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41.
This paper gives a tree-based method for pricing American options in models where the stock price follows a general exponential Lévy process. A multinomial model for approximating the stock price process, which can be viewed as generalizing the binomial model of Cox, Ross, and Rubinstein (1979) for geometric Brownian motion, is developed. Under mild conditions, it is proved that the stock price process and the prices of American-type options on the stock, calculated from the multinomial model, converge to the corresponding prices under the continuous time Lévy process model. Explicit illustrations are given for the variance gamma model and the normal inverse Gaussian process when the option is an American put, but the procedure is applicable to a much wider class of derivatives including some path-dependent options. Our approach overcomes some practical difficulties that have previously been encountered when the Lévy process has infinite activity.  相似文献   
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For a compound Poisson process with negative drift and jump distribution consisting of a mixture of exponentials on [0) and on (-, 0), an exact expression is derived for the probability of hitting the level c, c > 0. the problem is motivated by modeling the returns from trading on financial markets.  相似文献   
44.
This paper develops two new methods for conducting formal statistical inference in nonlinear dynamic economic models. The two methods require very little analytical tractability, relying instead on numerical simulation of the model's dynamic behaviour. Although one of the estimators is asymptotically more efficient than the other, a Monte Carlo study shows that, for a specific application, the less efficient estimator has smaller mean squared error in samples of the size typically encountered in macroeconomics. The estimator with superior small sample performance is used to estimate the parameters of a real business cycle model using observed US time-series data.  相似文献   
45.
Abstract. We experimentally investigate the effects of a mandatory increase in education on the market for professional labor services when several service qualities are assumed to exist. We show that when suppliers have insufficient incentives to offer high-quality services in a free market, an increase in mandatory education can improve the coordination of supplier decisions and increase efficiency. If suppliers voluntarily provide a sufficient quantity of high-quality services, an education constraint can have the opposite effect. In both instances, however, an increase in the mandatory level of education can be expected to reduce the price of high-quality services while increasing the price of lower service qualities. Résumé. Les auteurs ont procédé à une analyse expérimentale des conséquences qu'aurait une hausse imposée du niveau d'études sur le marché des services professionnels, si l'on suppose l'existence de plusieurs qualités de services. L'analyse démontre que lorsque les stimulants sont insuffisants pour inciter les fournisseurs à offrir des services professionnels de qualité supérieure dans un marché libre, une hausse imposée du niveau d'études peut améliorer la coordination des décisions des fournisseurs et augmenter l'efficience. Si toutefois les fournisseurs offrent de leur propre chef une quantité suffisante de services de qualité supérieure, le fait d'imposer un niveau d'études supérieur peut avoir l'effet contraire. Dans les deux cas, on peut s'attendre à ce qu'une hausse du niveau d'études obligatoire réduise le prix des services de qualité supérieure tout en augmentant le prix des services de qualité plus faible.  相似文献   
46.
Previous empirical research indicates that corporate insiders tend to increase (decrease) their shareholdings before events that increase (decrease) firm value. More recent evidence suggests, however, that passage of the Insider Trading Sanctions Act of 1984 (ITSA) may have deterred this behavior. Our results indicate that before passage of the ITSA, insiders exploited their access to nonpublic information by selling shares before the announcement of equity issues. However, after passage of the ITSA insiders no longer displayed this behavior. We conclude the ITSA has a deterrent effect, which is more heavily concentrated on insiders at the highest level of the firm who are most visible to regulators and other market participants.  相似文献   
47.
In this paper we investigate the effect of golden parachute (GP) adoptions on shareholder wealth. We control for the potential effect a GP adoption has on the probability that a firm will receive a takeover bid by investigating the wealth effects for firms that are in play when the GP is adopted. We find that announcements are wealth neutral when firms are in play and wealth increasing when firms are not in play when a GP is adopted. The results suggest that GPs have no influence on the success of a tender offer, refuting the hypotheses that they either align manager and shareholder interests or that they entrench inefficient managers. The difference in the results for in-play and not-in-play firms is consistent with the hypothesis that GPs signal an increased likelihood that a firm will receive a takeover bid.  相似文献   
48.
This paper adopts property rights and organization theory perspectives to analyze the process of privatization of state enterprises and performance of newly created shareholding corporations in China. Relying on case study information, the paper concludes that although the shareholding corporations have contributed, to a certain extent, to better performance, their potentials have not been fully realized due to various economic environmental and ideological constraints.  相似文献   
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50.
We study the panel dynamic ordinary least square (DOLS) estimator of a homogeneous cointegration vector for a balanced panel of N individuals observed over T time periods. Allowable heterogeneity across individuals include individual‐specific time trends, individual‐specific fixed effects and time‐specific effects. The estimator is fully parametric, computationally convenient, and more precise than the single equation estimator. For fixed N as T→∞, the estimator converges to a function of Brownian motions and the Wald statistic for testing a set of s linear constraints has a limiting χ2(s) distribution. The estimator also has a Gaussian sequential limit distribution that is obtained first by letting T→∞ and then letting N→∞. In a series of Monte‐Carlo experiments, we find that the asymptotic distribution theory provides a reasonably close approximation to the exact finite sample distribution. We use panel DOLS to estimate coefficients of the long‐run money demand function from a panel of 19 countries with annual observations that span from 1957 to 1996. The estimated income elasticity is 1.08 (asymptotic s.e. = 0.26) and the estimated interest rate semi‐elasticity is ?0.02 (asymptotic s.e. = 0.01).  相似文献   
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