和反转投资策略在我国股市中的实证分析

本文采用沪深两市1995年前上市的股票作为样本,发现我国股市中也存在明显的动量和反转盈利,且两种效应的强弱与大盘走势相关,当市场为牛市特征时,动量效应明显强于反转效应;当市场为熊市特征时,则反之.经典的CAPM模型无法解释动量和反转盈利的来源,检验表明投资者对不同类型信息的不同反应方式,可以很好解释我国股市中的动量和反转盈利,利用上述检验结果还可以解释我国股市中许多有趣的特征.     

Overflow effect of credit rating announcements on stock exchange based on event study

This study is aimed to identify the impact of credit rating announcements on the stock returns in stock markets and for this purpose, four different sectors of Pakistan stock exchange were selected and from each of these four sectors, different business organizations were selected, i.e. total 32 business organizations were selected. The credit rating announcement data were collected for these 32 business organizations belonging to four different sectors. Totally 101 credit rating announcements were selected and the time period for which the credit rating warnings were selected include last three years period, i.e. from 2014 to 2016. The collected data were analysed by calculating abnormal returns for each of the selected security and average abnormal returns, and cumulative average abnormal returns were calculated for four different sectors. Event study methodology was applied, and t-test and t-stats value were calculated and results were analysed on the basis of t-statistics. The results of analysis identified that credit rating announcements have a significant impact on stock prices and investors and other market participants are earning abnormal returns during two-day period after the announcements are made. In addition, these abnormal returns were either negative or positive, depending upon the nature of credit ratings announced. If the credit rating announced was upgraded, investors enjoyed positive abnormal returns while in case when credit rating announcements were downgraded, then investors bear negative abnormal returns. Finally, the findings of the study identified the applicability of random walk hypothesis on the Pakistan Stock Exchange and Pakistan Stock Exchange confirms the efficient market hypothesis with its semi-strong form of efficiency.     

An analysis of the spillover effects of exchange-traded funds

This article used the Generalized Autoregressive Conditional Heteroscedasticity-Autoregressive Moving Average (GARCH-ARMA) and the exponentially Generalized Autoregressive Conditional Heteroscedasticity-Autoregressive Moving Average (EGARCH-ARMA) models to study the impact of the spillover and the leverage effects on returns and volatilities of stock index and Exchange Trade Fund (ETF) for developed and emerging markets. Previous unexpected returns for developed and emerging markets which have an opposite influence pattern on ETFs’ returns were identified. The spillover effects from returns are excellent for Hong Kong, followed by Singapore. Meanwhile, Taiwan's stock index return was recorded to have a strong negative impact on ETF return. Notably, this article shows that the spillover effects on stock index and ETF volatilities existed with bilateral influences. Despite a strong positive asymmetric volatility effect in Korea's ETF market, the leverage effect appears to play important roles in the explanation of both stock index and ETF returns.     

Portfolio performance with controlled variables in the Singapore Stock Market

Recently, many stock return ‘anomalies’ have been identified. This leads to increasing agreement among researchers that these anomalies are relevant to enhancing investment performance. This study examines the existence of stock return anomalies on the Stock Exchange of Singapore in the period 1979–87, using a behavioural approach. The results reveal that the impact of anomalies on stock returns is unstable, with the direction of the impact determined by the strength of the stock market. This phenomenon and other observed anomalies may be partially explained by investors' psychology.     

Structural breaks and GARCH models of stock return volatility: The case of South Africa

This paper investigates the empirical relevance of structural breaks in forecasting stock return volatility using both in-sample and out-of-sample tests applied to daily returns of the Johannesburg Stock Exchange (JSE) All Share Index from 07/02/1995 to 08/25/2010. We find evidence of structural breaks in the unconditional variance of the stock returns series over the period, with high levels of persistence and variability in the parameter estimates of the GARCH(1,1) model across the sub-samples defined by the structural breaks. This indicates that structural breaks are empirically relevant to stock return volatility in South Africa. However, based on the out-of-sample forecasting exercise, we find that even though there structural breaks in the volatility, there are no statistical gains from using competing models that explicitly accounts for structural breaks, relative to a GARCH(1,1) model with expanding window. This could be because of the fact that the two identified structural breaks occurred in our out-of-sample, and recursive estimation of the GARCH(1,1) model is perhaps sufficient to account for the effect of the breaks on the parameter estimates. Finally, we highlight that, given the point of the breaks, perhaps what seems more important in South Africa, is accounting for leverage effects, especially in terms of long-horizon forecasting of stock return volatility.     

Asset prices and economic fluctuations: The implications of stochastic volatility

This paper investigates whether the multi-factor stochastic volatility of stock returns is related to economic fluctuations and affects asset prices. We address these issues in a dynamic Fama-French three-factor volatility model framework. Consistent with the ICAPM with stochastic volatility (Campbell et al., 2017), we find that the conditional volatility of the size and value factors is significantly related to economic uncertainty. These volatilities are also significant pricing factors. The out-of-sample forecasting analysis further reveals that the conditional volatility can predict stock returns and deliver economic gain in asset allocation. Our analysis sharpens the understanding on the link between the stock market and economic fundamentals.     

COMMON STOCHASTIC TRENDS AMONG THE CYPRUS STOCK EXCHANGE AND THE ASE,LSE AND NYSE

Common stochastic trends among major international stock price indices have been an intensively analysed issue mainly as a result of the 1987 stock market crash and the need for policy coordination in financial markets. This paper investigates the existence of common stochastic trends among an emerging equity market, the Cyprus Stock Exchange, and three mature equity markets, namely the Athens Stock Exchange (ASE), the London Stock Exchange (LSE) and the New York Stock Exchange (NYSE).     

Asymmetric Linkages between BRICS Stock Returns and Country Risk Ratings: Evidence from Dynamic Panel Threshold Models

This study investigates the asymmetric linkages between the five BRICS (Brazil, Russia, India, China and South Africa) countries’ stock markets and three country risk ratings (financial, economic and political risk) in the presence of major global economic and financial factors. Using the dynamic panel threshold models, we find evidence of asymmetry in most cases. However, the significance and the signs of the effects of these risk ratings on the BRICS market returns differ across the lower and upper regimes. Furthermore, improvements in the global stock, West Texas Intermediate (WTI) and gold markets enhance the BRICS stock market performance. Increases in implied volatility indices lead to drops in the BRICS markets.     

Are Oil Price News Headlines Statistically and Economically Significant for Investors?

While much has been written about the effects of oil price on stock returns, surprisingly nothing is known about the effect of oil price news on stock returns. This article is a response to this research gap. For a large number of stocks on the New York Stock Exchange, the authors find that while oil price news does predict market returns it only predicts returns of some sectors and not all. They find that sorting stocks based on oil price news generates a significant return differential in the cross-section, which holds consistently across a range of models allowing for the well-known risk factors. Their findings suggest that information contained in oil price news affects stock returns.     

EU Emission Allowances and the stock market: Evidence from the electricity industry

This paper constitutes - to our best knowledge - the first econometric analysis on stock market effects of the EU Emission Trading Scheme (EU ETS). Our results suggest that EU Emission Allowance (EUA) price developments matter to the stock performance of electricity firms: EUA price changes and stock returns of the most important European electricity corporations are shown to be positively related. This effect does not work asymmetrically, so that stock markets do not seem to react differently to EUA appreciations in comparison to depreciations. The carbon market effect is shown to be both time- and country-specific: It is particularly strong for the period of EUA market shock in early 2006, and differs with respect to the countries where the electricity corporations analysed are headquartered. Stock market reactions to EUA volatility could not be shown.     

石化权证在GARCH模型下的实证检验

股票价格的波动率特征是股票衍生品价格的决定性因素。Black&Scholes假设股票价格服从几何布朗运动,其重要的假设条件是波动率为一个常数。但是,越来越多的实证研究结果表明,股票收益率存在显著的尖峰厚尾现象,其波动率存在明显的时变性特征。因此,放宽波动率恒定条件,并且研究股票波动率的变动特征,对认购权证的正确定价具有重要意义。