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61.
62.
We test whether “detrended fluctuation analysis” (DFA)—an econophysics method—identifies the transition from efficient-market trading to herding behavior and the rise of the NASDAQ dot.com stock market bubble. DFA divides a time series into “segments” of varying lengths and then tests whether power-law distributions exist within the segments. A power-law distribution of stock-price changes within a segment indicates herding behavior and the start of the dot.com bubble. The clarity of the transition indication depends on both segment lengths and segment starting dates. Our findings show that DFA can be used to identify the beginning of stock-market bubbles but not the beginning of crashes.  相似文献   
63.
The literature on mergers has extensively analyzed the decision to merge by private firms, but it has not considered the decision to merge by private and public firms. We assume that when a private firm and a public firm merge (or when one of them acquires the other), they set up a multiproduct firm in which the government owns an exogenous percentage stake. In this framework, we show that the decision to merge by firms depends on the degree to which goods are substitutes and on the percentage of the shares owned by the government in the multiproduct firm.  相似文献   
64.
This empirical article analyses the importance of information and communications technologies (ICT) in the technological diversification trend among the world's largest manufacturing firms during the 1980s and 1990s. The objective of the research is twofold: first, to emphasise the emerging differences among technologies when companies from different industries patent outside their traditional technological capabilities; secondly, to investigate whether the tendency among large companies from all industries to patent in ICT is distinctive when compared with the tendency to patent in other technologies. We find that technological diversification in large companies has clearly occurred in ICTs. Non-ICT specialist industries increasingly develop, rather than just utilise, the cluster of ICT-related technologies. We conclude that the development of corporate capabilities in the key technologies of the emerging ICT paradigm is more widespread than previously emphasised in the literature. One implication of this observation is that technological diversification and the information revolution may be related phenomena.  相似文献   
65.
Nowadays, helicopters have been used in maritime transportation to serve offshore platforms. This paper outlines methodology for assessing safety risks by operating in the vicinity of helidecks. During each flight, decisions must be made regarding the events that involve interactions between the four safety risk elements – the pilot in command, the aircraft, the environment and the operation. This paper evaluates helicopter crash statistics based on region and flight phase. Data collected were used for developing methodology for computing the helicopter impact frequency into facility of interest. The analysis for helicopter impact frequency calculations is based on number of operations, crash rate, frequency, average length of flight and crash area. Furthermore, the conclusion was defined based on future measurements for helicopter accidents mitigation or reduction. The presented paper contributes to safety risk assessment in helicopter maritime operations.  相似文献   
66.
Given the importance in recent years of the phenomenon of academic entrepreneurship in European universities, knowledge about determinants and performance of this technology transfer mechanism may have important managerial and policy implications. Applying the resource-based view at universities, we have tested the influence of five bundles of resources and capabilities on spin-off activity rates as well as on the performance of new spin-offs in a sample of seven European universities. These five bundles are: technology transfer policies and strategies; human capital; stock of technology; resources and capabilities of technology transfer offices; and support measures for academic entrepreneurship. Our results show that excellence of human capital and the presence of university-based financial support measures are strongly associated with both spin-off activity and performance. Another interesting finding is related to the availability of university-based non-economic support measures (training, counselling, etc.), which have no influence on spin-off activity but are significantly associated with performance of new spin-offs. We also discuss some interesting relationships between explanatory variables.  相似文献   
67.
Justifying ridge regression from a geometrical perspective is one of the main contributions of this paper. To the best of our knowledge, this question has not been treated previously. This paper shows that ridge regression is a particular case of raising procedures that provide greater flexibility by transforming the matrix X associated with the model. Thus, raising procedures, based on a geometrical idea of the vectorial space associated with the columns of matrix X , lead naturally to ridge regression and justify the presence of the well-known constant k on the main diagonal of matrix X X . This paper also analyses and compares different alternatives to raising with respect to collinearity mitigation. The results are illustrated with an empirical application.  相似文献   
68.
Institutional environment influences the perceptions of desirability and feasibility, society’s social and cultural environment, such as beliefs, values and attitudes, conditions behaviour and decisions made by individuals. This research evaluates the influence of institutional environment on entrepreneurial intention using a comparative analysis of different attitudes among university students in two countries: Portugal and Spain. In particular, this study aims to examine the perceptions of desirability, feasibility and intention toward the creation of one’s own business and how that variables influence the entrepreneurial intention as compared these two different institutional contexts. Results revealed difference among attitudes toward entrepreneurship in both countries. With respect to the perception of feasibility, the majority of students in Extremadura (Spain) consider that it is easier to create a business in nowadays than it was several decades ago. However, from the students of Beira Interior (Portugal) consider that it is more difficult. Furthermore, in Extremadura, the entrepreneurial intention is higher than in Beira Interior.  相似文献   
69.
Dragiša Stojanović 《Socio》1984,18(3):167-169
This paper is concerned with some aspects of direct and indirect growth rates of sectors and with the model based on the matrix of economic growth. The purpose of this consideration is to determine through indirect growth rates the growth structure of economy and to construct the model which may be used for the planning goals. In other words, by means of the matrix of growth or the model which is based on it we can estimate the future development of the economy. This can be done under different assumptions no matter whether relations are transfered from the past into the future or whether various relations change in future periods on the basis of streamlined elements of the plan. Hence, it can be determined either from the assumption that past relations will be kept approximately in the same frames, or that they will change in the future. In each case all the changes can be described through direct and indirect growth rates.  相似文献   
70.
以海南国际旅游岛建设为背景,对海南省高校休闲体育专业建设进行初步探讨。通过分析海南省体闲体育发展趋势特征,提出海南省高校休闲体育专业的人才培养目标、培养规格,课程体系设置和专业方向设置的建议;探讨在教育培养方案、专业课程知识体系、专业教材和教师方面的制约瓶颈,以期望海南高校为国际旅游岛休闲体育产业培养相关优秀的专业人才。  相似文献   
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