Implied Standard Deviations and Post-earnings Announcement Volatility

This paper investigates volatility increases following annual earnings announcements. Standard deviations implied by options prices are used to show that announcements of bad news result in a lower volatility increase than those of good news, and delay the increase by a day. Reports that are difficult to interpret also delay the volatility increase. This delay is incremental to that caused by reporting bad news, although the effect of bad news on slowing down the reaction time is dominant. It is argued that the delays reflect market uncertainty about the implications of the news.     

Dispersion of Financial Analysts' Earnings Forecasts and the (Option Model) Implied Standard Deviations of Stock Returns

This study examines whether the information implied by simultaneous levels of option and stock prices (specifically, the implied standard deviation of returns) reflects other contemporaneously available information. The independent contemporaneous measure considered is the observed dispersion (across several financial analysts), at a point in time, in the forecasts of earnings per share for a given firm. The results indicate that implied standard deviations clearly reflect the contemporaneous dispersion in analysts' forecasts incrementally, i.e., beyond the information contained in the historical time series of returns.     

Intra–day Behavior of Treasury Sector Index Option Implied Volatilities around Macroeconomic Announcements

If option implied volatility is an unbiased, efficient forecast of future return volatility in the underlying asset, then we should be able to predict its path around macroeconomic announcements from responses in cash markets. Regressions show that volatilities rise the afternoon before announcements that move cash markets, and that post–announcement volatilities return to normal as rapidly as cash prices do. Although implied volatilities are predictable, the Treasury options market is efficient since informed traders do not earn arbitrage profits once we account for trading costs.     

Stock Price Behavior Around Announcements of Write-Offs

Review of Accounting Studies - Is it plausible that important corporate events such as write-offs, averaging around 20% of firms' market values, are associated with stock-price responses of...     

The Behavior of Option Price Around Large Block Transactions in the Underlying Security

This paper investigates the behavior of stock and option prices around block trades in stocks. The results indicate that for both up tick and downtick block trades the stock prices adjust within a fifteen minute period after the block trade. Moreover, for uptick blocks there is no evidence of any stock price reaction before the block trade. However, the adjustment of stock price for downtick blocks begins about fifteen minutes before the block trade. We also find that option price behavior differs considerably from stock price behavior. Specifically, our results suggest that options exhibit abnormal price behavior starting thirty minutes before the block and ending one hour after the block. The pattern is more pronounced for downtick blocks and for put options. We interpret this abnormal price behavior of options before the block trade as consistent with intermarket frontrunning.     

Merger Announcements and Trading

We test whether an increase either in informed trades or in large liquidity trades leads to greater correlation of trading volume across markets. We confirm that both trading volume and positive returns of target companies are abnormally high before merger announcements. We find a statistically significant increase in the correlation between New York Stock Exchange and Nasdaq/regional trading volume before merger announcements. Furthermore, after merger announcements, we find evidence of both large liquidity trading and a statistically significant increase in the correlation of trading volume across markets.     

企业并购理论综述

对于企业并购的研究,现有文献主要集中在三个方面:一是从企业个体角度和宏观角度来研究企业并购动因;二是运用博弈论模型以及运用实物期权模型来分析企业并购过程,对企业并购的研究最新进展主要体现在这个研究领域;三是运用事件研究法和会计指标研究法来研究并购绩效。国有大股东和管理者在并购过程中所起的作用,以及在实物期权和博弈论的框架下研究新一轮战略并购浪潮,构成未来的研究方向。     

Binomial Option Pricing Biases and Inconsistent Implied Volatilities

We evaluate the binomial option pricing methodology (OPM) by examining simulated portfolio strategies. A key aspect of our study involves sampling from the empirical distribution of observed equity returns. Using a Monte Carlo simulation, we generate equity prices under known volatility and return parameters. We price American–style put options on the equity and evaluate the risk–adjusted performance of various strategies that require writing put options with different maturities and moneyness characteristics. The performance of these strategies is compared to an alternative strategy of investing in the underlying equity. The relative performance of the strategies allows us to identify biases in the binomial OPM leading to the well–known volatility smile . By adjusting option prices so as to rule out dominated option strategies in a mean–variance context, we are able to reduce the pricing errors of the OPM with respect to option prices obtained from the LIFFE. Our results suggest that a simple recalibration of inputs may improve binomial OPM performance.     

Volatility Implied by Option Prices: The Case of Takeover Bids

We model the effect of an impending share price jump on the implied standard deviation (ISD) of a company's options, testing the model by investigating its predictive ability for ISDs of companies subject to a takeover bid. Our model fits the observed ISDs well for all but certain deep in-the-money options. However, the model demonstrates that a discontinuity in the relationship between moneyness and the ISD both explains the combination of high and zero ISDs exhibited by these options, and impairs the predictive power of the model at these levels of moneyness.     

The Determinants of Implied Volatility: A Test Using LIFFE Option Prices

This paper presents and tests a model of the volatility of individual companies' stocks, using implied volatilities derived from option prices. The data comes from traded options quoted on the London International Financial Futures Exchange. The model relates equity volatilities to corporate earnings announcements, interest-rate volatility and to four determining variables representing leverage, the degree of fixed-rate debt, asset duration and cash flow inflation indexation. The model predicts that equity volatility is positively related to duration and leverage and negatively related to the degree of inflation indexation and the proportion of fixed-rate debt in the capital structure. Empirical results suggest that duration, the proportion of fixed-rate debt, and leverage are significantly related to implied volatility. Regressions using all four determining variables explain approximately 30% of the cross-sectional variation in volatility. Time series tests confirm an expected drop in volatility shortly after the earnings announcement and in most cases a positive relationship between the volatility of the stock and the volatility of interest rates.     

我国商业银行并购探讨

本文综述了商业银行并购的成因,特点和我国商业银行并购中应注意的问题,认为并购是我国商业银行发展的必由之路。     

Skewness and Kurtosis Implied by Option Prices: A Correction

Corrado and Su (1996) provide skewness and kurtosis adjustment terms for the Black‐Scholes model, using a Gram‐Charlier expansion of the normal density function. In this note we provide a correction to the expression for the skewness coefficient and illustrate the effect on call option prices of the error found.     

Option Prices, Implied Price Processes, and Stochastic Volatility

This paper characterizes all continuous price processes that are consistent with current option prices. This extends Derman and Kani (1994), Dupire (1994, 1997), and Rubinstein (1994), who only consider processes with deterministic volatility. Our characterization implies a volatility forecast that does not require a specific model, only current option prices. We show how arbitrary volatility processes can be adjusted to fit current option prices exactly, just as interest rate processes can be adjusted to fit bond prices exactly. The procedure works with many volatility models, is fast to calibrate, and can price exotic options efficiently using familiar lattice techniques.     

企业并购交易中的若干税收问题

理论研究与实证研究都表明税收对企业并购活动的影响是深刻的,因此借鉴发达国家处理企业并购交易中涉及到的免税条件的设立、应税所得、税率、计税成本、融资利息的扣除、税收特性的结转等重要税收问题的经验,对于完善我国企业并购的税收制度是有益的。     

企业并购的财务风险评价研究

首先对企业并购中存在的对目标企业定价、并购融资、并购价值支付及在并购后对于目标企业的财务整合风险等财务风险进行了概述,在此基础上提出了企业并购决策中财务风险评价指标体系,然后构建了企业并购中财务风险评价的二级模糊综合评价模型。最后对运用一案例对财务风险评价模型进行了实证研究,验证了模型的可行性。     

论企业并购风险

企业并购风险包括产权风险、战略风险、管理风险、财务风险等。企业并购风险主要缘于并购过程中成本的膨胀以及未能取得和发挥目标企业的核心能力,深层原因在于市场环境的动态变化、企业自身变化、对企业并购认识的相对有限等。     

论上市公司并购手段的单一性对并购的制约

由于中国并购融资手段的单一性,并购主体难以利用资本市场的融资便利条件进行融资,使国际通行的杠杆收购无法实现。而由于股权分割,换股并购在中国也缺乏现实的操作基础。因此,中国应该放松并购的融资管制,实现股票的全面流通,为企业进行大规模的战略性并购创造条件。     

资产评估与上市公司并购重组

证券市场发展10多年来,上市公司并购重组活动快速发展,数量不断增多,形式日趋多样,涉及金额也越来越大,逐渐成为我国产业结构战略调整、上市公司优胜劣汰、社会资源优化配置的重要手段.