Distribution and Expected Time of Residence for U.S. Households

For risk assessments, the average current residence time (time since moving into current residence) has often been used as a surrogate for the average total residence time (time between moving into and out of a residence). Since the distributions of the two quantities are not necessarily the same, neither are their averages. Housing surveys provide current residence time data; total residence times must, therefore, be inferred. By modeling the moving process, the total residence time distribution can be estimated from current residence time data. Using 1985 and 1987 U.S. housing survey data, distributions and averages for both current and total residence times were calculated for several housing categories. The average total residence time calculated for all U.S. households, 4.6 ( se = 0.6) years, is less than half the average current residence time, 10.6 ( se = 0.1) years.     

由广东和上海看城市化对人口控制的关键作用

1993年上海首次出现人口负增长以来,人口生育率连续保持负数,其人口绝对数增长主要缘于人口的机械增长。同时,北京、天津、沈阳等城市也陆续出现了人口生育率的急剧下降。而与此相对应的,是广东虽然自改革开放以来一直是经济发展的领先省份,深得市场经济风气之先,其人口控制却是老大难省份。通过两者对比,笔者认为,市场经济只有与城市化、现代化相结合,才能起到人口控制的作用。     

对我校本科生考研意向的调查与分析

随着就业形势的日趋严峻,越来越多的本科生选择了考研来谋求个人的发展.文章采用调查问卷的方式,对地方工科院校本科生的考研意向进行了详细的了解,并在此基础上进行了多项目的详尽分析.     

小型经济单位从业人员调查抽样方法研究

不执行统计报表制度的小型经济单位的从业人员统计,应当用抽样调查方法进行。小型经济单位的各种统计调查项目,其中如生产统计调查项目、经营统计调查项目、劳动统计调查项目等等,应当合并在一起并分行业进行抽样调查。对小型工业单位进行从业人员调查的抽样技术,包括:样本轮换方针、在样本轮换条件下如何构造估计量、怎样对估计量的方差进行估计等。     

An alternative view of the 2001 census and future census taking

Summary.  The 2001 census in the UK asked for a return of people 'usually living at this address'. But this phrase is fuzzy and may have led to undercount. In addition, analysis of the sex ratios in the 2001 census of England and Wales points to a sex bias in the adjustments for net undercount—too few males in relation to females. The Office for National Statistics's abandonment of the method of demographic analysis for the population of working ages has allowed these biases to creep in. The paper presents a demographic account to check on the plausibility of census results. The need to revise preliminary estimates of the national population over a period of years following census day—as experienced in North America and now in the UK—calls into question the feasibility of a one-number census. Looking to the future, the environment for taking a reliable census by conventional methods is deteriorating. The UK Government's proposals for a population register open up the possibility of a Nordic-style administrative record census in the longer term.     

Exact filtering for partially observed continuous time models

Summary.  The forward–backward algorithm is an exact filtering algorithm which can efficiently calculate likelihoods, and which can be used to simulate from posterior distributions. Using a simple result which relates gamma random variables with different rates, we show how the forward–backward algorithm can be used to calculate the distribution of a sum of gamma random variables, and to simulate from their joint distribution given their sum. One application is to calculating the density of the time of a specific event in a Markov process, as this time is the sum of exponentially distributed interevent times. This enables us to apply the forward–backward algorithm to a range of new problems. We demonstrate our method on three problems: calculating likelihoods and simulating allele frequencies under a non-neutral population genetic model, analysing a stochastic epidemic model and simulating speciation times in phylogenetics.     

Regression analysis and ratio analysis for domains: A randomization-theory approach

In most surveys, inference for domains poses a difficult problem because of data shortage. This paper presents a probability sampling theory approach to some common types of statistical analysis for domains of a surveyed population. Simple and multiple regression analysis, and analysis of ratios are considered. Two new methods are constructed and explored which can improve substantially over the common method based on sample-weighted sums of squares and products. These new methods use auxiliary variables whose importance depends on the extent to which they succeed in explaining certain patterns in the regression residuals. The theoretical conclusions are supported by empirical results from Monte Carlo experiments.     

Estimating Marihuana Usage Using Randomized Response—Some Paradoxical Findings

A randomized response technique was used in parallel with direct questioning on the (illegal) usage of marihuana in a population survey of Canberra. Estimates of usage from the randomized questions were much lower than those obtained directly. A number of possible explanations for these paradoxical findings are considered.     

ESTIMATING POPULATION SIZE FROM CAPTURE-RECAPTURE EXPERIMENTS IN CONTINUOUS TIME

Estimates for the size of a closed population are given for multiple recapture studies in continuous time. The estimates are derived by a method of moments for martingales. An estimate and associated standard error of the population size are derived for a homogeneous population when the capture rates are permitted to depend on time in an unspecified manner. Corresponding results are obtained when the capture rates vary among individuals as well. Explicit expressions are given for these estimates and standard errors which involve only simple computation.     

流人遣戍与清代东北儒学的演变

儒学在古代东北地区的传播,是"用夏变夷"与"忻慕汉化"合力的结果.但在清前期,源于少数民族建立大一统王朝的性质,东北儒学有着自身独特的发展历程.在清初"旗民两属二重管理体制"与封禁政策所构成的基本框架与空间内,为了维护本民族特质,官办儒学发展滞后,为文化流人儒学教育活动所补充,特别是在吉林、黑龙江地区,儒学的传播主要是由文化流人推动的.文化流人传播儒学的活动,最初与维护"国语骑射"等满洲习俗并不相悖;但随着儒学的传播,八旗子弟学习儒学热情的高涨,有碍满洲风俗,导致东北儒学政策有异于汉地儒学,由此可见统治者维护本民族特质的目的.