Volatility estimation from observed option prices

It is well established that the standard Black-Scholes model does a very poor job in matching the prices of vanilla European options. The implied volatility varies by both time to maturity and by the moneyness of the option. One approach to this problem is to use the market option prices to back out a local volatility function that reproduces the market prices. Since option price observations are only available for a limited set of maturities and strike prices, most algorithms require a smoothing technique to implement this approach. In this paper we modify the implementation of Andersen and Brotherton-Ratcliffe to provide another way of dealing with this issue. Numerical examples indicate that our approach is reasonably successful in reproducing the input prices.     

带Poisson跳的Black-Scholes模型的期权定价

主要讨论欧式期权的定价公式。首先给出一个B-S期权定价公式的简化方法,使具有一般微积分知识的读者就能理解;并假定股票价格过程遵循带Poisson跳的扩散过程,在股票预期收益率、波动率和无风险利率均为时间函数的情况下,得到欧式期权定价公式和买权与卖权之间的平价关系。     

European quanto option pricing in presence of liquidity risk

In this paper, we study the pricing problems of the European quanto options in which the underlying foreign asset is in imperfectly liquid markets. First, we assume that the dynamics of the underlying foreign asset price are affected by market liquidity and propose a liquidity-adjusted quanto model. This allows for the effects of market liquidity on European quanto option pricing. And then we derive the analytical pricing formulas for four different types of European quanto options. Finally, we empirically investigate the pricing performance of our proposed model with a European quanto construction involving the SSE 50 ETF, as the underlying asset, and the CNY/HKD exchange rate. Empirical results demonstrate that the pricing accuracy of the proposed model is markedly superior to that of the Black-Scholes quanto model. In other words, allowing for liquidity risk in the framework of European quanto option pricing can make markedly improvements in fitting the real market data. Particularly, the improvement rate is high for medium-term and out-of-the-money options. Moreover, these results are robust for different liquidity measures.     

Stock market volatility forecasting: Do we need high-frequency data?

The general consensus in the volatility forecasting literature is that high-frequency volatility models outperform low-frequency volatility models. However, such a conclusion is reached when low-frequency volatility models are estimated from daily returns. Instead, we study this question considering daily, low-frequency volatility estimators based on open, high, low, and close daily prices. Our data sample consists of 18 stock market indices. We find that high-frequency volatility models tend to outperform low-frequency volatility models only for short-term forecasts. As the forecast horizon increases (up to one month), the difference in forecast accuracy becomes statistically indistinguishable for most market indices. To evaluate the practical implications of our results, we study a simple asset allocation problem. The results reveal that asset allocation based on high-frequency volatility model forecasts does not outperform asset allocation based on low-frequency volatility model forecasts.     

Dupire’s formulas in the Piterbarg option pricing model

In this paper we derive an expression for the local volatility of an underlying asset, given the prices of liquid European call options under the Piterbarg framework. The Piterbarg framework is a multi-curve derivative pricing model which extends the well known Black–Scholes–Merton model by relaxing the assumption of a risk-free interest rate, and includes collateral payments. The expressions for the local volatility is a function of the option price surface, and is then transformed to become a function of the implied volatility surface.     

Joint dynamic modeling and option pricing in incomplete derivative-security market

In this study, we evaluate the option prices on two assets under stochastic interest rates when the stochastic process that underlying asset prices follow is depending on a correlated bivariate Markov-modulated geometric Brownian motion model with jump risks. More specifically, we conduct the joint dynamic modeling by identifying two independent compound Poisson processes with the log-normal jump sizes to describe both individual jumps and systematic cojumps. Facilitating the cojumping behavior this way with the time-inhomogeneity of the volatility, option pricing expressions are readily obtainable since the Gerber–Siu’s approach is employed to determine a pricing kernel. The empirical results and numerical illustrations are provided to show the impact of cojumps and stochastic volatilities on option prices.     

基于无套利对冲原理的信用风险期权定价

文章拓展了Klein假设中关于固定违约门槛的假设,构造可变违约门槛,根据无套利对冲原理,通过偏微分方程这种数学工具,推导出含信用风险的欧式脆弱期权价格波动的偏微分方程组和期权定价模型,进而求其显示解,得到类似于Black-Scholes公式的定价公式,该公式的推导过程比使用鞅理论推导更加浅显易懂。     

期权定价模型的离散化矩估计

在本文中,把期权定价模型中的漂移项为一个常数,波动率假定为一个Ornstein-Uhlenbeck过程,在一定的条件下,把模型转变成唯一个双线性自回归EV模型,然后对其中的m(·)函数进行离散化后,通过矩估计的方法估计m(·)函数的系数,从而得到波动率σ的矩估计。     

基于实物期权法的风险投资项目估价方法——一个文献综述

本文理清了实物期权及其在风险投资项目估价中应用的发展脉络,并提出了实物期权在风险投资项目估价应用中需要发展的地方。     

Aggregate volatility expectations and threshold CAPM

We propose a volatility-based capital asset pricing model (V-CAPM) in which asset betas change discretely with respect to changes in investors’ expectations regarding near-term aggregate volatility. Using a novel measure to proxy uncertainty about expected changes in aggregate volatility, i.e. monthly range of the VIX index (RVIX), we find that portfolio betas change significantly when uncertainty about aggregate volatility expectations is beyond a certain threshold level. Due to changes in their market betas, small and value stocks are perceived as riskier than their big and growth counterparts in bad times, when uncertainty about aggregate volatility expectations is high. The proposed model yields a positive and significant market risk premium during periods when investors do not expect significant uncertainty in near-term aggregate volatility. Our findings support a volatility-based time-varying risk explanation.     

News shocks and asset price volatility in general equilibrium

We study equity price volatility in general equilibrium with news shocks about future productivity and monetary policy. As West (1988) shows, in a partial equilibrium present discounted value model, news about the future cash flow reduces asset price volatility. We show that introducing news shocks in a canonical dynamic stochastic general equilibrium model may not reduce asset price volatility under plausible parameter assumptions. This is because, in general equilibrium, the asset cash flow itself may be affected by the introduction of news shocks. In addition, we show that neglecting to account for policy news shocks (e.g., policy announcements) can potentially bias empirical estimates of the impact of monetary policy shocks on asset prices.     

Pricing currency options with scheduled and unscheduled announcement effects on volatility

It is well documented that exchange rate volatility is time-varying and that it can be affected by scheduled events such as money supply announcements and unscheduled ones such as spot market interventions and interest rate changes. This study provides a European event model (E model) for currency call options that explicitly addresses the volatility effects of these two classes of events. Managers who are concerned with hedging in an environment of changing volatility may find the E model useful. The E and modified Black-Scholes (MBS) models have similar average errors in predicting option price changes across event windows and do better than a naive no-change prediction. The E model tends to reduce the underpricing of convex, short-term out-of-the-money options and the mispricing of most classes of convex options.     

Scheduled macroeconomic news announcements and intraday market sentiment

We analyze the effects of scheduled macroeconomic news on intraday and daily market sentiment by comparing sentiment on news announcement dates with that on non-announcement dates. Announcements of macroeconomic indicators change neither intraday nor daily market sentiment. However, the directions of the announced values have asymmetric effects on intraday market sentiment, although they do not affect daily market sentiment. For example, an announcement of an increase in the gross domestic product (GDP) reduces short-term intraday market sentiment, whereas an announcement of a decrease in GDP does not significantly affect intraday market sentiment. We also find that the effect of intraday market sentiment on short-term market returns is greater following announcements of macroeconomic indicators that significantly affect intraday market sentiment.     

Mandated Recognition of Employee Stock Option Expense – The Case of Canada

On December 18, 2003 the Accounting Standards Board of Canada announced that all firms registered in Canada would be required to expense stock options‐based compensation effective January 1, 2004. While a few firms had voluntarily opted to expense stock options prior to this date, the vast majority of firms had not. This study investigates the market reaction to this announcement by listed firms in the Toronto Stock Exchange that continued to disclose option expense rather than report it in the financial statement. We find no average market reaction by our sample firms affected by this mandate around the announcement date, but a significantly negative market reaction during the 5‐day window around the issuance date of the exposure draft. However, in cross‐sectional tests around the mandated expense announcement date, we find a significant negative relationship between the cumulative abnormal returns and the Black–Scholes value (and number) of options outstanding and of options granted the previous year. These results suggest that the magnitude of the market reaction to the mandated expense announcement is related to the firm's usage of options. Our results provide further evidence that stock prices may not fully impound information disclosed in footnotes.     

The European Market Abuse Directive: Has it Worked?

In this paper, we examine whether the Market Abuse Directive (MAD) has been effective in achieving its objectives of deterring the market manipulation activities, increasing the timeliness of information and decreasing the disclosure of inside information to select groups. Our sample consists of firms listed on Frankfurt Stock Exchange. We use stock prices and analysts' forecast‐based proxies to examine the impact and effectiveness of MAD. The analysis based on these two set of proxies provides evidence that the adoption of MAD has been effective. In particular, we find that after the implementation of MAD, on average, (1) the volatility of stock prices around earnings announcement declines, (2) stock prices remain closer to their post earnings announcement level during the period before earnings announcement, (3) the accuracy of analyst forecasts improves, (4) the dispersion of analyst forecasts decreases, and (5) the number of analysts following a company declines.     

期权“隐含波动率微笑”成因分析

Black-Scholes期权定价模型低估深实值和深虚值期权的现象称为“波动率微笑”。其主要原因是资产价格过程假设和市场机制因素给期权卖方的△套期保值带来了额外风险和成本。确定波动率和随机波动率研究都对BS模型做出了修正。     

Cointegration tests of present value models with a time-varying discount factor

The paper analyses the impact of persistence and volatility in the discount rate in present-value models on cointegration tests in levels and in logarithms. In simulations we find that the probability of not rejecting the null of no cointegration depends on the persistence of the discount rate process and can be very high when the expected returns process is highly persistent. In contrast, the cointegration tests are very robust with respect to the level of volatility in the discount rate. We discuss the relevance of our findings for the US stock market where standard ADF tests do not reject the null of no cointegration between stock prices and dividends. Based on estimates of persistence in four asset pricing models, we find that a model which links expected returns to the dividend yield is sufficiently persistent to explain the failure of rejecting the null that stock prices and dividends are not cointegrated.     

Analytically pricing variance and volatility swaps under a Markov-modulated model with liquidity risks

This paper determines strike prices of discretely sampled variance/volatility swaps taking into account stochastic liquidity risks and the switching of economic conditions. We adopt nonlinear regime switching volatility to reflect how asset prices are affected by economic cycles, and market prices of assets are discounted according to the level of market liquidity. We then establish a risk-neutral measure under regime switching Esscher transform, so that analytical valuation of variance/volatility swaps can be completed based on the closed-form forward characteristic function. The limiting behavior of discretely sampled variance/volatility swaps is also considered through the investigation of pricing continuously sampled variance/volatility swaps. Finally, based on the results from numerical implementation, we confirm that the new model is very flexible in reflecting different influence associated with common real market observations.     

基于股票收益的期权定价与实证分析

采用两种方法对传统的期权定价参数方法进行修正。一种是利用股票对数收益率的偏度与峰度对传统的期权定价方法计算出的期权价格进行修正,另一种是通过建立GARCH模型来预测股票收益的波动率,对传统定价方法中波动率为常数的假设进行修正。选取国电CWB1(580022)权证进行实证分析,结果表明修正得出的期权价格与实际的权证价格有很大的偏差,并对这样实证结果进行解释。     

国有控股上市公司股权激励市场效应的实证分析

本文采集了21家国有控股上市公司实施股权激励首次披露日前后三十个交易日的股票收盘价,并对这些股价进行了统计分析。实证结果显示,国有控股上市公司股票价格在股权激励方案首次披露日之后给投资者带来了超额收益,国有控股上市公司实施股权激励给个股股价带来正面的市场效应,并且能够提高国有控股上市公司的短期融资能力。分析认为,广大证券投资者没有过分担心因国有控股上市公司实施股权激励可能带来的国有资产流失问题,多数投资者持积极认同态度。