Trivial Two-Stage Group Testing with High Error Rates

Given a population of cardinality q ^r that contains a positive subset P of cardinality p, we give a trivial two-stage method that has first stage pools each of which contains q ^{r – 2} objects. We assume that errors occur in the first stage. We give an algorithm that uses the results of first stage to generate a set CP of candidate positives with |CP| (r + 1)q. We give the expected value of |CPP|. At most (r + 1)q trivial second stage tests are needed to identify all the positives in CP. We assume that the second stage tests are error free.     

关于“核心家庭”概念和“婚姻”定义的探讨－学术史回顾及摩梭走访制引发的思考

中国摩梭个案对于人类学家在婚姻与亲属领域的研究无疑具有重要意义,它已经引起了学者们的广泛关注.以下的文字节译自美籍华裔人类学家施传刚的博士论文<永宁摩梭中国西南一个异居制母系社会的性联盟、家户组织、文化性别与民族认同>(美国斯坦福大学,1993年).尽管它多半不是作者的结论而只是进一步研究的基础,然而,这段简明的学术史的述评性回顾可以让我们对国外同行在该研究领域里的历史状况有一个基本的了解.译文是原作第8章"两栖居、走访制、核心家庭以及婚姻的定义"内的两小节,大题目由译者拟制,两小节的标题则是原来有的.     

The Paradoxes of Modernity: Scientific Advances,Environmental Problems,and Risks to the Social Fabric?

Recent reviews have contrasted U.S. sociologists' empirical work on technological risks with the theoretical risk work of Giddens and Beck, but the reality is more complex. Most U.S. sociologists are less likely than Giddens or Beck to see risks as transcending socioeconomic and other divisions, but the United States–based work tends to interpret the trustworthiness of scientific–technical expertise in ways that lie between the arguments of Beck and Giddens. An examination of early nuclear technologies indicates that the United States–based perspectives provide a better fit, for theoretical as well as empirical reasons. The development of nuclear technologies was mixed, rather than high or low, in its competence and trustworthiness, and it created social and environmental risks that did not so much transcend social divisions as to reinforce them.     

Applications in business,medical and industrial statistics of bi-aspect nonparametric tests for location problems

Starting from the theory of the Nonparametric Combination of Dependent Permutation Tests (Pesarin, 1992, 2001), Marozzi (2002a, b) proposed two bi-aspect nonparametric tests for the two-sample and the multi-sample location problems. These tests are shown by simulation to be remarkably more powerful than the traditional parametric and permutation competitors (which can be seen as uni-aspect tests) under heavy-tailed and skewed distributions. After a brief presentation of the bi-aspect idea to location testing problems, three actual applications are discussed. The first one is a problem of business statistics and deals with the analysis of time for service calls. The second one is in medical statistics and deals with the analysis of the effect of cigarette smoking on maternal airway function during pregnancy. The third one is in industrial statistics and deals with the analysis of the setting of machines that produce steel ball bearings. The bi-aspect testing allows us to draw deeper and more informative inference than that allowed by traditional competitors.Marco Marozzi: Part of the research was done when the author was in Dipartimento di Scienze Statistiche, Universitá di Bologna, Italy.     

Variability of Site-Reactor Risk

Reactor accident consequence models have been developed (for example, the CRAC model of the Reactor Safety Study (RSS), WASH-1400) to predict the offsite health and economic consequences of severe accidents at a reactor site with generic demographic and meteorological characteristics. Application of a revised RSS accident consequence model, CRAC2, to 91 existing sites results in a band of risk curves around the earlier WASH-1400 average reactor/site predictions. This paper examines these calculations and important model assumptions such as population distribution, emergency response, and meteorological data with respect to their effects on site risk extremes—that is, the combination of high consequence/low probability events.     

Sensitivity and Uncertainty Studies of the CRAC2 Computer Code

We have studied the sensitivity of health impacts from nuclear reactor accidents, as predicted by the CRAC2 computer code, to the following sources of uncertainty: (1) the model for plume rise, (2) the model for wet deposition, (3) the meteorological bin-sampling procedure for selecting weather sequences with rain, (4) the dose conversion factors for inhalation as affected by uncertainties in the particle size of the carrier aerosol and the clearance rates of radionuclides from the respiratory tract, (5) the weathering half-time for external ground-surface exposure, and (6) the transfer coefficients for terrestrial foodchain pathways. Predicted health impacts usually showed little sensitivity to use of an alternative plume-rise model or a modified rain-bin structure in bin-sampling. Health impacts often were quite sensitive to use of an alternative wet-deposition model in single-trial runs with rain during plume passage, but were less sensitive to the model in bin-sampling runs. Uncertainties in the inhalation dose conversion factors had important effects on early injuries in single-trial runs. Latent cancer fatalities were moderately sensitive to uncertainties in the weathering half-time for ground-surface exposure, but showed little sensitivity to the transfer coefficients for terrestrial foodchain pathways. Sensitivities of CRAC2 predictions to uncertainties in the models and parameters also depended on the magnitude of the source term, and some of the effects on early health effects were comparable to those that were due only to selection of different sets of weather sequences in bin-sampling.     

Comparing the Fisher information in record data and random observations

We compare the Fisher information (FI) contained in the firstn record values and record times with the FI inn i. i. d. observations. General results are established for exponential family and Weibull type setups, and a summary table is provided listing several common distributions. We show that the FI in record data improves notably once the record times are included, often changing from being less to being equal or greater than the FI in a random sample of the same size. The behavior in the Weibull case is surprising. There it depends onn, whether the record or the i.i. d. observations have more FI. We propose new estimators based on record data. The results may be of interest in some life testing situations. Supported in part by Fondo Nacional de Desarrollo Cientifico y Tecnologico (FONDECYT) grant # 1010222 of Chile.     

核电产品生命周期成本研究

随着核电在我国能源结构中的地位逐渐提高,人们对其经济性的关注度日益增强。传统成本理论下计算的核电成本拘泥于核电企业发生的内部成本,已不能满足社会对于全面了解核电成本的需求。文章运用产品生命周期成本理论对核电成本进行细致剖析,总结出其除传统成本外,还包括环境成本、健康成本及安全成本,这三大成本贯穿于核电形成始终。文章并对其构成进行了分析且对其核算与报告的方法展开了初步探究。     

On some stepdown procedures with application to consistent variable selection in linear regression

The paper considers the problem of consistent variable selection with the use of stepdown procedures in the classical linear regression model and for the model with dependent errors. The stated results complete the results obtained by Bunea et al. [Consistent variable selection in high dimensional regression via multiple testing. J Stat Plann Inference. 2006;136(12):4349–4364].