The case for small area microdata

Summary.  Census data are available in aggregate form for local areas and, through the samples of anonymized records (SARs), as samples of microdata for households and individuals. In 1991 there were two SAR files: a household file and an individual file. These have a high degree of detail on the census variables but little geographical detail, a situation that will be exacerbated for the 2001 SAR owing to the loss of district level geography on the individual SAR. The paper puts forward the case for an additional sample of microdata, also drawn from the census, that has much greater geographical detail. Small area microdata (SAM) are individual level records with local area identifiers and, to maintain confidentiality, reduced detail on the census variables. Population data from seven local authorities, including rural and urban areas, are used to define prototype samples of SAM. The rationale for SAM is given, with examples that demonstrate the role of local area information in the analysis of census data. Since there is a trade-off between the extent of local detail and the extent of detail on variables that can be made available, the confidentiality risk of SAM is assessed empirically. An indicative specification of the SAM is given, having taken into account the results of the confidentiality analysis.     

Exploring the economic and social determinants of psychological well-being and perceived social support in England

Summary.  A fundamental focus of Government concern is to enhance well-being. Recently, policy makers in the UK and elsewhere have recognized the importance of the community and society to the well-being of the nation as a whole. We explore the extent to which economic and social factors influence the psychological well-being of individuals and their perceptions of the social support that they receive, using Health Survey for England data. We employ a random-effects ordered probit modelling approach and find that unobserved intrahousehold characteristics help to explain the variation in our dependent variables, particularly for co-resident females. Our results indicate that individuals with acute and chronic physical illness, who are female, unemployed or inactive in the labour market and who live in poor households or areas of multiple deprivation report lower levels of psychological well-being. Reduced perceptions of social support are associated with being male, single or post marriage, from an ethnic minority, having low educational attainment and living in a poor household, but are not statistically related to area deprivation measures. These findings may help to inform the contemporary policy debate surrounding the promotion of individual well-being and community, through the alleviation of social exclusion.     

我国赤潮的成因和防治

赤潮频发作为海洋的生态灾难，正在成为我国沿海经济可持续发展的一个制约因素，本文探讨了我国赤潮的形成原因、危害和防治措施．     

再论发挥持“绿卡”留学人员的作用

在知识经济到来的今天 ,一切的竞争归根到底就是人才的竞争 ,持“绿卡”留学人员是国家特殊的宝贵财富和重要人才资源 ,我们有必要站在“国际人才争夺战”的高度和“人才资源观”的角度对他们进行再认识 ,抓住改革的机遇 ,总结经验 ,切实做好持“绿卡”留学人才资源的挖掘和开发工作 ,迎接新的挑战     

我国农村生物质能源利用研究——沼气发酵与生物质直接燃烧的技术经济效果对比分析

在我国农村，农作物秸杆等副产品主要作为炊事燃料而直接烧掉。文章将秸杆等进行沼气发酵和直接燃烧的技术经济效果，从能量转移、物质循环和生态平衡三个方面进行对比分析，并指出，沼气发酵才是生物质利用最合理、最经济的途径。     

视觉文化与当代读者审美趣味的转向

通过对当代都市面貌、电影、电视等的研究,探讨了视觉文化语境中当代文化接受者的审美趣味和接受习惯所发生的巨大转变。指出视觉文化中的文化接受对象主要是以观众的形式存在的,可见,当代小说的潜在读者实际上存在于这些视觉观众之中,因而小说如若试图继续保持其一定的影响力,则必须从视觉观众的群体中争取自己的读者。同时,观众们日益习惯于追求戏剧化、震惊、奇观化效果以及对自身窥视欲的满足。     

工程流体力学课程采用英语原版教材效果调查

部分专业基础课采用英语原版教材是上海理工大学动力工程学院已实行多年的重要教改措施.为了较确切地了解这种教学方式的实际效果,作者对学生进行了一次问卷调查.本文详细介绍了调查的结果,对存在问题作出分析并提出了改进建议.     

Generalized linear mixed models for ordered responses in complex multilevel structures: effects beneath the school or college in education

Summary.  The complexities of educational processes and structure and the need for disentangling effects beneath the level of the school or college are discussed. Ordinal response multilevel crossed random-effects models for educational grades are introduced. Weighted random effects for teacher contributions are then added. Estimation methodology is reviewed. Specially written macros for quasi-likelihood with second-order terms are described. The application discusses General Certificate of Education at advanced level grades cross-classified by student and teaching group within a number of institutions. The methods handle teacher effects where several teachers contribute to provision and where each teacher deals with several groups. Some methodological lessons are drawn for sparse data and the use of extra-multinomial variation. Developments of the analysis yield conclusions about the sources of variation in educational progress, and particularly the effect of teachers.     

我国上市公司资本结构调整行为研究

以620家中国上市公司1998-2005年间财务数据为样本,对其资本结构动态调整行为进行实证研究。通过采用固定效应方法对部分调整模型进行估计,验证了该理论对中国股票市场的解释能力。结果表明我国上市公司的确以每年大约40%的速度缩小真实值与目标值之间的差距,调整的方式主要是通过负债的变动。公司其他的特征变量如资产收益率、资产折旧率、公司规模和股权结构等都对动态调整过程有显著的影响。     

Estimating percentile-specific treatment effects in counterfactual models: a case-study of micronutrient supplementation, birth weight and infant mortality

Summary.  Clinical trials of micronutrient supplementation are aimed at reducing the risk of infant mortality by increasing birth weight. Because infant mortality is greatest among the low birth weight (LBW) infants (2500 g or under), an effective intervention increases the birth weight among the smallest babies. The paper defines population and counterfactual parameters for estimating the treatment effects on birth weight and on survival as functions of the percentiles of the birth weight distribution. We use a Bayesian approach with data augmentation to approximate the posterior distributions of the parameters, taking into account uncertainty that is associated with the imputation of the counterfactuals. This approach is particularly suitable for exploring the sensitivity of the results to unverifiable modelling assumptions and other prior beliefs. We estimate that the average causal effect of the treatment on birth weight is 72 g (95% posterior regions 33–110 g) and that this causal effect is largest among the LBW infants. Posterior inferences about average causal effects of the treatment on birth weight are robust to modelling assumptions. However, inferences about causal effects for babies at the tails of the birth weight distribution can be highly sensitive to the unverifiable assumption about the correl-ation between the observed and the counterfactuals birth weights. Among the LBW infants who have a large causal effect of the treatment on birth weight, we estimate that a baby receiving the treatment has 5% less chance of death than if the same baby had received the control. Among the LBW infants, we found weak evidence supporting an additional beneficial effect of the treatment on mortality independent of birth weight.