BIAS IN LIST-ASSISTED TELEPHONE SAMPLES

A number of researchers have suggested list-assisted samplingfor the selection of telephone households to overcome some ofthe operational difficulties associated with the Mitofsky-Waksbergmethods of random digit dialing (RDD). An advantage of a list-assistedmethod of RDD is that an equal probability systematic sampleof telephone numbers can be selected and the variances of estimatesfrom such a sample are usually lower than from a clustered designlike the Mitofsky-Waksberg method. The main disadvantage ofthe list-assisted method is that it excludes some householdsfrom the sample, thus creating a coverage bias in the estimates.This article describes research on the coverage bias for a particularmethod of list-assisted sampling. The two key determinants ofcoverage bias are the proportion of households that are noteligible for the sample and the differences in the characteristicsof the covered and not covered populations. The results showthat about 4 percent of all households are excluded in nationalsamples using this method of sampling. Furthermore, they showthat the differences between the covered and uncovered populationsare generally not large. The coverage bias resulting from theseconditions may often be small.     

The arithmetic of growth: Methods of calculation

This is a tutorial on the relations between population data and the rates of growth that are calculated from the data. For the calculation of rates of growth, discrete and continuous compounding will be compared so that the reader can see the reasons for using the mathematics of continuous compounding, which is the mathematics of exponential growth. Some properties of exponential growth are developed. Semi-logarithmic graphs will be discussed as a device for representing the size of growing populations and for analyzing the nature of the growth. Illustrative examples will be worked out in order to emphasize applications and utility.     

Multiparameter evidence synthesis in epidemiology and medical decision-making: current approaches

Summary.  Alongside the development of meta-analysis as a tool for summarizing research literature, there is renewed interest in broader forms of quantitative synthesis that are aimed at combining evidence from different study designs or evidence on multiple parameters. These have been proposed under various headings: the confidence profile method, cross-design synthesis, hierarchical models and generalized evidence synthesis. Models that are used in health technology assessment are also referred to as representing a synthesis of evidence in a mathematical structure. Here we review alternative approaches to statistical evidence synthesis, and their implications for epidemiology and medical decision-making. The methods include hierarchical models, models informed by evidence on different functions of several parameters and models incorporating both of these features. The need to check for consistency of evidence when using these powerful methods is emphasized. We develop a rationale for evidence synthesis that is based on Bayesian decision modelling and expected value of information theory, which stresses not only the need for a lack of bias in estimates of treatment effects but also a lack of bias in assessments of uncertainty. The increasing reliance of governmental bodies like the UK National Institute for Clinical Excellence on complex evidence synthesis in decision modelling is discussed.     

英汉思维方式对语言结构的影响

思维方式对语言的结构有哪些影响?本文从形合与意合在句法上与章法上的不同表现,论述了英汉两种语言在结构和表达方式上的不同,并通过实例归纳出一些具体做法,供同行进一步探讨。     

Corporate Governance and Director Accountability: an Institutional Comparative Perspective*

This paper examines the role of boards of directors in light of institutional contingencies and recent best practice governance guidelines and regulation such as the United Kingdom Higgs Review and the United States Sarbanes‐Oxley Act 2002. Particular attention is paid to discussing the role of independent directors across countries, and the implications for corporate governance innovation. It concludes by posing questions about recent corporate governance transformations and providing suggestions for future research.     

The 'negotiated night': an embodied conceptual framework for the sociological study of sleep

Sleep is essential for our health and well‐being but it has, historically, been the subject of little sociological study. Yet sleep is not, as common sense would have us believe, ‘asocial inaction’. Like our waking lives, it is a time of interaction. The sociology of sleep presently exists in a state similar to the early stages of development of the sociology of the body, waiting for something like Frank's (1991 ) typology of body action, which served as a heuristic guide through which action and its multifaceted components could be understood. This paper argues that one productive analytical framework is to adapt Watson's (2000 ) ‘male body schema’ for the sociological investigation of sleep. This revolves around four interrelated forms of embodiment: normative (opinions and perceptions about healthy sleep behaviour); pragmatic (‘normal’ as related to social role); experiential (feelings related to sleep); and visceral (the biological body and sleep). The possibilities this model provides for the sociology of sleep is illustrated in the paper through the analysis of a case study of sleep negotiation between a couple.