The information content of implied volatility in developed versus developing FX markets

This article predicts the daily movement of monthly foreign exchange (FX) rate volatility using a linear combination of a time-series model and implied volatilities from options. The focus is on analysing the FX volatilities in three developing economies (the Brazilian real (BRL), the Indian rupee (INR) and the Russian ruble (RUB)) against the US dollar (USD). The empirical exercise utilizes two time-series models, mixed data sampling (MIDAS) and GARCH. The analysis indicates that for both developed and developing economies the predictive power of MIDAS and that of GARCH is comparable. Further on in this article, we will ascertain whether the relationship between realized and implied volatility is fundamentally different in the case of developing economies from that among developed economies. Thus, we compare the pairs USD/BRL, USD/INR and USD/RUB against EURO/USD and USD/Japanese yen to determine the information content and predictive power of implied volatilities. Plots of the MIDAS coefficients show that the volatility is more persistent in developing economies than in developed economies.     

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.     

Calibration of implied volatility for the exchange rate for the Chinese Yuan from its derivatives

Revised implied volatility curves and surfaces for the Chinese Yuan (CNY) exchange rate are obtained from market quotations for CNY non-deliverable options by solving an inverse problem of foreign exchange option pricing, which is calculated using a regularization approach in an optimal control framework. To take account of the market expectation for the CNY exchange rate, a stochastic adjusted factor is applied that follows a Vasicek model with parameters fitted from market quotations for CNY non-deliverable forwards. A well-posed numerical scheme is implemented.     

A new factor to explain implied volatility smirk

In this article, we find empirical evidence of a new smirk factor, obtained from the jump structure of the risk neutral distribution of the underlying Lévy process. As an application we show how to price a barrier style contract.     

Smiling under stochastic volatility

This paper studies the behavior of the implied volatility function (smile) when the true distribution of the underlying asset is consistent with the stochastic volatility model proposed by Heston (1993). The main result of the paper is to extend previous results applicable to the smile as a whole to alternative degrees of moneyness. The conditions under which the implied volatility function changes whenever there is a change in the parameters associated with Hestons stochastic volatility model for a given degree of moneyness are given.JEL Classification: G12, G13Mathematical assistance provided by José Alcalde (Universidad de Alicante) is much appreciated, and we have also benefited from discussions with Eva Ferreira (Universidad del País Vasco) and Javier Fernández Navas (Instituto de Empresa). We also thank José M. Campa (IESE) and two anonymous referees, whose suggestions have helped us improve this paper substantially. Gonzalo Rubio and Ángel León acknowledge the financial support provided by Ministerio de Ciencia y Tecnología grants BEC2001-0636 and BEC2002-03797 respectively. Ángel León also acknowledges Generalitat Valenciana grant CTIDIA/2002/103. The contents of this paper are the sole responsibility of the authors.     

Investors’ fear and herding in the stock market

ABSTRACT

In this article, we examine herding in three developed stock markets testing for the impact of investors’ ‘fear’ on herding estimations. To this end, we employ daily data of all listed stocks from USA, UK and Germany from January 2004 to July 2014. We examine herd behaviour applying the cross-sectional dispersion approach. Moreover, we investigate the asymmetric herding behaviour under different market states and sub-periods. The stock markets under examination provide comparable implied volatility indices which are used as a proxy for fear. As a result, apart from the standard herding estimations within and across markets, we also augment the benchmark model with the fear indicator. Our empirical results document the statistically significant impact of fear on herding estimations. Moreover, there is evidence of cross market herding as well as evidence of herding in the UK during specific sub-periods.     

Implied correlation indices and volatility forecasting

Implied volatility indices are an important measure for ‘market fear’ and well-known in academia and practice. Correlation is still paid less attention even though the CBOE started to calculate implied correlation indices for the S&P500 in 2009. However, the literature especially on cross-country dependencies and applications is still quite thin. We are closing this gap by constructing an implied correlation index for the DAX and taking a deeper look at the (intercontinental) relationship between equity, volatility and correlation indices. Additionally, we show that implied correlation could improve implied volatility forecasting.     

Early exercise European option and early termination American option pricing models

The maximum relative error between continuous-time American option pricing model and binomial tree model is very small. In order to improve the European and American options in trade course, the thesis tried to build early exercise European option and early termination American option pricing models. Firstly, the authors reviewed the characteristics of American option and European option, then there was compares between them. Base on continuous-time American option pricing model, this research analyzed the value of these options.     

Option Pricing Based on Alternative Jump Size Distributions

It is well known that volatility smirks and heavy-tailed asset return distributions are two violations of the Black-Scholes model. This paper investigates the role of jump size distribution played in explaining these two abnormalities. We consider a jump-diffusion model with Laplace jump size distribution, in comparison to the conventional normal distribution. In addition, our analysis is built upon a pure exchange economy, in which the representative agent’s risk preference shows a fanning characteristic. We find that, when a fanning effect is present, Laplace model produces a more remarkable leptokurtic pattern of the risk-neutral distribution implied by options, as well as generating more pronounced volatility smirks than the normal model.     

Forecasting stock market volatility and information content of implied volatility index

This study investigates the incremental information content of implied volatility index relative to the GARCH family models in forecasting volatility of the three Asia-Pacific stock markets, namely India, Australia and Hong Kong. To examine the in-sample information content, the conditional variance equations of GARCH family models are augmented by incorporating implied volatility index as an explanatory variable. The return-based realized variance and the range-based realized variance constructed from 5-min data are used as proxy for latent volatility. To assess the out-of-sample forecast performance, we generate one-day-ahead rolling forecasts and employ the Mincer–Zarnowitz regression and encompassing regression. We find that the inclusion of implied volatility index in the conditional variance equation of GARCH family model reduces volatility persistence and improves model fitness. The significant and positive coefficient of implied volatility index in the augmented GARCH family models suggests that it contains relevant information in describing the volatility process. The study finds that volatility index is a biased forecast but possesses relevant information in explaining future realized volatility. The results of encompassing regression suggest that implied volatility index contains additional information relevant for forecasting stock market volatility beyond the information contained in the GARCH family model forecasts.     

The Black–Scholes model as a determinant of the implied volatility smile: A simulation study

The paper represents an initial effort to shed light on the determinants of the implied volatility smile in financial (derivative) markets. It fully details the implications of the institutionalization of the Black–Scholes model in an uncertain world populated by individuals who are bounded by the amount of calculation or accounting which is technically possible. Combining model simulations, empirical analysis, and mathematical derivations, the paper proposes that the determinants of the volatility smile might be related to the behavior of traders. In pricing options, they use the widely accepted Black–Scholes formula with a measure of stock volatility that they derive from their subjective beliefs. Moreover, heterogeneity of traders’ beliefs and the way traders update their expectations have nontrivial effects, both on equilibrium prices and on the emergence of the implied volatility smile.     

中国股市收益、收益波动与投资者情绪

本文从我国股市的现实情况出发 ,构造理论模型证明 :投资者接受价格信号时表现出来的情绪是影响均衡价格的系统性因子。这一结论得到实际数据的支持 ,实证发现投资者情绪的变化不仅显著地影响沪深两市收益 ,而且显著地反向修正沪深两市收益波动 ,并通过风险奖励影响收益。研究结果表明 ,沪深两市不仅具有相同的投资者行为和风险收益特征 ,而且均未达到弱式有效 ,机构投资者是可能的噪声交易者风险源。     

期权博弈的分类及其在不完全信息下的均衡策略研究

期权博弈的分类与均衡策略研究是进行期权博弈模型研究,为企业在不同的竞争性投资实践中提供科学决策的基础与根本。首先从实物期权的种类和竞争特性出发对期权博弈进行了分类与界定。然后,在不完全信息条件下,重点研究了占优型实物期权博弈均衡策略。无论是在高成本或低成本类型下,占优型企业均会以低成本的身份选择最佳投资时机和最佳垄断产量进入市场生产、成为市场的领导者;在观察到领导者行动策略的基础上,追随者按实物期权方法的投资决策基本规则确定其进入市场的最佳投资时机;随后,领导者与追随者按照精炼贝耶斯纳什均衡产量进行生产,共同获得市场均衡收益。     

Investing in mutual funds: the determinants of implied and actual net cash flows

Estimating the fund investors’ demand plays an important role in the mutual fund management. In this line, mutual fund demand can be measured as the total net cash flows experienced by the fund during a period. Due to a lack of the data for inflows and outflows in some countries and databases, many authors estimate the net cash flows using fund size and return information. This rough measure, although being a good approximation, implicitly assumes an error in its calculation. For a sample of 2985 US open-end funds, we find evidence that estimating this implied fund flows, the error generated is higher for smaller funds, funds with higher returns, and for those experiencing higher levels of inflows or outflows. This lack of precision leads to a distortion in the estimation of the effect of some determinants on the mutual fund demand, especially when longer periods are considered when constructing the net cash flows.     

股票期权激励与高管风险承担的关系——考虑媒体关注的调节作用

依据行权条件和行权有效期将股票期权激励方案分为"高标准型"和"低标准型",利用2006—2013年中国沪深两市实施股票期权激励的上市公司的数据,实证考察了两类样本组中股票期权激励与高管风险承担的关系,以及媒体关注对两者间关系的调节作用。研究发现:"高标准型"股票期权激励与高管风险承担之间存在呈倒U形关系;"低标准型"股票期权激励与高管风险承担之间存在负相关关系;媒体关注度越高,"高标准型"组中两者倒U关系的拐点越滞后,同时"低标准型"组中两者的负相关关系越弱。     

Variability of realized stock returns and trading volume

Using monthly data for 2005–2014 time period, this article documents the relationship between lagged stock returns and trading volume. We show that the dispersion of stock returns in a market portfolio positively affects future trading volume. We also show that extreme negative returns lead to high future trading volume while extreme positive returns have little effect on future trading. Dividing our sample into several sub-samples based on the Standard Industrial Classification (SIC) divisions leads to similar results for most of the SIC divisions.     

含权债券定价的统一框架及其数值分析

本文从理论上推导了一般债券定价的偏微分方程,详细分析了包含欧式和美式看涨和看跌期权的4类债券,并给出了4类含权债券定价的边界条件。利用隐性差分法数值求解了偏微分方程,针对4类期权对不同利率参数的敏感性进行了分析。     

Volatility spillovers across daytime and overnight information between China and world equity markets

This article explores the transmission of daytime and overnight information in terms of returns and volatility between Chinese and Asian, European and North American main stock markets. We propose a bivariate analysis with China as benchmark. By testing the constancy of the conditional correlations, we use an extended constant or dynamic conditional correlation GARCH model. The empirical findings show that across the daytime information transmissions, the relationships between China and Asian markets are closer than China and non-Asian markets, whereas through the overnight information transmissions these relationships are inverse. The analysis provides, before the crisis, that the overnight volatility spillover effects are from China to the United States and the United Kingdom. During the crisis, China affects the United Kingdom in terms of daytime volatility spillovers, whereas in terms of overnight volatility spillovers China affects the United States and is influenced by Japan. After the crisis, daytime volatility spillovers are from Taiwan to China, whereas the overnight volatility spillover effects are from China to the United States and the United Kingdom.     

Stock return predictability: the role of inflation and threshold dynamics

This paper argues that the nature of stock return predictability varies with the level of inflation. We contend that the nature of relations between economic variables and returns differs according to the level of inflation, due to different economic risk implications. An increase in low level inflation may signal improving economic conditions and lower expected returns, while the opposite is true with an equal rise in high level inflation. Linear estimation provides contradictory coefficient values, which we argue arises from mixing coefficient values across regimes. We test for and estimate threshold models with inflation and the term structure as the threshold variable. These models reveal a change in either the sign or magnitude of the parameter values across the regimes such that the relation between stock returns and economic variables is not constant. Measures of in-sample fit and a forecast exercise support the threshold models. They produce a higher adjusted R², lower MAE and RMSE and higher trading related measures. These results help explain the lack of consistent empirical evidence in favour of stock return predictability and should be of interest to those engaged in stock market modelling as well as trading and portfolio management.     

Optimal sale across venues and auctions with a buy-now option

We characterize the optimal selling mechanism for a seller who faces demand demarcated by a high and a low end and who can access an (online) auction site (by paying an access cost) in addition to using his own store that can be used as a posted price selling venue. We first solve for the optimal mechanism of a direct revelation game in which there is no venue-restriction constraint. We find that the direct optimal mechanism must necessarily incorporate a certain kind of pooling. We then show that even with the venue constraint, the seller can use a two stage indirect mechanism that implements the allocation rule from the optimal direct mechanism, and uses the venues in an optimal fashion. The first stage of the indirect mechanism is a posted price at the store. If the object is not sold, we move to stage two, which involves an auction at the auction site. A feature of this auction is a buy-now option which is essential for implementing the pooling feature of the optimal direct mechanism. We also show that the buy-now option in the optimal mechanism is of a “temporary” variety, and that a “permanent” buy-now option, in contrast, cannot implement the optimal mechanism. Auctions with a temporary buy-now option are in widespread use on eBay. We thank the Associate Editor, George Deltas, for his insightful comments. We also thank seminar participants at the University of Basel and the SAET conference 2007.