Improvements over the duplicate performance method for outlier detection in categorical multivariate surveys

Summary The detection of errors and outliers is an important step in data processing, especially those errors arising from data entry operations because they are of the entire responsability of the data processing staff. The duplicate performance method, is commonly used as an attempt to detect such type of errors. It implies typically typing twice the same data without any special precedence. If the errors are uniformly distributed among individuals, retyping a fraction of the total will also remove typically the same fraction of the errors. A new method is presented, which is able to improve that procedure by sorting the records putting first the most unlikely ones. The ability of the present methodology has been tested by a Monte Carlo simulation, using an existing database of categorical answers of housing characteristics in Uruguay. At first, it has been randomly contaiminated, and after that, the proposed procedure applied. The results show that if a partial retyping is done following the proposed order about 50 % of the errors can be removed while keeping the retyping effort between 4 and 14% of the dataset, while to attain a similar result with the standard methodology 50% (on, average) of the database should be processed. The new ordering is based upon the unrotated Principal Component Analysis (PCA) transformation of the previously coded data. No special shape of the multivariate distribution function is assumed or required.     

Tract- and county-level income inequality and individual risk of obesity in the United States

ObjectivesWe tested three alternative hypotheses regarding the relationship between income inequality and individual risk of obesity at two geographical scales: U.S. Census tract and county.MethodsIncome inequality was measured by Gini coefficients, created from the 2000 U.S. Census. Obesity was clinically measured in the 2003–2008 National Health and Nutrition Examination Survey (NHANES). The individual measures and area measures were geo-linked to estimate three sets of multi-level models: tract only, county only, and tract and county simultaneously. Gender was tested as a moderator.ResultsAt both the tract and county levels, higher income inequality was associated with lower individual risk of obesity. The size of the coefficient was larger for county-level Gini than for tract-level Gini; and controlling income inequality at one level did not reduce the impact of income inequality at the other level. Gender was not a significant moderator for the obesity-income inequality association.ConclusionsHigher tract and county income inequality was associated with lower individual risk of obesity, indicating that at least at the tract and county levels and in the context of cross-sectional data, the public health goal of reducing the rate of obesity is in line with anti-poverty policies of addressing poverty through mixed-income development where neighborhood income inequality is likely higher than homogeneous neighborhoods.     

Census data issues for epidemiology and health risk assessment: experiences from the Small Area Health Statistics Unit

Summary.  Census data are vital components of epidemiological studies, but the issues that are involved in using these data in such studies are often not fully appreciated. The paper describes some of the problems and uncertainties that arise, and some of the approaches that can be used to address them, based on experience in the Small Area Health Statistics Unit at Imperial College London. Issues considered include the geography of census data (zone design systems, recasting and the role of postcodes), temporal aspects of census data (especially in relation to migration and population change) and information content (especially in relation to characterization of socio-economic status). In the light of these issues, opportunities to improve the resolution and utility of census data for epidemiological studies are discussed.     

Using the 2001 census to study human capital movements affecting Britain's larger cities: insights and issues

Summary.  Human capital is increasingly being recognized as crucial to the sustained growth of British cities, and the population census is unrivalled as a source of data on the characteristics of people moving to and from cities. Taking advantage of new features in the 2001 census, the paper examines how successful 27 of Britain's largest cities and their regions are in maintaining their labour force complement, giving particular attention to young adults and people working in high level occupations. Considerable variation is apparent between city regions, but the interpretation of results is somewhat hampered by limitations in the census data, prompting recommendations for future data collection.     

Reply

Beginning with the 1990 Census and the January 1992 Current Population Survey (CPS), the Bureau of the Census changed the emphasis of its educational-attainment question from years of education to degree receipt. Using a matched sample from the 1991 and 1992 March CPS, this article addresses how to reconcile the old and new questions. The effects of those methods on the estimated return(s) to education are then examined. Both the estimated linear return and the estimated college–high-school wage differential are slightly larger using information from the new question.     

国外人口普查：从全面调查到行政记录

人口普查的传统方法是全面调查。这种方法的缺陷是成本高、居民负担重和数据质量不高。为了改变这个局面．一些国家正在尝试或者是已经把行政记录作为人口普查数据来源。     

人口普查净误差构成部分的估计

 人口普查误差,即普查登记人数与“人口数真值”之差,也叫净误差,实际上是普查遗漏人数抵消普查错误计数人数的结果。净误差掩盖了人口普查中所发生的错误计数和遗漏这两个方面的错误的真实情况。美国普查局决定,在2010年人口普查的事后质量检查中,除了像以往一样继续估计净误差之外,还将估计错误计数人数和遗漏人数。这是对人口普查事后质量检查工作的一项重大改进。本文在解读有关文献的基础上,讨论了估计错误计数人数和遗漏人数的途径、数据准备以及抽样估计的有关问题。     

普查涵盖误差及其测量机制研究

 针对周期性普查的统计数据质量,本文在界定普查涵盖误差的基础上,从分析普查涵盖误差与抽样框误差的异同入手,以此为基础讨论普查涵盖误差的构成及分类,将普查涵盖误差特点概括为全面性、过程性和偏差性;将普查涵盖误差测量思路与重复调查技术假定相结合,论述基于抽样设计和基于双系统模型的测量机制,用于分析事后抽查对不同普查涵盖误差的测量技术假定,为进行我国普查事后抽查的后续研究奠定理论基础。     

流动的人权：和谐社会语境下的流动人口的人权保障

改革开放以来,法律为市场经济的发展与流动人口的管理提供了制度基础。然而作为法治核心内容之一的人权．特别是对经济发展和城市建设作出重要贡献的流动人口的人权并没有能够得到切实的保障。基于建设和谐社会这一背景。笔者认为流动人口的人权现状是影响社会和谐的重要因素,流动人口的人权保障应该成为和谐社会建设的重要内容。由此,法律不应该仅仅是管理流动人口,而更应该在保障流动人口的人权方面发挥重要作用。     

美国2010年人口普查方法介绍

 本文根据美国人口普查局网站资料,介绍了美国2010年人口普查的调查目的、内容、具体组织实施方法等,其科学的调查设计方法、规范的操作流程、先进的数据收集和处理方法及丰富的公开信息资源,为我国2010年人口普查提供了参考,有利于加快完善我国人口普查制度,实现及时准确反映全国及各地的人口变化情况。