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861.
Abstract

The 2011 American Library Association conference took place June 23–28 at the Morial Convention Center in New Orleans, Louisiana. This report summarizes several programs and forums including the Association for Library Collections and Technical Services (ALCTS) Continuing Resources Section, Electronic Resources Interest Group program; Holdings Forum: Universal and Repurposed Holdings Information: Emerging Initiatives and Projects; the RDA Update Forum; and the Continuing Resources Cataloging Committee Update Forum.  相似文献   
862.
Medical and public health research often involve the analysis of repeated or longitudinal count data that exhibit excess zeros such as the number of yearly doctor visits by a group of individuals over a number of years. Zero-inflated Poisson (ZIP) regression models can be used to account for excess zeros in count data. We propose an extension of the ZIP model that is appropriate for longitudinal data. Our extension includes a non stationary, observation-driven time series model based correlation structure. We discuss estimation of the model parameters and the inefficiency of the estimators when the correlation structure is mis-specified. The model's application to the analysis of health care utilization data is also discussed.  相似文献   
863.
Franklin and Wasserman (1991) introduced the use of Bootstrap sampling procedures for deriving nonparametric confidence intervals for the process capability index, Cpk, which are applicable for instances when at least twenty data points are available. This represents a significant reduction in the usually recommended sample requirement of 100 observations (see Gunther 1989). To facilitate and encourage the use of these procedures. a FORTRAN program is provided for computation of confidence intervals for Cpk. Three methods are provided for this calculation including the standard method, the percentile confidence interval, and the biased - corrected percentile confidence interval.  相似文献   
864.
The purpose of this paper is to present some alternative estimates for the 'most probable number' of bacteria in a serial dilution experiment. These estimates are directed to be less biased than the ordinary maximum likelihood estimate. A numerical example illustrates the extent to which the variance and the mean square error of these estimates are generally less than those corresponding to the maximum likelihood estimate.  相似文献   
865.
The cause-of-death test of Peto et al.(1980)pools information from a Hoel-Walburg test on incidental tumors with information from a logrank test on fatal tumors in order to compare the tumor rate of a group of rodents exposed to a carcinogen against the tumor rate of a group of unexposed animals. The cause-of-death test, which can arise as a partial likelihood score test from a model that assumes proportional odds for tumor prevalence and proportional hazards for tumor mortality, is not, in general, a direct test for equality of tumor onset distributions for occult tumors that are observed in both fatal and incidental contexts. This paper develops a direct cause-of-death test for comparing distributions of time to onset of occultumors. The test is derived as a partial likelihood score test under an assumed proportional hazards model for tumor onset distributions. The size and power of the proposed test are compared in a Monte Carlo simulation study to the size and power of competitive procedures, including procedures that do not require cause-of-death information.  相似文献   
866.
As most market transactions involved the extension of informal credit because of a lack of ready cash, this meant that interpersonal trust was of central importance, and, as a result, a reputation for honesty and fair dealing in the community was vital to being successful. Money was used only in a limited number of exchanges, and credit, in the form of household reputation, was a “cultural currency” of trust used to transact most business. Trust, belief, and credit all went together, and no distinction was made between economic and social credit, as credit produced wealth and status of the middling sort. As the market expanded in the late sixteenth century, networks of credit became more intertwined over longer geographical distances, and thus trust became more problematic, and disputes over debts led to contention. These produced an enormous amount of litigation as the common law was increasingly used to enforce contracts. This led to much downward mobility through over-indebtedness, which reinforced the social importance of having good credit, and consequently the culture of credit became increasingly legalised. Although competition for credit together with the need to maintain household profitability put stress on the social maintenance of trust in the market, the economy could not work without it. As a result, the increase in commerce was seen as an essentially sociable activity because it required trust. Trust gradually came to be interpreted as the basis of justice, and the necessity of keeping promises, as the foundation of all social organisation. But by 1750 litigation had collapsed to a very low level, and self- control and politeness on the part of rational individuals came to play a more important role in dispute settlement than legal means. Whereas in the early modern period conflict occurred and was dealt with after its occurrence, self-control aimed to prevent inter-personal conflict and litigation before they happened. As a result, the concepts of “capital” and “savings” developed in the eighteenth century, and the structure of credit networks was changed.  相似文献   
867.
Over the past two decades the link – perceived and actual – between political extremism and football fans has been the subject of academic, political, and policing debate. It is not rare to witness manifestations of intolerance and ideological statements referring to regional, national and international issues at football stadia. In Italian football stadia, political representation has been evident for decades; politics has been integral to all realms of Italian society and culture since the origin of the nation. As one of the most significant Italian cultural practices, football has not been an exception. This combination of theory and action inspires thousands of young male football supporters. The football stadium might thus be interpreted as a twenty-first century social Agorá, where political opinions – otherwise ghettoized in society – can be freely expressed in pursuit of a wider consensus. This paper explores the under-researched milieu of neo-fascist ideology as displayed in contemporary Italian football stadia. Contributing original material and employing as conceptual frameworks the New Consensus Theory on fascism and the works of Julius Evola and Georges Sorel, this analysis hypothesizes that the neo-fascist tenets manifested by the ideologically-oriented ‘ultras’ fan groups, may be understood as both a consequence of, and a resistance against the dominant socio-cultural and political values of contemporary Italy. The research conducted between 2003–2007 sought to evaluate two internationally renowned ultras groups located in the Italian capital of Rome: the Boys of AS Roma and the Irriducibili of SS Lazio who enact their performances on their respective ‘curve’ [football terraces] of the city's Olympic stadium. Utilizing the ethnographic method, unique access was achieved in a notoriously difficult research milieu bringing the researcher into the social-cultural world of the participants and to the echelons of the extra-parliamentary Italian far right. Research sought to uncover the groups’ social interactions, values, and political beliefs, as a way of contributing to an understanding of both the Italian ultras of the twenty-first century and indeed the wider political milieu of the modern nation-state of Italy.  相似文献   
868.
In recent years, the United States, along with many other countries, has significantly increased its detection and defense mechanisms against terrorist attacks. A potential attack with a nuclear weapon, using nuclear materials smuggled into the country, has been identified as a particularly grave threat. The system for detecting illicit nuclear materials that is currently in place at U.S. ports of entry relies heavily on passive radiation detectors and a risk-scoring approach using the automated targeting system (ATS). In this article we analyze this existing inspection system and demonstrate its performance for several smuggling scenarios. We provide evidence that the current inspection system is inherently incapable of reliably detecting sophisticated smuggling attempts that use small quantities of well-shielded nuclear material. To counter the weaknesses of the current ATS-based inspection system, we propose two new inspection systems: the hardness control system (HCS) and the hybrid inspection system (HYB). The HCS uses radiography information to classify incoming containers based on their cargo content into "hard" or "soft" containers, which then go through different inspection treatment. The HYB combines the radiography information with the intelligence information from the ATS. We compare and contrast the relative performance of these two new inspection systems with the existing ATS-based system. Our studies indicate that the HCS and HYB policies outperform the ATS-based policy for a wide range of realistic smuggling scenarios. We also examine the impact of changes in adversary behavior on the new inspection systems and find that they effectively preclude strategic gaming behavior of the adversary.  相似文献   
869.
In recent years, the chemical and pharmaceutical industries have observed a noticeable decline in economic activity. This has resulted in many companies focusing on innovative research and development as they consider this key to business success. In particular, a number of leading industrial organisations have adopted the principles of Whole Process Design (WPD). WPD considers the optimisation of the entire product development process, from raw materials to end product, rather than focusing on each individual unit operation. The complexity involved with the implementation of WPD requires rationalised decision-making, often with limited or uncertain information. This paper presents the outcomes of two questionnaires that examined the requirements of professionals working within the chemistry-using industries with respect to developing a decision-making support tool. From the findings a methodology is proposed, the outcome of which allows a decision-maker to visually interpret their decision results with associated levels of uncertainty. A chemical route selection case study demonstrates and validates the application of the proposed methodology.  相似文献   
870.
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