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41.
The goal of Louisiana's 1990–1991 comparative risk project, also called the Louisiana Environmental Action Plan (LEAP), was to incorporate risk assessment into state environmental planning and policymaking. Scientists, government officials, and citizens were brought together to estimate the relative risk to human health, natural resources, and quality of life posed by 33 selected environmental issues. The issues were then ranked according to their relative estimated risks. It was hoped that this ranking of "comparative risks" would enable state policymakers to target the most important environmental problems and allocate scarce public resources more rationally and efficiently. As a result of the project, the governor issued an Executive Order forming a permanent Public Advisory Committee to continue this type of comparative risk assessment in Louisiana.  相似文献   
42.
This is an analysis of the social context of normal police lies. We define lies as speech acts which the speaker knows are misleading or false, are intended to deceive, and where evidence to the contrary is known to the observer. Lies are relative to a moral context, and what an audience will accept. Lies include excuses, which deny full responsibility for an act, but acknowledge its immorality, and justifications, which accept responsibility but deny blame-worthiness. Police learn to lie and to carefully distinguish normal (or acceptable) lies from unacceptable lies, suggesting that lies are a part of a negotiated occupational order. We show how and why some types of lies are rewarded by police using ethnographic data from an 18 month field study of a large urban force. Lies can be of little issue, or become troublesome. We report and analyze two kinds of troublesome lies: case lies, recognized stories an officer utilizes in a courtroom or on paper to facilitate the conviction of a suspect, and cover stories, lies an officer tells in court, to supervisors, and on the job with the aim of providing a verbal shield or mitigation in the event of discipline. Both excuses and justifications are woven together in these vignettes. An example of a refusal to lie is used to illustrate some of the limits on lying as well organizational factors in lying. Some implications for official lying are also noted.  相似文献   
43.
Summary.  To help to design vaccines for acquired immune deficiency syndrome that protect broadly against many genetic variants of the human immunodeficiency virus, the mutation rates at 118 positions in HIV amino-acid sequences of subtype C versus those of subtype B were compared. The false discovery rate (FDR) multiple-comparisons procedure can be used to determine statistical significance. When the test statistics have discrete distributions, the FDR procedure can be made more powerful by a simple modification. The paper develops a modified FDR procedure for discrete data and applies it to the human immunodeficiency virus data. The new procedure detects 15 positions with significantly different mutation rates compared with 11 that are detected by the original FDR method. Simulations delineate conditions under which the modified FDR procedure confers large gains in power over the original technique. In general FDR adjustment methods can be improved for discrete data by incorporating the modification proposed.  相似文献   
44.
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   
45.
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   
46.
47.
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   
48.
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   
49.
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   
50.
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   
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