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81.
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   
82.
Beef cattle producers were surveyed in Texas and Nebraska to investigate perceptions of sources of risk, the effectiveness of risk management strategies, and interest in further risk management education, particularly production risk, using probit analysis. Important decision variables identified are age, prior use of risk management tools, previous attendances of risk management education, and risk aversion. Severe drought and cattle price variability are identified as primary risk factors with potential to affect farm income. Extremely cold weather and disease are of less importance. Understocking pasture and storing hay are perceived most effective as risk management options.  相似文献   
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84.
A method of combining survey data and Dairy Herd Improvement Association (DHIA) records to achieve low cost farm trials is presented. Farm trials and surveys of current practices and production responses are useful to identify yield gaps between expectations predicted from experimental findings and actual field results. Different management schemes can be ranked using subjective probabilities and stochastic dominance to enhance successful implementation of research findings and to increase the feedback between researchers, extension workers, and producers. A survey of current masitis control practices and expected milk yield response is the example. Combining survey results with DHIA records allowed estimating the relationship between somatic cell counts (SCC) and milk yield. Eliciting beliefs about the relationship between SCC and milk yield showed that producers agreed with predictions from the statistical model. Subjective probabilities about SCC and mastitis control practices showed that our sample of experts and producers consistently ranked the different practices but extension agents had no consensus about the the most or least effective ones.  相似文献   
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86.
This paper reports an empirical examination of independent expert reports in takeover bids using the 170 reports that were issued in the 364 cash-based bids that occurred between January 1988 and December 1991. It was found that bid premia offered in takeover bids where an expert's report was issued were not significantly lower than bid premia in other bids. This may be attributable to independent experts acting as a countervailing influence on bidders holding a superior pre-bid bargaining position. Next, some dimensions of the “fair and reasonable” criterion that experts are required to use are examined. These are the single-test and dual-test interpretations of the phrase, the relation between offer price, market price and the expert's valuation of the target, the cost and length of expert's reports and, finally, the influence an expert has on the outcome of a bid.  相似文献   
87.
Game theoretic derivations of competitive strategies in conjoint analysis   总被引:1,自引:0,他引:1  
While conjoint analysis has been applied in a wide variety of different contexts in Marketing, most applications fail to explicitly consider retaliatory reactions from competitors. In this paper, a methodological extension is developed for conjoint analysis by explicitly modeling competition in a game theoretic context. The Nash equilibrium concept is employed to model competitive reactions to produce design, and its implications for reactive product strategies are discussed. The optimal product design problem for each firm is formulated as a nonlinear integer programming problem, which is solved via a specialized branch and bound method combined with a heuristic. In order to compute a Nash equilibrium, a sequential iterative procedure is proposed. The proposed procedure is illustrated under several scenarios of competition using previously published conjoint data.This research has been supported by the Henry Rutgers Research Fellowship, Rutgers University.  相似文献   
88.
The underidentification of linear models with measurement error does not necessarily extend to panel data models, as has been shown by GAiliches and Hausman (1986). We discuss and extend some of their results for a simple case and address particular issues concerning identification and asymptotic variances.  相似文献   
89.
Abstract. A recent article in this journal (Hsieh, Ferris, and Chen, 1990) presents evidence demonstrating that financially distressed firms that terminate overfunded pension plans experience significantly positive abnormal returns, while nondistressed terminating firms experience returns not different from zero. The article concludes from this evidence that the market regards the property rights to excess assets as residing fully with the sponsoring firm prior to termination, particularly when the sponsoring firm is not financially distressed. Accordingly, the reporting requirements of Statement of Financial Accounting Standards (SFAS) No. 88, which require immediate recognition of gains resulting from termination, are inconsistent with the market's view of the ownership rights to excess plan assets. Similarly, the article suggests that the excise tax imposed on asset reversions is “punitive” because property rights to fund assets resided with the company prior to termination. This paper questions three aspects of the Hsieh, Ferris, and Chen article: (1) the plausibility of the theory explaining differential reaction to the announcement to terminate for distressed and nondistressed firms; (2) the effect of the distressed/nondistressed classification criteria, event date specification, and event window length on the results; and (3) the appropriateness of using the empirical results, if reliable, to evaluate accounting treatment or federal tax policy. Résumé. Dans un récent article paru dans cette même publication, Hsieh, Ferris et Chen (1990) soumettaient des faits démontrant que les entreprises en difficulté financière qui mettent fin à un régime de retraite surprovisionné enregistrent des rendements anormaux positifs importants, tandis que les entreprises qui mettent fin à un régime de retraite sans être en difficulté financière enregistrent des rendements qui ne sont pas différents de zéro. De là, les auteurs concluaient que le marché estime que les droits à l'excédent d'actif appartiennent exclusivement à l'entreprise responsable du régime avant la cessation, en particulier lorsque cette dernière n'est pas en difficulté financière. Par conséquent, les exigences de la norme SFAS No. 88 en matière d'information à fournir, qui prévoient la constatation immédiate du produit de la cessation du régime, ne sont pas conformes à la façon de voir du marché relativement aux droits à l'excédent d'actif du régime. De la même façon, selon les auteurs, la taxe d'accise imposée en cas de retour de l'actif est “punitive”, étant donné que les droits à l'actif du régime appartenaient à l'entreprise avant la cessation du régime. Les auteurs s'interrogent ici sur trois aspects de l'article de Hsieh, Ferris, et Chen: 1) la pertinence de la théorie expliquant la réaction marginale à l'annonce de la cessation d'un régime pour les entreprise qui sont en difficulté financière et celles qui ne le sont pas; 2) l'incidence sur les résultats des critères permettant de classer les entreprises comme étant en difficulté financière ou ne l‘étant pas, de la précision de la date de l’événement et de la longueur de la période pré-post relative à l‘événement; et 3) l'opportunité de l'utilisation des résultats empiriques, s'ils sont fiables, pour évaluer le traitement comptable ou la politique fiscale fédérale.  相似文献   
90.
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