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41.
42.
This study investigates how participating in strategic alliances with rivals affects the relative competitive positions of the partner firms. The paper builds on studies that show significant differences in the outcomes of scale and link alliances. The study argues that the more asymmetric outcomes of link alliances translate into greater changes in the relative market shares of the partner firms, due to unbalanced opportunities for inter‐partner learning and learning by doing. We find support for this argument by examining 135 alliances among competing firms in the global automobile industry, from 1966 to 1995. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
43.
Nonstandard probability theory and stochastic analysis, as developed by Loeb, Anderson, and Keisler, has the attractive feature that it allows one to exploit combinatorial aspects of a well-understood discrete theory in a continuous setting. We illustrate this with an example taken from financial economics: a nonstandard construction of the well-known Black-Scholes option pricing model allows us to view the resulting object at the same time as both (the hyperfinite version of) the binomial Cox-Ross-Rubinstein model (that is, a hyperfinite geometric random walk) and the continuous model introduced by Black and Scholes (a geometric Brownian motion). Nonstandard methods provide a means of moving freely back and forth between the discrete and continuous points of view. This enables us to give an elementary derivation of the Black-Scholes option pricing formula from the corresponding formula for the binomial model. We also devise an intuitive but rigorous method for constructing self-financing hedge portfolios for various contingent claims, again using the explicit constructions available in the hyperfinite binomial model, to give the portfolio appropriate to the Black-Scholes model. Thus, nonstandard analysis provides a rigorous basis for the economists' intuitive notion that the Black-Scholes model contains a built-in version of the Cox-Ross-Rubinstein model.  相似文献   
44.
This study shows that firms in the pharmaceutical industry experience decreasing returns to scale in R & D as the level of R & D expenditures rises. The paper presents the results of our study of the innovative output of 16 pharmaceutical firms over a 19 year period. Given the strong correlation between R & D budgets and firm size, our study suggests the wave of mergers in the industry may yield less innovative productivity than managers expect.  相似文献   
45.
近年来,我国零售商供应商矛盾突出,引起了各方关注。商务部等五部委发布的《零售商供应商公平交易管理办法》,是近年来专门调整零供关系的政府部门规章,在稳定流通秩序方面发挥了一定的作用,但对此也有一些不同观点。为完善零供(买卖)关系的法律规范体系,推进和谐商业环境及商事法治建设,本文对调整零供关系的法律属性,少数零售企业恶意占压、骗取供应商贷款的综合治理,风险预誓机制等相关问题提出了自己的一些见解。  相似文献   
46.
本文分析了现阶段养老保险中人口老龄化的压力日益加剧,覆盖范围明显过窄,已入保群体“空账运行”,养老待遇过低等问题,提出了提高退休年龄、降低缴费比率、将社会统筹基金与个人账户基金实行分账管理、让基金保值增值加快社会保障制度立法等若干相关政策建议。  相似文献   
47.
在农村消费市场存在差异的条件下,全国范围的以行政补贴和市场推广相结合的“万村千乡”推广方式将面临“推广悖论”,即工程的普遍服务职能与企业追求利润的目标之间的冲突,进而可能会造成财政补贴资金的浪费。应在不同区域采用不同的推广策略:发达地区农村,应以企业自主经营为主;具有一定消费市场潜力但企业开拓成本还比较高的地区,应行政补贴和市场推广相结合;尚不具备经营条件的农村地区,应加强基础设施建设,并提高农民收入水平,待时机成熟后再逐步推进。  相似文献   
48.
This article classified gas exploration risk on the basis of the characteristics of oil-gas exploration investment projects, which are internal systems risk and external non-systemic risk. It described each classification specifically and introduced the basic principles and mathematical model of the multi-factor hierarchical fuzzy comprehensive judgment in detail, and then researched the conducts the risk of the gas exploration with examples.  相似文献   
49.
Graphical models provide a powerful and flexible approach to the analysis of complex problems in genetics. While task-specific software may be extremely efficient for any particular analysis, it is often difficult to adapt to new computational challenges. By viewing these genetic applications in a more general framework, many problems can be handled by essentially the same software. This is advantageous in an area where fast methodological development is essential. Once a method has been fully developed and tested, problem-specific software may then be required. The aim of this paper is to illustrate the potential use of a graphical model approach to genetic analyses by taking a very simple and well-understood problem by way of example.  相似文献   
50.
We provide evidence on the impact of tax incentives and financial constraints on corporate R&D expenditure decisions. We contribute to extant research by comparing R&D expenditures in the United States and Canada, thereby exploiting the differences in the two countries' R&D tax credit mechanisms and generally accepted accounting principles. The two tax incentive mechanism designs are consistent with differing views of the degree of financial constraints faced by firms in these economies. Our sample also allows us to explore the effects of capitalizing R&D on Canadian firms. Employing a matched design, we document relations between tax credit incentives and R&D spending consistent with both Canadian and U.S. public companies responding as though they are not financially constrained. We estimate that the Canadian credit system induces, on average, $1.30 of additional R&D spending per dollar of taxes forgone while the U.S. system induces, on average, $2.96 of additional spending. We also find that firms that capitalize R&D costs in Canada spend, on average, 18 percent more on R&D. Collectively, this evidence is important to the ongoing debates in both countries concerning the appropriate design of incentives for R&D and is consistent with the assumptions found in the U.S. tax credit system, but not those found in the Canadian system.  相似文献   
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