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981.
This article presents an approach to the problem of terrorism risk assessment and management by adapting the framework of the risk filtering, ranking, and management method. The assessment is conducted at two levels: (1) the system level, and (2) the asset-specific level. The system-level risk assessment attempts to identify and prioritize critical infrastructures from an inventory of system assets. The definition of critical infrastructures offered by Presidential Decision Directive 63 was used to determine the set of attributes to identify critical assets--categorized according to national, regional, and local impact. An example application is demonstrated using information from the Federal Highway Administration National Bridge Inventory for the State of Virginia. Conversely, the asset-specific risk assessment performs an in-depth analysis of the threats and vulnerabilities of a specific critical infrastructure. An illustration is presented to offer some insights in risk scenario identification and prioritization, multiobjective evaluation of management options, and extreme-event analysis for critical infrastructure protection. 相似文献
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983.
We prove a lemma characterizing majority preferences over lotteries on a subset of Euclidean space. Assuming voters have quadratic von Neumann–Morgenstern utility representations, and assuming existence of a majority undominated (or “core”) point, the core voter is decisive: one lottery is majority-preferred to another if and only if this is the preference of the core voter. Several applications of this result to dynamic voting games are discussed.This paper was completed after Jeff Banks’s death. John Duggan is deeply indebted to him for his friendship and his collaboration on this and many other projects. 相似文献
984.
Objective. Smoking and obesity are associated with significant wage penalties when considered separately. We assess the combined effects of those behaviors. Methods. We estimate the effects of smoking and obesity on wages using multivariate regression analysis with 1979 National Longitudinal Survey of Youth data. Results. The raw data indicate that obese smokers experience large earnings penalties. However, these penalties are not found to be interactive or directly causal for most of the demographic subgroups we examine. One exception is the wage penalty associated with obesity for females, which remains significant throughout the analysis. Conclusions. In the absence of a demonstrable direct causal effect of those behaviors on wages, associated individual‐specific socioeconomic factors appear to be the driving forces behind the obese smoker wage penalty. Not included, but potentially significant, are the effects of employer and customer discrimination against obese smokers and the possible labor policy implications of such discrimination. 相似文献
985.
School Size and the Interpersonal Side of Education: An Examination of Race/Ethnicity and Organizational Context* 总被引:1,自引:0,他引:1
Robert Crosnoe Monica Kirkpatrick Johnson Glen H. Elder 《Social science quarterly》2004,85(5):1259-1274
Objectives. The purpose of this study was to extend research on the connection between school size and student outcomes by examining how school size was related to interpersonal processes and whether the interpersonal effects of school size varied by race/ethnicity. Methods. We applied multilevel modeling techniques to a sample of 14,966 students in 84 schools from the National Longitudinal Study of Adolescent Health. Results. Increasing school size was associated with decreasing student attachment to school and to teachers as well as extracurricular participation. Student attachment and teacher bonding diminished with increasing school size at a decreasing rate (reaching minimums in schools with between 1,700–2,000 students), but extracurricular participation dropped at a steady rate. These patterns did not differ substantially by race/ethnicity. Conclusions. The size of the educational institution influences interpersonal dynamics among actors in the institution and does so similarly across student groups. More generally, this research demonstrates the importance of organizational characteristics for social life. 相似文献
986.
We introduce a number of new methods based on sequence analysis to test hypotheses on the de-standardization of family-life trajectories in early adulthood, using Fertility and Family Survey data on 19 countries. Across cohorts, family-life trajectories of young adults have not become more turbulent. However, in most countries family-life trajectories of young adults have become less similar to one another and the variation in the types of family-trajectories has increased. Contrary to expectations, no clear differences in de-standardization were observed between countries characterized by a social-democratic welfare-state regime and countries characterized by either liberal or conservative welfare-state regimes. 相似文献
987.
QUANTILES OF SUMS AND EXPECTED VALUES OF ORDERED SUMS 总被引:1,自引:0,他引:1
Watson & Gordon (1986) investigated the relationship between the quantiles of a sum of independent continuous random variables and the sum of the individual quantiles. In this note some further results are obtained. Also corresponding relationships are developed for the expected values of the order statistics of a sum, and for the sum of the expected values of the individual order statistics. 相似文献
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