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.     

论新闻报道策划的实践意义

新闻报道策划 在近几年的新闻实践中应用非常广泛。就报道主题、整合信息、沟通受众和发挥媒体整体优 势等方面论述了新闻报道策划的实践意义。     

苗族现代化的希望--四川苗族地区小场镇建设问题思考

关于四川苗区现代化问题 ,本文从近代苗族山区开发状凸现苗族住山的经验 ,从当代苗族在山面临的挑战及二十年来改革开放实践所探索出的初俱模式与方向 ,求证苗族地区现代化的最大特点“山”因素 ,旨在提高苗族地区现代化建设的理论认识和层面 ,进而再证少数民族地区改革开放与现代化建设具有其自身的特点和规律。     

电子档案管理探微

电子档案是信息技术不断发展的产物,将逐步成为档案管理的主要对象。在分析我国电子档案管理现状的基础上,文章着重探讨了保证电子档案的凭证性的技术措施和管理措施,同时讨论了如何科学、有效地提供电子档案利用。     

浅析新时期我国人口较少民族的扶贫开发对策

改革开放以来,我国人口较少民族在各方面得到了巨大的发展,然而,由于粗放式发展、自然环境、历史等方面的原因,我国人口较少民族少数地区仍至今存在着不同程度的贫困问题,影响了小康社会的全面实现。本文即围绕我国人口较少民族的部分特殊性,以科学发展观为指导,探讨在新的历史时期我国人口较少民族的扶贫开发对策。     

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.     

阿以民族冲突的现状及解决前景

夹杂着错综复杂民族和宗教矛盾以及大国背景的阿以冲突,已成为当今国际社会最为关注的热点问题.审视阿以冲突的现状,展望中东和平的未来,展现在世人面前的是一幅两个民族的苦难历史,留在人类心灵深处的则是和平与发展的历史思考.     

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。