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171.
172.
Paulo N. Figueiredo Author Vitae 《Technological Forecasting and Social Change》2010,77(7):1090-1108
Most of the studies that describe the building of innovation capability in emerging and developing economies have focused on the ways in which latecomer firms develop continuously towards advanced capability levels along existing technological trajectories, particularly for the assembled products industries, especially in Asia. A slightly different approach is adopted herein by focusing on pathways of discontinuous capability building of firms in natural resource-processing industries. By drawing on evidence from a variety of case studies taken from 13 forestry, pulp, and paper firms in Brazil in the period 1950-2007, it was found that: (1) in contrast with the majority of case studies reported in the literature, the pathways followed by firms in their accumulation of innovation capability involved a qualitative departure from the established technological trajectory at an early stage in the development of their capability; (2) the pathways of firms along the new technological trajectories were nevertheless characterised by a high degree of variability (from intermediate to world leading innovators) in terms of the levels and speeds of the accumulation of innovation capability; (3) firms that have attained progressively higher levels of innovative performance have more rapidly developed a combination of internal and external research-based arrangements in order to undertake increasingly complex, but firm-centred innovation efforts. This paper sheds some light on some of the discussions that relate to the role of natural resources in the patterns of industrial progress and growth in those countries endowed with particular natural resource-based industries. It also provides a methodological contribution to the study of the long-term innovation strategies that make use of the dynamics of capability building, especially within natural resource-processing industries. 相似文献
173.
S. Colombo A. Angus J. Morris D.J. Parsons M. Brawn K. Stacey N. Hanley 《Ecological Economics》2009,68(11):2834-2841
This paper explores whether expert judgements can be taken as a proxy for citizen preferences for determining investment strategies for public goods. As an illustration, we focus on the provision of Public Rights Of Way (PROW) by Local Government Authorities in England. These provide rights of passage over property to those other than the owners, and little information is available on the welfare effects of changes in the provision and use of PROW. Given limited funds, reliance on expert judgement could be a cost effective alternative for decision-making compared with stated preference surveys of citizens. Two methods are compared. The Analytic Hierarchy Process (AHP) is used to elicit expert judgement to proxy citizen preferences for different attributes of PROW. The Choice Experiment (CE) technique is then used to derive preferences directly through personal interviews with citizens. Overall it was found that judicious use of AHP by experts can, in this instance, be used to represent citizen views. However, this result may not be easily generalisable to other settings. 相似文献
174.
We model endogenous catastrophic risk in a new way. We call it “inertia risk”, which accounts for delays between physical variables and the hazard rate – a characteristic often observed in reality. The added realism significantly affects optimal policies relative to the standard model of catastrophic risk. The probability of a catastrophe occurring at some point in time can span the entire interval [0,1], and is not 0 or 1 as is typical in standard models. Inertia risk can also generate path dependences. We illustrate the implications for policy in a simple model of climate change. 相似文献
175.
Denis Belomestny G. N. Milstein John Schoenmakers 《Decisions in Economics and Finance》2010,33(2):117-138
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
176.
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 ifWe also show that X 2:n is smaller than Y 2:n in terms of the dispersive order if and only ifMoreover, 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
$\lambda\geq \sqrt{\frac{1}{{n\choose 2}}\sum_{1\leq i < j\leq n}\lambda_i\lambda_j}.$
$ \lambda\le\frac{\sum^{n}_{i=1} \lambda_i-{\rm max}_{1\leq i\leq n} \lambda_i}{n-1}. $
177.
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
178.
179.
N. Edward Coulson Crocker H. Liu Sriram V. Villupuram 《Regional Science and Urban Economics》2013,43(6):1023-1040
We examine the relation between housing prices in an MSA and its urban economic base. We create and employ new forward-looking employment growth indices that measure the urban economic strength of an MSA and find that it accounts for a significant and sizeable portion of the house price movements in that MSA. We argue that the forward looking measure is an indicator of future agglomeration growth for the MSAs. We further partition the urban economic growth into growth by various industries and track the attribution of their growth to housing prices over time. We find that for some MSAs, home prices are driven by the same set of industries over time, whereas for others, home prices are driven by a totally new set of industries in the later quarters, due to the birth of new industries. We also analyze the impact of the diversification of an urban economic base on home price volatility and observe that diversification decreases home price volatility. The result has larger implications for urban policymakers in selecting the appropriate type of industries relative to their existing mix of industries. 相似文献
180.
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