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71.
We address the problem of distributing safety-enhancing devices across a region, where each identical device provides for only local protection of the population. The devices protect nonidentical sectors of the population. The sectors of population are exposed to nonidentical intensities of hazard. A method for the screening and prioritizing of needs for the protective devices is described. An approach of risk-benefit-cost analysis under uncertainty is recommended as follows. Measures of hazard intensity and population exposure are identified. Exogenous parameters that influence assessments of risks, benefits, and costs are identified. Uncertainties of the exogenous parameters are propagated by interval analysis. Several tiers of the plausibility of need for protection are identified. The tiers are useful in setting priorities for the distribution of the safety devices. The method is demonstrated in an engineering application to roadway lighting, but has implications for disaster preparedness, anti-terrorism, transportation safety, and other arenas of public safety. 相似文献
72.
Combining Food Frequency and Survey Data to Quantify Long-Term Dietary Exposure: A Methyl Mercury Case Study 总被引:2,自引:0,他引:2
Twenty-four-hour recall data from the Continuing Survey of Food Intake by Individuals (CSFII) are frequently used to estimate dietary exposure for risk assessment. Food frequency questionnaires are traditional instruments of epidemiological research; however, their application in dietary exposure and risk assessment has been limited. This article presents a probabilistic method of bridging the National Health and Nutrition Examination Survey (NHANES) food frequency and the CSFII data to estimate longitudinal (usual) intake, using a case study of seafood mercury exposures for two population subgroups (females 16 to 49 years and children 1 to 5 years). Two hundred forty-nine CSFII food codes were mapped into 28 NHANES fish/shellfish categories. FDA and state/local seafood mercury data were used. A uniform distribution with minimum and maximum blood-diet ratios of 0.66 to 1.07 was assumed. A probabilistic assessment was conducted to estimate distributions of individual 30-day average daily fish/shellfish intakes, methyl mercury exposure, and blood levels. The upper percentile estimates of fish and shellfish intakes based on the 30-day daily averages were lower than those based on two- and three-day daily averages. These results support previous findings that distributions of "usual" intakes based on a small number of consumption days provide overestimates in the upper percentiles. About 10% of the females (16 to 49 years) and children (1 to 5 years) may be exposed to mercury levels above the EPA's RfD. The predicted 75th and 90th percentile blood mercury levels for the females in the 16-to-49-year group were similar to those reported by NHANES. The predicted 90th percentile blood mercury levels for children in the 1-to-5-year subgroup was similar to NHANES and the 75th percentile estimates were slightly above the NHANES. 相似文献
73.
This paper presents a conceptual model for the creation and operation of supply networks. Existing conceptual research relating to interorganizational relationships and networks is reviewed in terms of its relevance to understanding supply networks; this research is drawn from the fields of strategic management, channel management, industrial marketing and purchasing, organizational behaviour and supply‐chain management. The different perspectives each field has on networks are highlighted. Contributions made by each in assisting to understand supply networks are discussed and synthesized. Findings from an exploratory survey are used to structure the design of a conceptual model for analysing the processes involved in the creation and operation of supply networks. The authors identify nine different types of networking activities and discuss the nature of these activities in the context of supply. Four different types of contextual factors relating to supply networks are identified. The model is tested in eight in‐depth case studies and a validating survey of 58 focal firm networks. It is concluded that it provides a robust structure that enabled complex, cross‐case analysis of multi‐variable, multi‐disciplinary data from interorganization product/service supply networks, but that further testing by other researchers is required. 相似文献
74.
Jean‐Yves Duclos Joan Esteban Debraj Ray 《Econometrica : journal of the Econometric Society》2004,72(6):1737-1772
We develop the measurement theory of polarization for the case in which income distributions can be described using density functions. The main theorem uniquely characterizes a class of polarization measures that fits into what we call the “identity‐alienation” framework, and simultanously satisfies a set of axioms. Second, we provide sample estimators of population polarization indices that can be used to compare polarization across time or entities. Distribution‐free statistical inference results are also used in order to ensure that the orderings of polarization across entities are not simply due to sampling noise. An illustration of the use of these tools using data from 21 countries shows that polarization and inequality orderings can often differ in practice. 相似文献
75.
On the correlation between fraud and default risk 总被引:1,自引:0,他引:1
Thomas Mählmann 《Zeitschrift für Betriebswirtschaft》2010,80(12):1325-1352
Identity fraud is one of the fastest growing white-collar crimes today and a serious concern in our information-based economy. This paper studies one type of identity fraud: new account fraud, where an impostor opens lines of credit using a false identity, made-up or stolen. Relying on a unique data set of consumer bank accounts, that contains information on both, fraud and default losses, I analyze the correlation between fraud and default risk. I find that common socio-economic/demographic account holder characteristics have opposite effects on estimated default and fraud probabilities. For example, women possess a lower fraud probability, but a higher default probability, compared to men, and foreigners are more likely to engage in account fraud but less likely to default than Germans. Also, the portfolio level analysis indicates that portfolio loss distributions are quite sensitive to ex ante portfolio characteristics like the share of foreigners or blue-collar workers. These findings have important implications for banks managing their consumer credit portfolios using limiting rules based on borrower characteristics, and for the adequacy of banks’ capital levels. 相似文献
76.
Prof. Dr. Thomas Rudolph Dipl.-Kfm. Johannes C. Bauer Prof. Dr. Winfried J. Steiner 《Zeitschrift für Betriebswirtschaft》2010,80(3):285-327
This article reviews published literature and provides an overview on present empirical evidence about the framing of price promotions. Concerning explicit price reductions (discounts, coupons, rebates), the effects of advertised reference prices and different frames of price discounts (relative versus absolute price discount, objective versus tensile price claims) on consumers’ reactions are discussed. Furthermore, the article examines empirical results on implicit price reductions (volume packs, free extra products) as well as on sale signs and restrictions (e.g. purchase limits, time limits) as popular ways of framing a deal. The key findings point out that framing a price promotion in different ways can affect consumers’ perceptions and evaluations of the deal. Based on the reviewed literature, the concluding section provides managerial implications and an agenda for further research. 相似文献
77.
Adiel T. De Almeida Filho Christophe Mues Lyn C. Thomas 《Production and Operations Management》2010,19(6):698-708
This paper builds a dynamic programming model to optimize the collections process in consumer credit. It determines which collections actions should be undertaken and how long they should be performed, including theoretical results about the form of the optimal policy under certain conditions. Finally, a case study is described based on data from the collections department of a European bank. 相似文献
78.
79.
Papen Marie-Christin Niemand Thomas Siems Florian U. Kraus Sascha 《Review of Managerial Science》2019,13(4):725-747
Review of Managerial Science - This article examines positive effects of customer stress drawn upon the theory of excitation transfer. Contrary to previous marketing and management literature, the... 相似文献
80.
Multimedia fate and exposure models are widely used to regulate the release of toxic chemicals, to set cleanup standards for contaminated sites, and to evaluate emissions in life-cycle assessment. CalTOX, one of these models, is used to calculate the potential dose, an outcome that is combined with the toxicity of the chemical to determine the Human Toxicity Potential (HTP), used to aggregate and compare emissions. The comprehensive assessment of the uncertainty in the potential dose calculation in this article serves to provide the information necessary to evaluate the reliability of decisions based on the HTP A framework for uncertainty analysis in multimedia risk assessment is proposed and evaluated with four types of uncertainty. Parameter uncertainty is assessed through Monte Carlo analysis. The variability in landscape parameters is assessed through a comparison of potential dose calculations for different regions in the United States. Decision rule uncertainty is explored through a comparison of the HTP values under open and closed system boundaries. Model uncertainty is evaluated through two case studies, one using alternative formulations for calculating the plant concentration and the other testing the steady state assumption for wet deposition. This investigation shows that steady state conditions for the removal of chemicals from the atmosphere are not appropriate and result in an underestimate of the potential dose for 25% of the 336 chemicals evaluated. 相似文献