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891.
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Rapid construction of transoceanic fiber optic cables and the successful establishment of private satellite companies with inter-regional or global coverage have fundamentally altered the environment in which international telecommunications capacity is provided. This article presents industry data and discusses market developments which document substantial competition that has emerged in international facilities-based telecommunications. Intelsat, historically the largest provider of international telecommunications capacity, has seen its market position decline rapidly for all services and all major geographic market areas worldwide.  相似文献   
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895.
On-Line Portfolio Selection Using Multiplicative Updates   总被引:6,自引:0,他引:6  
We present an on-line investment algorithm that achieves almost the same wealth as the best constant-rebalanced portfolio determined in hindsight from the actual market outcomes. The algorithm employs a multiplicative update rule derived using a framework introduced by Kivinen and Warmuth. Our algorithm is very simple to implement and requires only constant storage and computing time per stock in each trading period. We tested the performance of our algorithm on real stock data from the New York Stock Exchange accumulated during a 22-year period. On these data, our algorithm clearly outperforms the best single stock as well as Cover's universal portfolio selection algorithm. We also present results for the situation in which the investor has access to additional "side information."  相似文献   
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Purchasing power parity suggests that international price ratios for identical goods should approximate nominal exchange rates for the currencies in which the prices are denominated. Deviations of the price ratios from exchange rates can occur for a number of reasons and mixed evidence has been recorded for how long those deviations last. Empirical evidence for international restaurant prices in El Paso, Texas and Ciudad Juarez, Mexico confirms that menu item price ratios are strongly correlated with the peso/dollar exchange rate. An earlier exploratory study of eight individual products also indicated that half-life deviations in this market are very short. This study utilizes additional data from a larger and more extensive sample to examine if the prior results are confirmed.  相似文献   
899.
Based on organizational justice theories and cognitive dissonance theories, the authors hypothesized that: (a) perceived top management support for ethical behaviors will be positively correlated with all facets of job satisfaction (supervision, pay, promotion, work, co-workers, and overall); and (b) the correlation will be highest with the facet of supervision. Empirical results (n = 77 middle level managers from two organizations in South India) supported only the second hypothesis. Implications for managing a global workforce are discussed.  相似文献   
900.
Randomization and the American put   总被引:8,自引:0,他引:8  
While American calls on non-dividend-paying stocks may be valuedas European, there is no completely explicit exact solutionfor the values of American puts. We use a technique called randomizationto value American puts and calls on dividend-paying stocks.This technique yields a new semiexplicit approximation for Americanoption values in the Black-Scholes model. Numerical resultsindicate that the approximation is both accurate and computationallyefficient.  相似文献   
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