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271.
Terrorist actions are aimed at maximizing harm (health, psychological, economical, and political) through the combined physical impacts of the act and fear. Immediate and effective response to a terrorist act is critical to limit human and environmental harm, effectively restore facility function, and maintain public confidence. Though there have been terrorist attacks in public facilities that we have learned from, overall our experiences in restoration of public facilities following a terrorist attack are limited. Restoration of public facilities following a release of a hazardous material is inherently far more complex than in industrial settings and has many unique technical, economic, social, and political challenges. For example, there may be a great need to quickly restore the facility to full operation and allow public access even though it was not designed for easy or rapid restoration, and critical information is needed for quantitative risk assessment and effective restoration must be anticipated to be incomplete and uncertain. Whereas present planning documents have substantial linearity in their organization, the “adaptive management” paradigm provides a constructive parallel paradigm for restoration of public facilities that anticipates and plans for uncertainty, inefficiencies, and stakeholder participation. Adaptive management grew out of the need to manage and restore natural resources in highly complex and changing environments with limited knowledge about causal relationships and responses to restoration actions. Similarities between natural resource management and restoration of a public facility after a terrorist attack suggest that integration of adaptive management principles explicitly into restoration processes will result in substantially enhanced and flexible responses necessary to meet the uncertainties of potential terrorist attacks. 相似文献
272.
The training of medical practitioners to improve the practitioner/patient relationship may be difficult, as limitations often exist on the choice of patients included in the study. A specific study of this type of training is given. It is proposed that a simple modification and generalization of Yates' plaid-square designs be used. It is shown that a replicated plaid-design incorporates as a special case the criss-cross or strip-plot design. The usefulness of these designs in studies of the training of medical practitioners is illustrated. The basic characteristics of their analysis are outlined. 相似文献
273.
274.
Sets of alternatives as Condorcet winners 总被引:1,自引:0,他引:1
We characterize sets of alternatives which are Condorcet winners according to preferences over sets of alternatives, in terms
of properties defined on preferences over alternatives. We state our results under certain preference extension axioms which,
at any preference profile over alternatives, give the list of admissible preference profiles over sets of alternatives. It
turns out to be that requiring from a set to be a Condorcet winner at every admissible preference profile is too demanding,
even when the set of admissible preference profiles is fairly narrow. However, weakening this requirement to being a Condorcet
winner at some admissible preference profile opens the door to more permissive results and we characterize these sets by using
various versions of an undomination condition. Although our main results are given for a world where any two sets – whether
they are of the same cardinality or not – can be compared, the case for sets of equal cardinality is also considered.
Received: 15 March 2001/Accepted: 31 May 2002
This paper was written while Barış Kaymak was a graduate student in Economics at Boğazi?i University. We thank ?ağatay Kayı
and İpek ?zkal-Sanver who kindly agreed to be our initial listeners. The paper has been presented at the Economic Theory seminars
of Bilkent, Ko? and Sabancı Universities as well as at the Fifth Conference of the Society for the Advancement of Economic
Theory, July 2001, Ischia, Italy and at the 24th Bosphorus Workshop on Economic Design, August 2001, Bodrum, Turkey. We thank Fuad Aleskerov, İzak Atiyas, ?zgür Kıbrıs, Semih
Koray, Gilbert Laffond, Bezalel Peleg, Murat Sertel, Tayfun S?nmez, Utku ünver and all the participants. Remzi Sanver acknowledges
partial financial support from İstanbul Bilgi University and the Turkish Academy of Sciences and thanks Haluk Sanver and Serem
Ltd. for their continuous moral and financial support. Last but not the least, we thank Carmen Herrero and two anonymous referees.
Of course we are the sole responsible for all possible errors. 相似文献
275.
To reduce nonresponse bias in sample surveys, a method of nonresponse weighting adjustment is often used which consists of multiplying the sampling weight of the respondent by the inverse of the estimated response probability. The authors examine the asymptotic properties of this estimator. They prove that it is generally more efficient than an estimator which uses the true response probability, provided that the parameters which govern this probability are estimated by maximum likelihood. The authors discuss variance estimation methods that account for the effect of using the estimated response probability; they compare their performances in a small simulation study. They also discuss extensions to the regression estimator. 相似文献
276.
277.
Micro‐enterprises, i.e. firms with less than 10 employees, are traditionally the hardest to engage in learning; they are also least likely to participate in such measures as business advice and guidance provision and initiatives to support information communication technology (ICT) adoption. Through a community‐based initiative initially targeting parents (unemployed or employed) to participate in ICT, 30 micro‐enterprises were attracted to learning for the first time. These companies had carefully avoided similar initiatives taking place locally, which emphasized business success and growth; they had only participated in this ICT skills training because of their children. The paper takes a case study approach to evaluate the reasons for participation, explores barriers and implications for those organizing similar activities, and calls for a more holistic view of owners and managers of small firms as fathers, mothers, etc. rather than just as ‘entrepreneurs’. 相似文献
278.
279.
James P. McDermott G. Jogesh Babu John C. Liechty Dennis K. J. Lin 《Statistics and Computing》2007,17(4):311-321
We consider the problem of density estimation when the data is in the form of a continuous stream with no fixed length. In
this setting, implementations of the usual methods of density estimation such as kernel density estimation are problematic.
We propose a method of density estimation for massive datasets that is based upon taking the derivative of a smooth curve
that has been fit through a set of quantile estimates. To achieve this, a low-storage, single-pass, sequential method is proposed
for simultaneous estimation of multiple quantiles for massive datasets that form the basis of this method of density estimation.
For comparison, we also consider a sequential kernel density estimator. The proposed methods are shown through simulation
study to perform well and to have several distinct advantages over existing methods. 相似文献
280.