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111.
The possibility that carbon dioxide emissions from fossil fuel use might lead to global warming has become a leading environmental concern. Many scientific and environmental organizations have called for immediate action to limit carbon dioxide production. For the most part, however, public debate has focused on a single policy instrument: a carbon tax applied to fossil fuels in proportion to their carbon content. We present a detailed model of the U.S. economy and use it to compare carbon taxes with two other instruments that could achieve the same reduction in carbon dioxide emissions: a tax on the energy content of fossil fuels (a BTU tax) and an ad valorem tax on fuel use. We find that carbon taxes can achieve a given reduction with the least overall effect on the economy, but with a large effect on coal mining. Energy taxes are fairly similar to carbon taxes but have slightly less impact on coal mining and slightly greater overall cost. In contrast, ad valorem taxes fall much more lightly on coal mining but have a much greater effect on the economy as a whole.  相似文献   
112.
Five macroeconomic concepts are presented which are prominent in the business sections of newspapers, but which are not given equivalent prominence in macroeconomic textbooks. These are the discouraged worker phenomenon, the use of inventories in forecasting, the effect of changes in the money supply on the bond market, and the effects of inflation and nominal interest rates in the foreign exchange market. These concepts are presented via news clips illustrating the way they typically appear in the press. Instructors are urged to place extra emphasis on these concepts.  相似文献   
113.
114.
Recent studies have attempted to understand the processes involved in joint attention because of its relevance to both atypical and normal development. Data from a recent study of young children with autism suggests that performance on a delay nonmatch to sample (DNMS) task associated with ventromedial prefrontal functions, but not an A‐not‐B/delayed response task associated with dorsolateral prefrontal cortex, was related to joint attention skills (Dawson et al., 2002). Recent research also suggests that joint attention is associated with dorsalmedial brain systems linked to self‐monitoring (Mundy, 2003). This study investigated the relations among joint attention, DNMS, and self‐recognition performance in a longitudinal study of 39 normally developing toddlers from 14 to 18 months. The results indicated that development on the DNMS and self‐recognition tasks, but not a means end task, predicted joint attention at 18 months. Further analysis showed that the model was only significant for initiating joint attention (IJA). The implications of these results for the neuro‐development of IJA are discussed.  相似文献   
115.
Supporting processes of belonging in supervision and coachingThe contemporary employee has to cope with frequent changes. Not only does he lose his familiar environment, he also has to find ways to familiarize himself with new places and to develop a fresh sense of belonging. This process can be understood and facilitated by interpreting the German concept of “Heimat“ as something we have to create ourselves. First experiences demonstrate the usefulness of this approach in coaching processes.  相似文献   
116.
In this paper, the task of determining expected values of sample moments, where the sample members have been selected based on noisy information, is considered. This task is a recurring problem in the theory of evolution strategies. Exact expressions for expected values of sums of products of concomitants of selected order statistics are derived. Then, using Edgeworth and Cornish-Fisher approximations, explicit results that depend on coefficients that can be determined numerically are obtained. While the results are exact only for normal populations, it is shown experimentally that including skewness and kurtosis in the calculations can yield greatly improved results for other distributions.  相似文献   
117.
We consider the problem of estimating the scale parameter of an exponential or a gamma distribution under squared error loss when the scale parameter θ is known to be greater than some fixed value θ0. Natural estimators in this setting include truncated linear functions of the sufficient statistic. Such estimators are typically inadmissible, but explicit improvements seem difficult to find. Some are presented here. A particularly interesting finding is that estimators which are admissible in the untruncated problem which take values only in the interior of the truncated parameter space are found to be inadmissible for the truncated problem.  相似文献   
118.
The authors examined nineteen nonprofit performing arts organizations, investigating the distribution of influence among organizational members, the grouping of volunteers and staff in organizational structures, and the effectiveness of the organizations. The organizations' effectiveness was assessed using multiple performance indicators. The analysis revealed five groupings or configurations of influence, which correlated to the organizations exhibiting the highest and lowest levels of organizational effectiveness. The authors conclude that a variety of structures are associated with good performance but structural dysfunctions are associated with organizational failure, and that members' commitment to an organization's structure is an important element of success.  相似文献   
119.
Retrospective on the utility theory of von Neumann and Morgenstern   总被引:2,自引:0,他引:2  
This article offers an exegesis of the passages in von Neumann and Morgenstern (1944, 1947, 1953) that discuss their conception of utility. It is occasioned by two factors. First, as we approach the semicentennial of the publication of Theory of Games and Economic Behavior, its immense impact on economic thought in the intervening years encourages serious reflection on its authors' ideas. Second, misleading statements about the theory continue to appear. The article will have accomplished its purpose if it helps others appreciate the genius and spirit of the theory of utility fashioned by John von Neumann and Oskar Morgenstern.  相似文献   
120.
This investigation attempts to measure the relative influence of peer and parental influence on the perceived life satisfaction of two groups of secondary students in Hong Kong. Data on 1906 students from 30 schools were collected through the use of a self-administered questionnaire. Respondents were asked to rate their level of satisfaction on 26 different domains of life on a seven-point scale, ranging from very satisfied to very dissatisfied, as well as their satisfaction with life in general. These 26 items were combined to form six summary indices of life satisfaction: school life, family life, acceptance by others, government, media, and living environment. Two independent variables were used in the analysis of life satisfaction: peer orientation, and parent orientation. Both are composite indices and measure the adolescent's attachment to and identification with his peers or parents. It was found that parent orientation is a better predictor of life satisfaction than peer orientation. Adolescents who are high on parent orientation are more satisfied with every domain of life. They are also more satisfied with life in general. The relationship between peer orientation and life satisfaction is not a clear-cut one. Adolescents with strong peer orientation are more satisfied with school, media, government, and acceptance by others, but are less satisfied with family. There is no significant relationship between peer orientation and environment. The younger adolescents in our sample tend to perceive a higher level of satisfaction than the older adolescents in every domain of life as well as life in general.  相似文献   
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