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41.
In Stein's 1959 example, for any sample with n sufficiently large, there is a confidence set embedded simultaneously within two regular confidence belts—one with coverage frequency smaller than an arbitrary positive ϵ, the other with coverage frequency larger than 1 — ϵ. Thus, Stein's example may be seen as an extreme case of mutually conflicting confidence statements, illustrating a possibility anticipated and denounced by Fisher.  相似文献   
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A recent investigation of the British General Household Survey (GHS) found substantial over-reporting of childlessness in recent years, particularly at older ages. We examine the phenomenon in further detail and find that the principal cause was change in survey procedures. To some extent the bias can be corrected for by using information on own children in the household. Revised fertility histories give period estimates of total fertility that are in close agreement with national vital registration statistics, unlike those based on original fertility histories of recent years. Misreporting in fertility histories dates primarily from administrative changes in the GHS in the years 1998-2000, and particularly from 2003, when the option of laptop self-completion (CASI) was introduced for reporting demographic histories.  相似文献   
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This article identifies the most cohesive multi‐polar regions of the network of world cities, which differ from the unipolar centre–periphery model largely created by the high weight of central city connections. We use a community detection algorithm that outlines the high densities of city networks (in relative weights). Various patterns of industries and services, which are divided into two skill levels, are identified. We use a global database of the network of 1.2 million direct and indirect ownership links between the 800,000 subsidiaries of the top 3000 multinational groups in 2013, allowing us to build four comparable networks of 503 metropolitan areas. Comparing the obtained partitions with continental, regional and economic benchmarks, classes of cities partially correspond to free trade zones (FTZs) but exhibit interesting cross‐continental patterns. A few cities, changing their classes according to the activities, are discussed in the light of the multinational firms' strategies.  相似文献   
44.
Men who have sex with men (MSM) who attend group-sex events often engage in risky sexual behaviors that contribute to the high human immunodeficiency virus (HIV) incidence among this population. We conducted an online survey with 211 New York City MSM who attended sex parties in the prior year and asked them to describe their behaviors and perceptions of risk. We compared responses from HIV-positive-undetectable men (n = 36), HIV-negative men on pre-exposure prophylaxis (PrEP; n = 62), and HIV-negative men never on PrEP (n = 113). In bivariate analyses, undetectable and on-PrEP men had been to more sex parties in the prior six months, had more anal sex partners there, and had higher rates of sexually transmitted infection (STI) diagnoses than men never on PrEP. Although less than the other groups, 43% of the presumably HIV-negative men never on PrEP reported condomless anal sex at a party in the prior six months. About half of participants agreed that, at sex parties, they made assumptions about others’ HIV status, that they sometimes took more risks than intended, and that the atmosphere of these events was conducive to risk taking. Most disagreed that there was discussion of HIV status at sex parties. Implications for sexual health interventions are discussed.  相似文献   
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This article analyses how the Inter-American System for the protection of human rights has used ILO standards as a reference on matters relating to freedom of association and the rights of indigenous peoples. Having established the limits to their use, the authors also analyse how these standards have influenced recent Inter-American jurisprudence in relation to certain economic, social and cultural rights. They argue that such cross-referencing is both desirable and useful, since it allows the Inter-American bodies to base their arguments on the interpretation of specialized authorities, thereby reinforcing the credibility, normative legitimacy and universality of their decisions.  相似文献   
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Current factory design and evaluation is very primitive. Factory components are designed in many cases independently. Product and process design are not well integrated. An encompassing framework is needed for iterating through a series of total factory designs, searching for optimal performance. In addition, a vehicle is needed for predicting the performance of a proposed advanced manufacturing system, so that engineers may have a sound means for evaluating such proposals. A heterarchical discrete manufacturing SIMNET II simulation model (SIMCELLS) was developed as a comprehensive methodology for designing and evaluating discrete manufacturing systems. SIMCELLS allows manufacturing systems engineers to experiment with alternative system structures and control strategies while seeking that combination of design features that will produce the desired overall system performance. The model in combination with a modernization programme is enabling a firm to successfully manufacture and sell trucks meeting international standards. The SIMNET II model  相似文献   
50.
The just-in-time (JIT) system has been studied extensively and implemented by a number of US firms as an ell'ective production system. The core of JIT involves determination of lot size and setup time reduction so as to increase manufacturing flexibility while minimizing the inventory level. This decision problem usually involves multiple conflicting objectives and mixed-model production. In this paper, goal programming (GP) is applied to a real-world JIT problem involving fabrication of different automotive and industrial rubber composite belts. The model results provide new insights concerning the conflicting nature of several goals, especially between meeting demand and reducing setup or idle time. Also, the GP solution is superior to the current JIT practice of the company.  相似文献   
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