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This study analyzes the effects of an important postderegulation innovation on rail freight productivity: the elimination of cabooses and related crew members. It also analyzes the overall growth of productivity in rail freight between 1983 and 1997 (using a translog rail cost function estimated over a sample of Class I railroads between 1983 and 1997). The results indicate that elimination of cabooses and associated crew members from freight trains reduced costs by 5-8% on the typical Class I railroad in 1997, equivalent to an annual cost saving of $2 billion to $3.3 billion for all Class I railroads. Moreover, if Class I railroads had no other technological advances since 1983, their 1997 costs (with 1997 factor prices) would have been 36-43% higher than they in fact were. Finally, the results show that overall productivity growth in rail freight did not decelerate between 1983 and 1997; if anything, it accelerated slightly.  相似文献   
444.
A Product and Process Model of the Technology-Sourcing Decision   总被引:1,自引:0,他引:1  
The technology‐sourcing decision traditionally has examined the choice either to innovate internally or to acquire technology from outside sources. The increasing complexity of this decision requires a move beyond the simple “make‐versus‐buy” dichotomy. We seek to test factors that influence the technology decision of subsidiaries for product and process technology across the continuum of options from internal development to outsourcing. We also explore concordance between the research streams of new product development and technology sourcing. Regression models are used to analyze data from 187 subsidiaries that suggest product and process technology development decisions sometimes are associated with similar factors and at other times they diverge. In particular, we find that external product and process technology acquisition decisions are associated negatively with differentiation goals and associated positively with product dynamism. While external product acquisition is associated negatively with a low cost goal and positively with increasing distance between primary marketing and R&D operations, external process technology acquisition is associated positively with high competitive intensity. Implications include the following: (1) While external product technology acquisition may provide quicker or even less expensive initial solutions, external reliance makes it difficult to maintain a long‐term positional advantage; (2) When greater distances separate key functional activities, external partners may provide solutions that are more responsive to local consumer needs, and the potential for improved communication may allow for quicker adaptation and increased flexibility; (3) In highly dynamic product situations, internal development, while providing greater control, can be expensive and can result in technologies that are not accepted by the marketplace; and (4) As competitive intensity increases, strategic imperatives may reduce the focus on product design and development and may require increasing concentration on manufacturing costs and efficiencies.  相似文献   
445.
The paper asks the question – as time series analysis moves from consideration of conditional mean values and variances to unconditional distributions, do some of the familiar concepts devised for the first two moments continue to be helpful in the more general area? Most seem to generalize fairly easy, such as the concepts of breaks, seasonality, trends and regime switching. Forecasting is more difficult, as forecasts become distributions, as do forecast errors. Persistence can be defined and also common factors by using the idea of a copula. Aggregation is more difficult but causality and controllability can be defined. The study of the time series of quantiles becomes more relevant.  相似文献   
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Two of the main forces driving European emigration in the late nineteenth century were real wage gaps between sending and receiving regions and demographic booms in the low‐wage sending regions. Our new estimates of net migration for the countries of sub‐Saharan Africa show that exactly the same forces driving African across‐border migration are at work today. The results suggest that rapid growth in the cohort of potential young emigrants, population pressure on the resource base, and slow economic growth are likely to intensify the pressure for migration out of Africa and into high‐wage OECD countries over the next two decades.  相似文献   
448.
In this study I investigate the relation between firm‐level insider‐trading restrictions and executive compensation. Using a trading‐window proxy for the existence of such restrictions, I test predictions that insiders will demand compensation for these restrictions and that firms will need to increase incentives to restricted insiders. I find that firms that restrict insider trading pay a premium in total compensation relative to firms not restricting insider trading, after controlling for economic determinants of pay. Furthermore, these firms use more incentive‐based compensation and their insiders hold larger equity incentives relative to firms that do not restrict insider trading. These results hold after controlling for the endogenous decision to restrict insiders and are consistent with the notion that insider trading plays a role in rewarding and motivating executives.  相似文献   
449.
Linear predictability of stock market returns has been widely reported. However, recently developed theoretical research has suggested that due to the interaction of noise and arbitrage traders, stock returns are inherently non‐linear, whereby market dynamics differ between small and large returns. This paper examines whether an exponential smooth transition threshold model, which is capable of capturing this non‐linear behaviour, can provide a better characterization of UK stock market returns than either a linear model or an alternate non‐linear model. The results of both in‐sample and out‐of‐sample specification tests support the exponential smooth transition threshold model and hence the belief that investor behaviour does differ between large and small returns.  相似文献   
450.
K.S. Larsen 《Futures》2003,35(2):163-167
Relations between rich and poor (across and within countries) appeared in some questions in Images; there were clear differences between what the powerful and the powerless hoped and expected from the future. This is compared with what actually happened and a deeper analysis is made of ‘power’ as an organizing concept. It turned out that the pessimism associated with powerlessness tended to make better predictions.  相似文献   
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