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941.
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   
942.
Does Hedging Affect Firm Value? Evidence from the US Airline Industry   总被引:1,自引:0,他引:1  
Does hedging add value to the firm, and if so, is the source of the added value consistent with hedging theory? We investigate jet fuel hedging behavior of firms in the US airline industry during 1992–2003 to examine whether such hedging is a source of value for these companies. We illustrate that the investment and financing climate in the airline industry conforms well to the theoretical framework of Froot, Scharfstein, and Stein (1993). In general, airline industry investment opportunities correlate positively with jet fuel costs, while higher fuel costs are consistent with lower cash flow. Given that jet fuel costs are hedgeable, airlines with a desire for expansion may find value in hedging future purchases of jet fuel. Our results show that jet fuel hedging is positively related to airline firm value. The coefficients on the hedging variables in our regression analysis suggest that the “hedging premium” is greater than the 5% documented in Allayannis and Weston (2001), and might be as large as 10%. We find that the positive relation between hedging and value increases in capital investment, and that most of the hedging premium is attributable to the interaction of hedging with investment. This result is consistent with the assertion that the principal benefit of jet fuel hedging by airlines comes from reduction of underinvestment costs.  相似文献   
943.
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   
944.
945.
What Kind of Voice Do Loyal Employees Use?   总被引:1,自引:0,他引:1  
This study helps clarify mixed support for Hirschman's exit–voice–loyalty framework by arguing that loyalty, or feelings of attachment to the organization, and voice are not one–dimensional constructs. Based on data gathered from a survey of employees working with a large Canadian utility organization, employees feeling attached through an affective, emotional bond are found less likely to use representative voice but more likely to use direct voice, while those attached for rational, calculated reasons are more likely to use representative voice. Employees feeling attached for either reason are found less likely to exit. Implications for theory, research, and policy are discussed.  相似文献   
946.
We examine the impact of initial public offerings (IPOs) on rival firms and find that the valuation effects are insignificant. This insignificant reaction can be explained by offsetting information and competitive effects. Significant positive information effects are associated with IPOs in regulated industries and the first IPO in an industry following a period of dormancy. Significant negative competitive effects are associated with larger IPOs in competitive industries, those in relatively risky industries, those in high‐performing industries, and those in the technology sector. IPO firms that use the proceeds for debt repayment appear to represent a more significant competitive threat to rival firms relative to IPO firms that use their proceeds for other purposes.  相似文献   
947.
This paper formalizes the commonsensical hypothesis that resource scarcity causes a large allocation of time and effort to appropriative competition. Our main innovation is to model explicitly the positive intertemporal effect of consumption on the probability of survival. The critical assumption is that this effect becomes stronger as resources become scarcer. We also show that anticipated future resource abundance increases the incremental value of survival and, consequently, amplifies the current allocation of time and effort to appropriative competition. Interestingly, if resources are currently scarce, then larger anticipated future abundance can cause a big enough increase in the time and effort allocated to appropriative competition to result in a decrease in the sum of current and expected future utility, a “paradox of anticipated abundance”.  相似文献   
948.
Monopoly, competition and information acquisition   总被引:1,自引:0,他引:1  
An incumbent monopolist is uncertain about its linear demand, but can acquire public information at a cost. We determine how an entry threat affects the firm's information acquisition. If returns to scale are constant and the state-contingent demands become more dispersed as output increases, then entry reduces information acquisition. If, however, either the incumbent or entrant has increasing returns; or if the state-contingent demands are nonlinear or fail increasing dispersion, then entry can increase information. Finally, entry can hurt consumers. Although entry always increases output, it can decrease information. Consumers sometimes prefer a better informed monopoly to a duopoly.  相似文献   
949.
Popular monthly coincident indices of business cycles, e.g. the composite index and the Stock–Watson coincident index, have two shortcomings. First, they ignore information contained in quarterly indicators such as real GDP. Second, they lack economic interpretation; hence the heights of peaks and the depths of troughs depend on the choice of an index. This paper extends the Stock–Watson coincident index by applying maximum likelihood factor analysis to a mixed‐frequency series of quarterly real GDP and monthly coincident business cycle indicators. The resulting index is related to latent monthly real GDP. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
950.
Kirzner, Israel M. (2001). Ludwig von Mises: The Man and His Economics . Wilmington, DE: ISI Books. ISBN 1-882926-61-7. xv, 226 pp.  相似文献   
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