税收对经理人股票期权激励效应的影响

股票期权的实施某种程度上是追求税收利益最大化的结果.税收因素因为决定实施股票期权的企业和经理人的现金收入,而影响企业授予经理人股票期权的行为,以及经理人持有行权所得股票的时间、股利政策和盈余管理等.税收的行为调节既可能促进股票期权的激励效应,也可能抵消其激励作用.因此,如何协调宏观层面的税收政策制定与微观层面委托代理问题的缓解是未来应该关注的问题.     

经理人股票期权会计确认的探讨

经理人股票期权的确认问题是亟待解决的会计理论和实践问题。经理人股票期权的经济实质是企业经理人参与企业剩余索取权的分享。经理人股票期权是一项无形资产,应在经理人提供劳动期间内,将其平均摊销。应改革现行的财务会计观念与模式,增设“待转股本准备”科目,以适应企业经理人参与现代企业剩余索取权分享的现实。     

Valuation of a Repriceable Executive Stock Option

We introduce a path-dependent executive stock option. The exercise price might be reduced when both the firm’s stock price and a stock market index fall greatly. The repriceable executive stock option has a simple payoff that may be used for realistic executive rewards. We show the valuation formula, and compute the probability of the repriceable executive stock option expiring in-the-money. Both price and probability are important pieces of quantitative information when choosing an executive compensation package.     

Executive Stock Option Exercise and Seasoned Equity Offerings

We examine executive stock option exercises around a sample of 1,268 seasoned equity offerings (SEOs) from 1996 to 2004 focusing on a subset of exercises we identify as potentially informed. Consistent with the theory that firms issue equity when stock is overvalued, we document a surge in informed exercise in the months surrounding the SEO. From six months prior to the announcement date to six months after issuance, an average 1.76% of the total market capitalization for issuing firms is exercised and sold. Interestingly, we find a positive association between informed option exercises and long-run performance. Overall, our collective evidence indicates that insiders are not particularly good at timing exercises around SEOs.     

经理人股票期权理论及其模型分析

经理人股票期权是为了适应现代企业制度的需要,对经理人员实行的行之有效的约束激励机制,其本质就是让拥有控制权的经理人员一方面能够拥有一定的剩余索取权,另一方面还要承担相应的风险,从而激励经理人最大限度地维护企业所有者的利益。本文通过阐述经理人股票期权的激励作用,提出了期权理论模型,进而使经理人建立长期激励的良性循环具有指导意义。     

完善经理股票期权激励与公司治理的策略

经理股票期权在西方国家的广泛应用证明了它是一种比较有效的激励手段.在我国公司治理中引进经理股票期权制度将有利于规范经理人市场和资本市场的运作.为了使经理股票期权制度的运作能有一个良好的内外部环境,我们在实施经理股票期权制度的进程中必须加强规范经理股票期权的来源、授权范围、行权价格、授权数量、行权期限及其相关的法律制度建设.     

The Manipulation of Executive Stock Option Exercise Strategies: Information Timing and Backdating

I identify three option exercise strategies executives engage in, including (i) exercising with cash and immediately selling the shares, (ii) exercising with cash and holding the shares, and (iii) delivering some shares to the company to cover the exercise costs and holding the remaining shares. Stock price patterns suggest executives manipulate option exercises. They use private information to increase the profitability of all three strategies, and likely backdated some exercise dates in the pre‐Sarbanes‐Oxley period to enhance the profitability of the latter two strategies, where the executive's company is the only counterparty. Backdating is associated with reporting of internal control weaknesses.     

The Effect of Executive Stock Options on Corporate Innovative Activities

This study investigates whether the implicit optionality of executive stock options (ESOs) induce managers to undertake innovative activities associated with various types of risk. We find ESO risk incentive (vega) to be positively correlated with all types of corporate innovations. We also find greater ESO risk incentive effects for the product‐related innovative activities that are associated more with systematic risk than idiosyncratic risk. Finally, we document the following pecking order for the ESO risk incentive effects: improved product, new product, alliance, and new research and development. Our results suggest that executives have more incentive to invest in projects with higher systematic risk.     

The Effect of Exercise Date Uncertainty on Employee Stock Option Value

The IASC recently recommended that employee compensation in the form of stock options be measured at the 'fair value' based on an option pricing model and the value should be recognized in financial statements. This follows adoption of SFAS No. 123 in the United States, which requires firms to estimate the value of employee stock options using either a Black‐Scholes or binomial model. Most US firms used the B‐S model for their 1996 financial statements. This study assumes that option life follows a Gamma distribution, allowing the variance of option life to be separate from its expected life. The results indicate the adjusted Black‐Scholes model could overvalue employee stock options on the grant date by as much as 72 percent for nondividend paying firms and by as much as 84 percent for dividend paying firms. The results further demonstrate the sensitivity of ESO values to the volatility of the expected option life, a parameter that the B‐S model or a Poisson process cannot accommodate. The variability of option life has an especially big impact on ESO value for firms whose ESOs have a relatively short life (5 years, for example) and high employee turnover. For such firms, the results indicate a binomial option pricing model is more appropriate for estimating ESO value than the B‐S type model.     

对股票期权的思考--股票期权在我国企业的适用性研究

起源于美国的股票期权制度在其本土已经得到了较为广泛的应用，我国在这方面也进行了积极的探索，一些企业也进行了实践。但股票期权究竟是否适合我国的情况呢?本将以主板市场为基础，通过对股票期权的实施条件的分析来对其在我国企业的适用性进行研究。     

股票期权的实践与探讨

作为分配制度变革的股票期权计划，在发达国家运用已有近30年的历史，成为企业一种有效的激励机制。随着我国企业改革的深化与市场经济的确立，急需探索一条科学有效的激励机制。在我国现行的法律体系下，股票期权计划这种长期激励机制吸引了越来越多的注意力。本对我国在推行股票期权计划的实践中所产生的一些问题作了初步的探讨。     

Managerial Risk-Taking Incentives and Executive Stock Option Repricing: A Study of US Casino Executives

I examine the relation between managerial incentives from holdings of company stock and options and stock option repricing. Because options provide incentives to increase both risk and stock price, firms must realize that as options go underwater, executives might face incentives to invest in risky, negative NPV projects. Repricing may alleviate such incentives. I examine repricing activity by firms in the US gaming industry and find that risk-taking incentives from options are positively related to the incidence of executive option repricing. The results support the hypothesis that repricing assists firms in alleviating excessive risk-taking incentives of senior management.     

The Option and Decision to Repurchase Stock

Open‐market repurchase programs provide firms with the flexibility to manage the cash and risk aspects of their operations. We examine at which stage cash and risk matter in the typical stages of a repurchase program: announcement, implementation, and withdrawal. Cash and risk considerations appear to matter only at the implementation stage, and partially negate the traditional signaling effect around program announcement.     

The Informational Role of Stock and Option Volume

This article analyzes the intraday interdependence of orderflows and price movements for actively traded NYSE stocks andtheir Chicago Board Options Exchange (CBOE)-traded options.Stock net trade volume (buyer-initiated volume minus seller-initiatedvolume) has strong predictive ability for stock and option quoterevisions, but option net trade volume has no incremental predictiveability. This suggests that informed investors initiate tradesin the stock market but not in the option market. On the otherhand, both stock and option quote revisions have predictiveability for each other. Thus, while information in the stockmarket is contained in both quote revisions and trades, informationin the option market is contained only in quote revisions.     

Investment Plans and Stock Returns

When the discount rate falls, investment should rise. Thus with time-varying discount rates and instantly changing investment, investment should positively covary with current stock returns and negatively covary with future stock returns. Aggregate nonresidential U.S. investment contradicts both these implications, probably because of investment lags. Investment plans, however, satisfy both implications. These investment plans, from a U.S. government survey of firms, are highly informative measures of expected investment and explain more than three-quarters of the variation in real annual aggregate investment growth. Plans have substantial forecasting power for excess stock returns, showing that time-varying risk premia affect investment.     

基于事件研究法的A股市场股权激励效应实证分析

本文以2010年沪深两市推出股权激励方案的90家上市公司为样本,选取公告日前5日至公告日后20日为事件窗口,运用事件研究法就股权激励推出对上市公司股价影响进行实证研究.结果表明:中国股市呈现明显的股权激励效应,股权激励公告发布前后股票产生持续的累计异常正收益;由于信息不对称,部分投资者通常会借助内幕信息提前买入,并获得可观的超额收益,而普通投资者在公告发布后买入只能获得小部分的超额收益并且需要承担更大的风险.     

Skewness and Stock Option Prices

Abstract

In the classical Black-Scholes model, the logarithm of the stock price has a normal distribution, which excludes skewness. In this paper we consider models that allow for skewness. We propose an option-pricing formula that contains a linear adjustment to the Black-Scholes formula. This approximation is derived in the shifted Poisson model, which is a complete market model in which the exact option price has some undesirable features. The same formula is obtained in some incomplete market models in which it is assumed that the price of an option is defined by the Esscher method. For a European call option, the adjustment for skewness can be positive or negative, depending on the strike price.     

The Relationship Between Stock and Option Price Changes

This paper documents an important step in reconciling conflicting results by Manaster and Rendleman [16] and Stephan and Whaley [21] regarding price change relationships between options and their underlying stocks. Using recent advances in bi-directional causality testing and data sources available only fairly recently, statistical tests are conducted that mitigate the nonsynchroneity and bid-ask bias problems that may have affected the Manaster and Rendleman [16] study. Even with these adjustments, empirical results are consistent with Manaster and Rendleman [16], indicating that stock price changes adjust to lagged option price changes over two trading days. Moreover, results suggest that the causality is bi-directional.     

Stock Option Measures and the Stock Repurchase Decision

The major purposes of this study are two fold. First, we investigate whether or not the dilutive effect from stock options on the denominator of earnings per share is associated with the incurrence of stock repurchases. We use the FASB dilution and the economic dilution as the direct dilution measures and examine their relationship with stock repurchase decision. Second, we explore which of the extant measures of stock options can better explain the incurrence of stock repurchases. Six extant measures of stock options from previous studies are used: (1) the FASB's treasury-stock EPS dilution method, (2) the economic dilution measure based on Core, Guay and Kothari (2002), (3) the number of employee stock option exercises, (4) the number of stock option grants, (5) the number of total stock options outstanding, and (6) the number of exercisable stock options.Using a pooled cross-sectional sample from 1996–2000, we find a positive association between the likelihood of stock repurchases and the FASB dilution as well as the economic dilution in EPS, respectively. Thereby providing support for the undo-dilution hypothesis. The highest incremental explanatory power is found when we add the number of stock options exercisable to the baseline model. However, further analysis does not support the option-funding hypothesis suggested by Kahle (2002). We provide two explanations for why exercisable stock options better explain the stock repurchase decision.