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61.
62.
We study how the sequence of financing of R&D varies according to the ease with which property rights over knowledge can be defined. There are two financiers: a venture capitalist (VC) and a corporation. The knowledge acquired in costly research becomes embodied in the researcher's human capital, and she may hold up the financier and walk away with the project to develop it elsewhere. The main results are: (1) When property rights are strong, research is always funded by the VC, development is performed efficiently, and breakaways from the VC to the corporation are observed in equilibrium. (2) When property rights are weak, projects may be financed by the VC or the corporation, or may remain unfunded. (3) When property rights are weak, no breakaways occur in equilibrium; local spillovers and strong product market competition increase the likelihood that research projects will get funding. (4) The equilibrium sequence of R&D finance need not be first-best efficient. (5) In equilibrium, and controlling for the strength of property rights, VCs finance projects that are more profitable on average.  相似文献   
63.
For reasons of time constraint and cost reduction, censoring is commonly employed in practice, especially in reliability engineering. Among various censoring schemes, progressive Type-I right censoring provides not only the practical advantage of known termination time but also greater flexibility to the experimenter in the design stage by allowing for the removal of test units at non-terminal time points. In this article, we consider a progressively Type-I censored life-test under the assumption that the lifetime of each test unit is exponentially distributed. For small to moderate sample sizes, a practical modification is proposed to the censoring scheme in order to guarantee a feasible life-test under progressive Type-I censoring. Under this setup, we obtain the maximum likelihood estimator (MLE) of the unknown mean parameter and derive the exact sampling distribution of the MLE under the condition that its existence is ensured. Using the exact distribution of the MLE as well as its asymptotic distribution and the parametric bootstrap method, we then discuss the construction of confidence intervals for the mean parameter and their performance is assessed through Monte Carlo simulations. Finally, an example is presented in order to illustrate all the methods of inference discussed here.  相似文献   
64.
Let X 1, . . . , X n be independent exponential random variables with respective hazard rates λ1, . . . , λ n , and Y 1, . . . , Y n be independent and identically distributed random variables from an exponential distribution with hazard rate λ. Then, we prove that X 2:n , the second order statistic from X 1, . . . , X n , is larger than Y 2:n , the second order statistic from Y 1, . . . , Y n , in terms of the dispersive order if and only if
$\lambda\geq \sqrt{\frac{1}{{n\choose 2}}\sum_{1\leq i < j\leq n}\lambda_i\lambda_j}.$
We also show that X 2:n is smaller than Y 2:n in terms of the dispersive order if and only if
$ \lambda\le\frac{\sum^{n}_{i=1} \lambda_i-{\rm max}_{1\leq i\leq n} \lambda_i}{n-1}. $
Moreover, we extend the above two results to the proportional hazard rates model. These two results established here form nice extensions of the corresponding results on hazard rate, likelihood ratio, and MRL orderings established recently by Pǎltǎnea (J Stat Plan Inference 138:1993–1997, 2008), Zhao et al. (J Multivar Anal 100:952–962, 2009), and Zhao and Balakrishnan (J Stat Plan Inference 139:3027–3037, 2009), respectively.
  相似文献   
65.
66.
Los autores comparan las normativas sobre vacaciones y licencias susceptibles de facilitar el equilibrio entre vida profesional y familiar de Australia, Canadá, República de Corea, Estados Unidos, Europa occidental y Japón utilizando un índice compuesto para clasificarlas. Los Estados Unidos figuran en último lugar: la concesión de vacaciones anuales al trabajador no es obligatoria y las licencias por motivos familiares se limitan a 12 semanas al año. Este bajo nivel de reglamentación podría deberse, según los autores, a una concepción mercantilista del empleo sumada a la creencia de que empleador y trabajadores tienen idéntica capacidad de negociación, visión no compartida por las demás democracias industrializadas.  相似文献   
67.
Regional integration: an empirical assessment of Russia   总被引:1,自引:0,他引:1  
Using a statistical model of commodity trade, we quantify the evolution of regional economic integration within Russia during 1995–1999, and explore potential determinants of this evolution. Our integration measure exhibits rich regional variation that, when aggregated to the national level, fluctuates substantially over time. In accounting for this behavior, we draw in part on theoretical models that emphasize the potential role of openness to international trade and regional disparities in income in threatening economic integration. Controlling for a host of additional regional- and national-level variables, we find a strong negative correspondence between openness to international trade and internal economic integration.  相似文献   
68.
This paper empirically examines the acquisition of a technology from a source outside the firm and its incorporation into a new or existing operational process. We refer to this key activity in process innovation as external technology integration. This paper develops a conceptual framework of external technology integration based on organizational information processing theory and technology management literature. The primary hypothesis underlying the conceptual framework is that external technology integration will be most successful when the level of interaction between the source of the technology and recipient of the technology is appropriately matched, or fit, to the characteristics of the technology to be integrated. The conceptual framework also develops other hypotheses relating to contextual factors that may also influence the success of external technology integration. A cross-sectional survey methodology is employed to test the four hypotheses of the conceptual framework, with the results indicating strong support for the fit hypothesis and general support for the contextual hypotheses. The paper closes with a discussion of the implications of this study for both theory and practice.  相似文献   
69.
70.
In this article, we propose several pathwise and finite difference-based methods for calculating sensitivities of Bermudan options using regression methods and Monte Carlo simulation. These methods rely on conditional probabilistic representations that allow, in combination with a regression approach, for efficient simultaneous computation of sensitivities at many initial positions. Assuming that the price of a Bermudan option can be evaluated sufficiently accurate, we develop a method for constructing deltas based on least squares. We finally propose a testing procedure for assessing the performance of the developed methods and give a numerical illustration.  相似文献   
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