Modelling International Price Relationships and Interdependencies Between the Stock Index and Stock Index Futures Markets of Three EU Countries: A Multivariate Analysis

This paper addresses the important relationship between stock index and stock index futures markets in an international context. By simply examining the spot‐futures relationship within a single country as most of the extant literature does and thus ignoring possible market interdependencies between countries, the dynamics of price adjustments may be misspecified and thus findings misleading. The main contribution of the paper is to improve our understanding of the pricing relationship between spot and futures markets in the light of international market interdependencies. Using a multivariate VAR‐EGARCH methodology, the paper investigates stock index and stock index futures market interdependence, that is lead‐lag relationships and volatility interactions between the stock and futures markets of three main European countries, namely France, Germany and the UK. In addition, the paper explicitly accounts for potential asymmetries that may exist in the volatility transmission mechanism between these markets. The main conclusions of the paper imply that investors need to account for market interactions across countries to fully and correctly exploit the potential for hedging and diversification.     

Return predictability in African stock markets

This paper models weekly index returns adjusted for thin trading as a nonlinear autoregressive process with conditional heteroscedasticity to investigate the weak-form pricing efficiency of 11 African stock markets. Specifically, the use of the EGARCH-M model allows us to capture how conditional volatility affects the pricing process without imposing undue restrictions on the parameters of the conditional variance equation. On the basis of such a robust model, we are able to reject the evidence in prior studies that the Nigerian stock market is weak-form efficient. On the other hand, we confirm extant results that the markets in Egypt, Kenya, and Zimbabwe are efficient while that of South Africa is not weak-form efficient. We also generate new results, which point to the efficiency of the stock markets in Mauritius and Morocco, while the markets in Botswana, Ghana, Ivory Coast, and Swaziland are not consistent with weak-form efficiency.     

Factor Models for Option Pricing

Options on stocks are priced using information on index options and viewing stocks in a factor model as indirectly holding index risk. The method is particularly suited to developing quotations on stock options when these markets are relatively illiquid and one has a liquid index options market to judge the index risk. The pricing strategy is illustrated on IBM and Sony options viewed as holding SPX and Nikkei risk respectively.     

Is the information obtained from European options on equally weighted baskets enough to determine the prices of exotic derivatives such as worst-of options?

In recent years there has been a remarkable growth of multi-asset options. These options exhibit sensitivity to the volatility of the underlying assets, as well as to their correlations. The call versus call is a product commonly used to trade correlation within the inter-dealer broker markets. The buyer of correlation buys a European call on the equally weighted basket option and sells a weighted average of European calls on each asset. In this case, the following important question arises: Is the information provided by equally weighted basket options enough to price other European multi-asset exotic derivatives such as worst-of or outperformance options? This article investigates this issue under a stochastic correlation framework. Importantly, this article shows that, when pricing multi-asset exotic derivatives, matching the prices of European equally weighted basket options, quoted in the market, does not guaranty the absence of model risk even in the case where the exotic payoff is observed only at maturity.     

Informational linkage and price discovery between China's futures and spot markets: Evidence from the US–China trade dispute

This study examines the effects of the US–China trade dispute on the informational linkages and price discovery between China's futures and spot markets. Using the daily price data of four assets representing the real and financial sectors in China during 2016–2019, empirical findings suggest that the futures–spot correlations for the stock index, copper, and corn markets have increased significantly during the trade dispute. In contrast, sharp declines in the dynamic correlations between gold futures and spot markets, as gold is a safe haven asset, are observed during the event window. During uncertainty disturbance (i.e., the trade dispute), the futures–spot cointegrated relationships in the gold and corn markets are found to adjust more quickly and efficiently, whereas the correction speeds of the market deviations for the stock index and copper market are moderately slower. With the intensive integration of market expectations with uncertainty shocks, the economic shocks of trade disputes tend to remarkably improve the pricing efficiency of China's futures markets, except for the gold futures market. China's spot markets, however, seem to be more sensitive to the noise trades and information disturbances arising from the trade dispute.     

A theory of trading in stock index futures

It is demonstrated that markets in stock index futures or, moregenerally, in baskets of securities, provide a preferred tradingmedium for uniformed liquidity traders who wish to trade portfolios,because adverse selection costs are typically lower in thesemarkets than in markets for individual securities. Thus, anexplanation is provided for the immense liquidity and popularityof markets in stock index futures. Implications are also developedfor the effect of the introduction of a basket on market liquidityand the informativeness and variability of component securityprices, and for the price relationship between the basket andits underlying portfolio.     

The multivariate Variance Gamma model: basket option pricing and calibration

In this paper, we propose a methodology for pricing basket options in the multivariate Variance Gamma model introduced in Luciano and Schoutens [Quant. Finance 6(5), 385–402]. The stock prices composing the basket are modelled by time-changed geometric Brownian motions with a common Gamma subordinator. Using the additivity property of comonotonic stop-loss premiums together with Gauss-Laguerre polynomials, we express the basket option price as a linear combination of Black & Scholes prices. Furthermore, our new basket option pricing formula enables us to calibrate the multivariate VG model in a fast way. As an illustration, we show that even in the constrained situation where the pairwise correlations between the Brownian motions are assumed to be equal, the multivariate VG model can closely match the observed Dow Jones index options.     

Transactions data tests of efficiency of the Chicago board options exchange

This paper performs lower boundary condition tests based on rational pricing of call options and an implied standard deviation test based on the bid/ask prices of options. These efficiency tests attempt to closely approximate conditions in the option markets to avoid the pitfalls indicated by Phillips and Smith (1980). The tests use transactions data and account for the effects of stock and option bid/ask prices, simultaneity of stock and option prices, depth of market, execution lag and transaction costs. The small and relatively infrequent profits due to market mispricing disappear in the lower boundary tests when transaction costs are taken into account. Frequent violations of the tighter boundary conditions in the implied standard deviation test are reported, but the estimated profits cannot be unambiguously attributed to option market inefficiency.     

Regional integration of the East Asian stock markets: An empirical assessment

The aim of this paper is to study the dynamics of regional financial integration in East Asia over the 1990:01–2012:08 period. To this end, we use the international capital asset pricing model (ICAPM) to assess the evolution of financial market integration through time and evaluate their risk premia. We also construct an Asian currency basket in order to obtain a reference currency in this area. Our empirical analysis is based on the multivariate GARCH-DCC approach with time-varying correlations. Our results show that the East Asian stock markets were partially segmented (except for Japan) within their region until approximately 2008. However, the last years are characterized by an upward trend in the regional integration of stock markets. Our findings also show that the risk premium related to regional stock markets is significant for all countries.     

An analysis of option pricing under systematic consumption risk using GARCH

An issue in the pricing of contingent claims is whether to account for consumption risk. This is relevant for contingent claims on stock indices, such as the FTSE 100 share price index, as investor’s desire for smooth consumption is often used to explain risk premiums on stock market portfolios, but is not used to explain risk premiums on contingent claims themselves. This paper addresses this fundamental question by allowing for consumption in an economy to be correlated with returns. Daily data on the FTSE 100 share price index are used to compare three option pricing models: the Black–Scholes option pricing model, a GARCH (1, 1) model priced under a risk-neutral framework, and a GARCH (1, 1) model priced under systematic consumption risk. The findings are that accounting for systematic consumption risk only provides improved accuracy for in-the-money call options. When the correlation between consumption and returns increases, the model that accounts for consumption risk will produce lower call option prices than observed prices for in-the-money call options. These results combined imply that the potential consumption-related premium in the market for contingent claims is constant in the case of FTSE 100 index options.     

全球股指期货与期权市场的发展动向及启示

本文通过对近年来全球股指期货及期权场内交易发展态势及动向分析,指出全球股指期货及期权呈现出交易量稳居各类产品之首、交易高度集中于几家交易所的几种产品、中国概念股指备受关注、创新步伐不断加快等四大趋势,启示我们适时推出股指期货,研究股指期权,不但可以拓展期货市场发展空间,推动境内资本市场的健康发展,建立完善的股指市场体系,而且是股票类衍生品创新的基础。     

Does herding behavior exist in Chinese stock markets?

This paper examines the presence of herd formation in Chinese markets using both individual firm- and sector-level data. We analyze the behavior of return dispersions during periods of unusually large upward and downward changes in the market index. We also distinguish between the Shanghai and Shenzhen stock exchanges at the sector-level. Our findings indicate that herd formation does not exist in Chinese markets. We find that equity return dispersions are significantly higher during periods of large changes in the aggregate market index. However, comparing return dispersions for upside and downside movements of the market, we observe that return dispersions during extreme downside movements of the market are much lower than those for upside movements, indicating that stock returns behave more similarly during down markets. The findings support rational asset pricing models and market efficiency. Policy implications of the results for policymakers are discussed.     

股指期权对股指期货的促进作用:来自韩国的证据

本文结合解析韩国KOSPI200期权对于KOSPI200期货市场的影响,论证股指期权市场对股指期货市场在提高流动性和培育机构投资者方面的显著作用。借鉴韩国股指衍生品市场发展经验,笔者认为在沪深300股指期货平稳运行之后,要选择时机及时推出股指期权,这样可以保证良好的流动性。为此,应当加快制定股指衍生品市场体系的发展战略。     

The predictive power of the implied volatility of options traded OTC and on exchanges

This paper investigates the efficiency of stock index options traded over-the-counter (OTC) and on the exchanges in Hong Kong and Japan. Our findings suggest that implied volatility is superior to either historical volatility or a GARCH-type volatility forecast in predicting future volatility in both the OTC and exchange markets. This paper is also one of the first to compare the predictive power of the implied volatility of stock index options traded OTC to that of exchange-traded stock index options. Our evidence suggests that the OTC market is more efficient than the exchanges in Japan, but that the opposite is true in Hong Kong.     

Informed trading under different market conditions and moneyness: Evidence from TXO options

We examine the informational role of options across exercise prices under different market conditions. We analyze the influence of options' leverage effect, and market cycles on the cause–effect relation between stock and options markets based on an emerging options market—the Taiwan stock index options market. When aggregating market data irrespective of market cycles and options moneyness, we find that the equity market leads the options market. However, as we control options' moneyness and market cycles, we find that out-of-the-money options lead the stock market by up to 90 min with more pronounced results in downtrends and periods of political tension. Our findings suggest that the informational role of options is interacted with leverage effect and market conditions.     

Futures Options and the Volatility of Futures Prices

Assuming nonstochastic interest rates, European futures options are shown to be European options written on a particular asset referred to as a futures bond. Consequently, standard option pricing results may be invoked and standard option pricing techniques may be employed in the case of European futures options. Additional arbitrage restrictions on American futures options are derived. The efficiency of a number of futures option markets is examined. Assuming that at-the-money American futures options are priced accurately by Black's European futures option pricing model, the relationship between market participants' ex ante assessment of futures price volatility and the term to maturity of the underlying futures contract is also investigated empirically.     

Short-selling bans and institutional investors' herding behaviour: Evidence from the global financial crisis

The literature on short-selling restrictions focusses mainly on a ban's impact on market efficiency, liquidity and overpricing. Surprisingly, little is known about the effects of short-sale constraints on herd behaviour. Since institutional investors have come to dominate mature stock markets and rely extensively on short sales, constraining these traders may influence the asset pricing process. We investigate six stock markets that faced bans during the recent global financial crisis. Our empirical evidence shows that short-selling restrictions exhibit either no influence on herding formation or induce adverse herding. This implies a higher dispersion of returns around the market compared to rational asset pricing, which can be interpreted as an increase in uncertainty among stock market investors.     

An investor sentiment barometer — Greek Implied Volatility Index (GRIV)

In this paper, we propose a new measure of Greek equity market volatility based on the prices of FTSE/ATHEX-20 index options. Greek Implied Volatility Index is calculated using the model-free methodology that involves option prices summations and is independent from the Black and Scholes pricing formula. The specific method is applied for the first time in a peripheral and illiquid market as the Athens Exchange.The empirical findings of this paper show that the proposed volatility index includes information about future realized volatility beyond that contained in past volatility. In addition, our analysis indicates that there is a statistically significant negative and asymmetric contemporaneous relationship between the returns of the implied volatility index and the underlying equity index. Finally, the volatility transmission effects on the Greek stock exchange from two leading markets, namely the New York Stock Exchange and the Deutsche Börse, are tested and documented.     

A dynamic equilibrium model for U-shaped pricing kernels

This paper proposes a dynamic equilibrium model that can provide a unified explanation for the stylized facts observed in stock index markets such as the fat tails of the risk-neutral return distribution relative to the physical distribution, negative expected returns on deep OTM call options and negative realized variance risk premiums. In particular, we focus on the U-shaped pricing kernel against the stock index return, which is closely related to the negative call returns. We assume that the stock index return follows a time-changed Lévy process and that a representative investor has power utility over the aggregate consumption that forms a linear regression of the stock index return and its stochastic activity rate. This model offers a macroeconomic interpretation of the stylized facts from the perspective of the sensitivity of the activity rate and stock index return on aggregate consumption as well as the investor’s risk aversion.     

Informed trading in the options market surrounding data breaches

This study investigated whether there is informed trading that takes advantage of data breach events. By analyzing the transactions in the options market, we conjectured that there are two distinct informed trading patterns: one that begins approximately 4 months prior and another that begins 8–12 months before the corporate data breach announcements. This is supported by evidence of higher trading volume and open interest for put options, a higher put-to-call volume ratio, a higher put-to-call open interest ratio, and lower spreads prior to such announcements. We also examined the stock reactions following data breach announcements and found significantly negative cumulative abnormal returns of −0.35% within one day. Moreover, a cross-sectional analysis showed that put-call ratios have predictive power for stock returns. Finally, additional evidence, such as trading strategies in the stock and options markets, is provided.