Estimating household structure in ancient China by using historical data: a latent class analysis of partially missing patterns

Summary.  Social data often contain missing information. The problem is inevitably severe when analysing historical data. Conventionally, researchers analyse complete records only. Listwise deletion not only reduces the effective sample size but also may result in biased estimation, depending on the missingness mechanism. We analyse household types by using population registers from ancient China (618–907 AD) by comparing a simple classification, a latent class model of the complete data and a latent class model of the complete and partially missing data assuming four types of ignorable and non-ignorable missingness mechanisms. The findings show that either a frequency classification or a latent class analysis using the complete records only yielded biased estimates and incorrect conclusions in the presence of partially missing data of a non-ignorable mechanism. Although simply assuming ignorable or non-ignorable missing data produced consistently similarly higher estimates of the proportion of complex households, a specification of the relationship between the latent variable and the degree of missingness by a row effect uniform association model helped to capture the missingness mechanism better and improved the model fit.     

一种求解双目标线性规划的方法及其在上海市土地使用和交通方面的应用

本文介绍了一种求解双目标线性规划(SBLP)的方法.根据上海市土地使用与交通的现状建立了一个拟动态的模型(BOLT),并用该方法加以求解。根据得到的解对上海市土地使用与交通相互作用的情况进行了分析。     

经济全球化影响下的中国计划生育发展趋势

中国的计划生育是在计划经济体制下形成的,其特点多数与经济全球化的规则有着较大的差距。因此,经济全球化和中国加入世贸组织对中国计划生育的影响是全面而深刻的。在经济全球化的影响下,中国计划生育的发展趋势主要体现在六个方面。     

An individual measure of relative survival

Summary.  Relative survival techniques are used to compare survival experience in a study cohort with that expected if background population rates apply. The techniques are especially useful when cause-specific death information is not accurate or not available as they provide a measure of excess mortality in a group of patients with a certain disease. Whereas these methods are based on group comparisons, we present here a transformation approach which instead gives for each individual an outcome measure relative to the appropriate background population. The new outcome measure is easily interpreted and can be analysed by using standard survival analysis techniques. It provides additional information on relative survival and gives new options in regression analysis. For example, one can estimate the proportion of patients who survived longer than a given percentile of the respective general population or compare survival experience of individuals while accounting for the population differences. The regression models for the new outcome measure are different from existing models, thus providing new possibilities in analysing relative survival data. One distinctive feature of our approach is that we adjust for expected survival before modelling. The paper is motivated by a study into the survival of patients after acute myocardial infarction.     

Identifying race and ethnicity in the 1979 National Longitudinal Survey of Youth

The 1979 National Longitudinal Survey of Youth is among the few surveys to provide multiple reports on respondents’ race and ethnicity. Respondents were initially classified as Hispanic, black, or “other” on the basis of data collected during 1978 screener interviews. Respondents subsequently self-reported their “origin or descent” in 1979, and their race and Hispanic origin in 2002; the latter questions conform to the federal standards adopted in 1997 and used in the 2000 census. We use these data to (a) assess the size and nature of the multiracial population, (b) measure the degree of consistency among these alternative race-related variables, and (c) devise a number of alternative race/ethnicity taxonomies and determine which does the best job of explaining variation in log-wages. A key finding is that the explanatory power of race and ethnicity variables improves considerably when we cross-classify respondents by race and Hispanic origin. Little information is lost when multiracial respondents are assigned to one of their reported race categories because they make up only 1.3% of the sample.

知识经济与人口发展

知识经济将是经济发展的主流 ,它要求社会对科技有巨大的投入 ,而这种投入对经济和社会有更大的回馈 ;知识产业将成为经济结构中的主导产业 ;知识经济以知识价值为核心 ;在知识经济时代世界经济将形成全球化的新格局 ,并对传统产业进行技术改造。知识经济时代对人口数量的制约因素将主要是环境的和空间的适度 ;对提高人口素质的要求更为迫切 ;人口的经济结构将发生重要变化 ,知识工人将成为社会的主导力量 ;人口分布与迁移也将出现集中化分散化的新特点。知识经济对人口学研究提出了更高要求 ,人口学研究手段要实现现代化和信息化 ;人口学要开放化     

立足服务 改革基层人口计划管理机制

基层人口计划是各级人口计划的基础 ,也是落实人口计划时的执行计划 ,它直接影响到家家户户。现行基层人口计划的管理措施中 ,有些地方亟待完善。改革现行基层人口计划管理机制 ,让群众自愿选择生育时间已成为计划生育工作发展的必然要求     

城市迁移人口及管理问题探讨

改革开放以来中国城市人口增长的最主要来源是人口的迁移增长 ,因此城市人口管理体制的重要一环是城市人口迁移的管理。本文根据城市人口迁移管理体制及其相关的问题进行分析 ,提出了要科学地依据自然资源与社会资源测定城市的人口承载力 ,对人口迁移增长的控制有科学的根据 ,对人口迁移增长有目标、有规划 ,并对城市人口迁移进行科学管理的创见     

21世纪我国老年人口规模与老年人力资源开发

21世纪上半叶将是老年人口数量及老龄化突进的时期。老年人力资源是人力资源构成的重要组成部分 ,建立市场机制 ,把老年人愿为现代化建设作贡献的主观愿望和能力 ,与社会发展对老年人力资源的客观需要 ,合理、有效地结合 ,促进人口经济协调发展     

澳门人口发展史的启迪

本文对澳门人口发展演进的过程和影响因素进行了分析 ,并提出了澳门回归后人口发展的对策