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921.
Between 1974 and 1988, executives of DuPont, the world's largest producer of CFCs, were confronted with emerging evidence that CFCs were destroying the stratospheric ozone layer. The difficulty that executives face in such cases is that scientific knowledge develops over time and does not necessarily proceed in a straight line toward true conclusions. At the beginning of a new field of research, there is much uncertainty and disagreement among the experts. The solution of the ozone problem required a remarkable cooperation among science, business, and international governments. After looking at the role of DuPont executives in this drama, and the difficulties facing any executive dealing with uncertain science, the paper turns to an evaluation of the field of Business Ethics to see what light it might throw on this and analogous problems. Finally, the paper offers specific suggestions in terms of principles in dealing with uncertain science, and concludes that the course of action that DuPont followed, including some mistakes, can serve as a model for analogous crises.  相似文献   
922.
923.
H. Toutenburg  Shalabh 《Metrika》2002,54(3):247-259
This article considers a linear regression model with some missing observations on the response variable and presents two estimators of regression coefficients employing the approach of minimum risk estimation. Small disturbance asymptotic properties of these estimators along with the traditional unbiased estimator are analyzed and conditions, that are easy to check in practice, for the superiority of one estimator over the other are derived. Received May 2001  相似文献   
924.
Initial margin requirements represent: (1) a cost impediment to the wealth constrained investor and (2) a potential way of mitigating excessive volatility. However, prior empirical research finds that margins are not an effective tool in reducing volatility. We consider the possibility that margins primarily affect certain stocks and investors. Specifically, we test whether margins affect individuals who, as a group, we believe to be the investors most affected when margin requirements change. Our initial empirical tests, however, do not support this contention.  相似文献   
925.
A conceptual framework for evaluating statutory performance indicators for local authorities is developed. The framework, which contains 14 dimensions of organizational performance, is then applied to the indicators set for local government from 1993/94 to 2001/02. The results show that the validity and comparability of the indicators has improved substantially over time. However, a critical weakness that remains is the absence of indicators that link spending with service outcomes. Such indicators are essential if judgements about value for money and Best Value are to be made.  相似文献   
926.
Finance theory proposes that firms' cost of capital increases when market makers set wider spreads due to perceived higher information asymmetry across traders. Using a sample of UK investment property firms and controlling for firms' non-random selection of external monitors, we find evidence that market makers perceive information asymmetry across traders to be lower for firms employing external appraisers versus those employing internal appraisers. This evidence is consistent with liquidity-motivated traders being unable to overcome such reliability differences using asset value information from sources other than accounting. We fail to find a similar difference for firms employing Big 6 versus non-Big 6 auditors. Our findings contribute to the debate over the recognition of fair value estimates for long-lived tangible assets by documenting that reliability differences attributable to differential monitoring by appraisers can affect information asymmetry, and therefore firms' cost of capital.  相似文献   
927.
This paper examines Britain's long run growth and productivity performance since the late nineteenth century, taking an international comparative perspective and disaggregating by sector. Britain was richer than the United States and Germany in 1870 largely because of high levels of labour productivity in services and agriculture rather than in industry, together with a highly favourable structure, particularly a small share of the labour force in agriculture. By 1990, the productivity gap in manufacturing had not grown bigger. Rather, the deterioration in Britain's overall comparative labour productivity position has been concentrated in services and agriculture, together with the effects of structural change, particularly the later shift of labour out of agriculture in the United States and Germany.  相似文献   
928.
It is argued that insustrial policy for Eastern Europe is needed in order to reduce the social cost of transition. The industrial policy suggestes is based on unbalanced growth focused on key sectors that, according to linkage analysis, influence the economy more than other sector. An attempt should be made to increase efficency in key sectors, either by new investment or by closing down inefficient enterprises. This strategy could be adopted temporarily, gradually to move away from the existing structure of the economy rather than to reinforce it. In order to illustrate the potential of such an industrial policy, a sector-specific approach has been simulated for Poland using a compuable general equilibuium (CGE) model. The simulation results have shown that macroenonomic performance, measured by output, employment and funds available for invesment, is much better when industrial policy has been concentrated on a key sector.  相似文献   
929.
930.
Modeling the day-of-the-week shopping activity and travel patterns   总被引:1,自引:0,他引:1  
Dae-Sic Yun  M.E. O'Kelly 《Socio》1997,31(4):307-319
This research develops models that extend existing multi-day analyses of shopping activity patterns. The main hypothesis is that shopping activity choice behavior varies, depending on the day of the week. Using a nested logit model structure, this hypothesis is tested by developing models of daily activity choice behavior for each day of the week. In doing so, household activity choice behavior is represented by three stages, with a shopping activity participation decision as the highest stage, the scheduling decision as the next lower stage, and the number of shopping stops as the lowest stage. Empirical results confirm the nested logit model structure hypothesized in this study. Furthermore, it is found that major distinctions in the daily utility functions take place between the weekday and weekend models. However, differences among weekday models are also observed. This indicates that there appear to be behavioral differences even among weekdays although households are exposed to the same set of temporal constraints.  相似文献   
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