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71.
We characterize optimal time profiles of risk-reducing expenditures and wreck probabilities for petroleum platforms. The input to our analysis is the development of wreck cost, direct and imputed. Particular attention is paid to the question of how private companies deviating from socially optimal standards may be induced to comply with such standards by means of a) a time-variant penalty, b) a no-wreck bonus and c) a time-invariant penalty.  相似文献   
72.
This article discuss in a tentative way what determines the effect of technological discontinuities on the competitive position. of companies within an industry. Three cases of technological change are anahzed: the change from manual to romputer numericalb controlled metal cutting machine tools, the change from stand-alone machine tools to flexible manufacturing systems; and the change from non-cellular to cellular mobile telephony It is argued that the character of technological discontinuity affects market shares, by altering the barriers to entry and mobility, and by being more or less in accordance with the different firms' vision about the future, implying variations in the time needed to detect and accept the new threat or opportunity. A technological discontinuity that includes a new threat or opportunig. A technological discontinuip that involues a new generic technology which substitutes for rather than adds to the previous technology base is seen as being most disruptive. The time actualb available for detecting the need to change and to act is limited by the market growth of the new product (the 'speed of diffusion between users). The faster the difficulties is, therefore diffusion is the greater are the possinbilities that early movers will fain intial advantages. Furthermore, the faster the diffusion is the greater are the possibilities that early movers will build sustanable, volume-related entry and mobility barries.  相似文献   
73.
In this article we show that quantitative methods for multi-criteria evaluation have three serious shortcomings. First, the addition of an alternative which has bad criterion scores may distort the comparison between other alternatives. Second, the addition of a criterion which does not differentiate between alternatives may distort the comparison between alternatives. Third, when a ranking of alternatives is derived from a multi-criteria evaluation, it suggests complete transitivity. It is shown that intransitivity may occur.Therefore a stepwise procedure is recommended. It involves the removal of all criteria which do not or hardly differentiate between the alternatives and a pairwise evaluation of alternatives.  相似文献   
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Summary A sequential testing procedure called 2-SPRT for the meanμ of the negative binomial distribution with known exponentk is presented. For any fixedμ 0(μ 1<μ 0<μ 2), the 2-SPRT provides an asymptotic solution to the modified Kiefer-Weiss problem. Determination ofμ 0 such that the test provides an approximate solution to the Kiefer-Weiss problem is described. The behavior of the 2-SPRT and the Sequential Probability Ratio Test is investigated using Monte Carlo methods. The error probabilities and the average sample numbers are compared. All the computations were carried out on the Alabama Supercomputer.  相似文献   
76.
S. Wang 《Metrika》1991,38(1):259-267
Summary Using Silverman and Young’s (1987) idea of rescaling a rescaled smoothed empirical distribution function is defined and investigated when the smoothing parameter depends on the data. The rescaled smoothed estimator is shown to be often better than the commonly used ordinary smoothed estimator.  相似文献   
77.
The literature on industrial organization contains very little direct evidence on the effects of actual mergers. This study estimates the effects of two recent airline mergers approved by the Department of Transportation over the objection of the Department of Justice. The merger of TWA and Ozark appears to have caused a slight increase in fares and a far greater reduction in service on city pairs out of St Louis. The merger of Northwest and Republic appears to have caused a significant increase in fares and a significant reduction in overall service on city pairs out of Minneapolis-St Paul.  相似文献   
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In this paper we consider the potential gain of a government pursuing a two-part trade policy: an import license for entry, along with a per-unit tariff on imports. The model is a two-stage game of complete but imperfect information. In the first stage, the domestic government sets trade policy, while in the second stage the home and foreign producers behave as Cournot competitors. The paper demonstrates that the optimal trade policy depends upon the number of firms, the degree of heterogeneity in cost functions, and the degree of convexity in cost functions.  相似文献   
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