Changes in the geographical mobility of the population of Poland

Spatial mobility in Poland is analyzed for the period 1976-1989. The focus is on the decline in internal migration over time and its causes. The analysis includes migration between rural and urban areas as well as migration among voivodships. Factors affecting migration include changes in the age distribution; however, the authors conclude that changes in migration patterns are primarily due to socioeconomic factors, particularly the economic crises the country has faced in recent years.     

The concept of spatial order and other problems of regional research in demography

The concept of spatial demographic order is introduced and defined as the preferred spatial distribution of a given demographic variable. The results of a multivariate statistical analysis of demographic trends in rural and urban areas in Poland are presented to illustrate the convergence of such trends in the areas studied. The author concludes that the increasing similarity in demographic processes between rural and urban areas is due mainly to migration.     

城乡居民储蓄行为差异的实证研究

城乡居民储蓄行为差异的实证研究周伏平王美今ＡＢＳＴＲＡＣＴＴｈｉｓｐａｐｅｒｓｈｏｗｓｕｐｔｈｅｄｉｆｅｒｅｎｃｅｏｆｔｏｔａｌｓａｖｉｎｇ（ｏｎｌｙｒｅｆｅｒｉｎｇｔｏｔｈｅｒｅｓｉｄｅｎｔｓ＇ｓａｖｉｎｇｄｅｐｏｓｉｔｓ,ｎｏｔｉｎｃｌｕｄｉｎｇ...     

劳动力转移与粮食安全

中国快速城市化和工业化导致的大量农村劳动力向城市转移引起了决策者和学术界对粮食安全问题的担忧,但本文利用县级和农户面板数据研究发现：首先,即使到2010年,农村劳动力转移对粮食总产量的影响并不大,对主产区的粮食总产量的影响更小,这背后的机制是主产区农户会通过更多地增加其他农业生产要素来替代劳动力投入的减少;其次,劳动力转移对主产区和非主产区农户的粮食生产行为的影响以及对主要粮食作物和次要粮食作物的影响都有所不同。总之,农村劳动力迁移尚未严重威胁到中国的粮食安全,当然,政府应针对粮食主产区和非主产区实施不同的政策以保持粮食总产量的稳定,特别是要鼓励主产区的耕地流转以降低劳动力迁移的负面影响。     

中国农村人口流动的影响因素与实施对策——基于推拉理论的托达罗修正模型

中国农村剩余劳动力数量巨大,如何在城市就业空间有限的情况下有效地解决中国农村剩余劳动力的合理转移问题,是推进城镇化和提升农民收入以及实现社会稳定和可持续发展的重要举措之一。在托达罗人口流动模型的基础上,引入"推拉理论",结合中国农村人口流动实际状况,对托达罗人口流动模型进行修正,并以此构建多元回归模式进行逐步回归分析,结果表明:在农村人口流动的过程中应当加快第二、第三产业的发展,加大培训"农民工"专业技能的力度;深化体制改革,消除城乡二元分割的制度壁垒,构建城乡衔接的社会福利制度;加快工业化和城市化进程,建立城乡统一的劳动力市场,从而进一步促进农村劳动力人口向城镇的有效转移。     

Statistical materials. Results of the 1985 socio-demographic sample survey of the population

Results from the five percent socio-demographic sample survey of the USSR conducted in 1985 are presented. Data are provided on the educational status of the population and the labor force by nationality, republic, sex, and rural or urban area; income; marital status; marriage duration; divorce and separation; intervals between marriages; family size; family characteristics; families with children under 18; internal migration; and distribution of women by number of children ever born, republic, nationality, educational status, and expected family size     

中国代际收入传递趋势及教育在传递中的作用

本文利用中国健康营养调查（CHNS）数据,实证检验了出生于1949-1990年男性是否存在代际收入传递,并分析了其变化趋势和教育在代际收入传递中的作用机制。估计结果表明,1949- 1990年代际收入传递程度总体上不断加强,其中60年代初期和80年代初期出现两次传递高峰。中等收入水平者受父辈的影响及加强趋势均最高,呈现双倒“U”特征。城镇传递加强趋势约是农村2倍,城镇高收入水平者受父辈的影响更强,农村则低收入水平者所受影响更强。对教育作用机制分解发现,教育对代际收入传递的解释程度在农村达到26%,城镇则达到36%。家庭环境导致的子女教育机会不平等是影响代际收入传递趋势变化的最主要原因。随着国民教育水平提高,在中国教育的作用也出现了”组合效应”特征。     

中国城乡居民代际收入流动分析

利用CGSS提供的中国28个省区微观调查数据,应用Atkinson回归模型和转移矩阵两种度量代际收入流动性的方法,研究了中国2005年的城乡居民代际收入流动性及其影响因素。研究发现：代际收入在不同的分类下流动弹性并不大,其中城市的流动高于农村;东、中、西部的流动弹性呈现逐渐递减趋势。利用转移矩阵对流动性进行测度,研究表明：总体的代际收入流动有一种保持效应,即从最低等级转向高一等级的概率较小,从最高等级转向低一等级的概率也较小,总体的不同等级间的流动性较差。性别、年龄、受教育年限和家庭背景对个人收入的高低起着积极的作用。     

与收入相关的健康不平等扩大了吗

引致健康不平等原因在很大程度上可追溯到收入不平等。本文利用中国营养与健康调查数据,采用建立在追踪调查样本上的集中系数,对1990-2006年间与收入相关健康不平等进行了测度和分解。结果显示：（1）城市和农村都存在着亲富人的健康不平等且累积效应不断深化,初始收入不平等是健康不平等加剧的重要原因;（2）居民平均健康水平有所降低,穷人的健康变动度大于富人,农村的健康不平等大于城市;（3）农村收入不平等扩大带来了健康不平等上升,而城市相关医疗卫生服务水平的提高,使收入不平等扩大对健康不平等的负效应有所减弱。因此,提升公共服务均等化水平、缩小城乡健康差距,是缓解健康不平等的有效途径。     

养老保险可携带性、农村劳动力流动与农村反贫困

本文在三部门经济框架下拓展了Harris和Todaro(1970)关于劳动力流动及其经济与社会影响的H-T模型,对养老保险可携带性影响农村劳动力流动的收入增长效应和贫富调节机制开展了理论及实证研究。结果显示:经济发展水平和产业层级在地区之间的梯度分化与城乡之间高达1.9~2.6倍的收入差距,是农村劳动力向城镇流动以及在不同城镇之间跨区流动的根本原因。养老保险可携带性是通过改变流动成本和流动收益影响农村劳动力的流动效率和流动方向,具有显著的收入增长效应和贫富调节作用。提高养老保险可携带性在2000—2019年间可使农村劳动力收入提高 35%以上,并可使城乡劳动 力收入差距减少15%~34%。有力地验证了《城镇企业职工基本养老保险关系转移接续暂行办法》在城乡协同发展、增加农民收入和缩小城乡贫富差距中的积极作用及其进一步完善的必要性和方向。     

Sparse Markov Chains for Sequence Data

Finite memory sources and variable‐length Markov chains have recently gained popularity in data compression and mining, in particular, for applications in bioinformatics and language modelling. Here, we consider denser data compression and prediction with a family of sparse Bayesian predictive models for Markov chains in finite state spaces. Our approach lumps transition probabilities into classes composed of invariant probabilities, such that the resulting models need not have a hierarchical structure as in context tree‐based approaches. This can lead to a substantially higher rate of data compression, and such non‐hierarchical sparse models can be motivated for instance by data dependence structures existing in the bioinformatics context. We describe a Bayesian inference algorithm for learning sparse Markov models through clustering of transition probabilities. Experiments with DNA sequence and protein data show that our approach is competitive in both prediction and classification when compared with several alternative methods on the basis of variable memory length.     

A Bayesian compartmental model for the evaluation of 1,3-butadiene metabolism

Summary. We propose a Bayesian model for physiologically based pharmacokinetics of 1,3-butadiene (BD). BD is classified as a suspected human carcinogen and exposure to it is common, especially through cigarette smoke as well as in urban settings. The main aim of the methodology and analysis that are presented here is to quantify variability in the rates of BD metabolism by human subjects. A three-compartmental model is described, together with informative prior distributions for the population parameters, all of which represent real physiological variables. The model is described in detail along with the meanings and interpretations of the associated parameters. A four-compartment model is also given for comparison. Markov chain Monte Carlo methods are described for fitting the model proposed. The model is fitted to toxicokinetic data obtained from 133 healthy subjects (males and females) from the four major racial groups in the USA, with ages ranging from 19 to 62 years. Subjects were exposed to 2 parts per million of BD for 20 min through a face mask by using a computer-controlled exposure and respiratory monitoring system. Stratification by ethnic group results in major changes in the physiological parameters. Sex and age were also tested but not found to have a significant effect.     

Estimation with right‐censored observations under a semi‐Markov model

The semi‐Markov process often provides a better framework than the classical Markov process for the analysis of events with multiple states. The purpose of this paper is twofold. First, we show that in the presence of right censoring, when the right end‐point of the support of the censoring time is strictly less than the right end‐point of the support of the semi‐Markov kernel, the transition probability of the semi‐Markov process is nonidentifiable, and the estimators proposed in the literature are inconsistent in general. We derive the set of all attainable values for the transition probability based on the censored data, and we propose a nonparametric inference procedure for the transition probability using this set. Second, the conventional approach to constructing confidence bands is not applicable for the semi‐Markov kernel and the sojourn time distribution. We propose new perturbation resampling methods to construct these confidence bands. Different weights and transformations are explored in the construction. We use simulation to examine our proposals and illustrate them with hospitalization data from a recent cancer survivor study. The Canadian Journal of Statistics 41: 237–256; 2013 © 2013 Statistical Society of Canada     

20年来张家界旅游发展的民生福利考察

依据“从旅游中进去,从民生中出来”的研究思路,在构建概念模型基础上,运用1989-2009年张家界统计数据,利用居民收入增长弹性系数、森指数、基尼系数、居民收入比指数、消费差距比指数和旅游服务密度指数6个指标,对张家界民生福利改善过程的整体情况和城乡差别进行分析,结果发现：（1）张家界城乡居民从旅游业发展中所获得的收入增长基本同步,居民收入增长慢于旅游产业的增长;同时,在城乡居民之间也存在差距,城镇居民收入增长弹性比农村高0．05;（2）张家界旅游开发带动民生福利改善,在城市和农村之间是不平衡的,农村居民福利改善的速度既落后于城镇居民,也落后于财政收入增长;（3）随着旅游服务密度的提高,城乡收入差距比和消费差距大体经历了一个先升后降的过程。     

Bivariate Semi-Markov Process for Counterparty Credit Risk

We consider the problem of constructing an appropriate multivariate model to study counterparty credit risk in the credit rating migration problem. For this financial problem different multivariate Markov chain models were proposed. However, the Markovian assumption may be inappropriate for the study of the dynamics of credit ratings, which typically show non Markovian-like behavior. In this article, we develop a semi-Markov approach to study the counterparty credit risk by defining a new multivariate semi-Markov chain model. Methods are given for computing the transition probabilities, reliability functions and the price of a risky Credit Default Swap.     

Likelihood Ratio Testing for Hidden Markov Models Under Non-standard Conditions

Abstract.  In practical applications, when testing parametric restrictions for hidden Markov models (HMMs), one frequently encounters non-standard situations such as testing for zero entries in the transition matrix, one-sided tests for the parameters of the transition matrix or for the components of the stationary distribution of the underlying Markov chain, or testing boundary restrictions on the parameters of the state-dependent distributions. In this paper, we briefly discuss how the relevant asymptotic distribution theory for the likelihood ratio test (LRT) when the true parameter is on the boundary extends from the independent and identically distributed situation to HMMs. Then we concentrate on discussing a number of relevant examples. The finite-sample performance of the LRT in such situations is investigated in a simulation study. An application to series of epileptic seizure counts concludes the paper.     

工作条件、工资补偿与劳动力市场城乡分割测量

鉴于工资既是对劳动者生产率贡献的支付同时又是对劳动者承受负面工作条件的补偿这一复杂性,鉴于城镇劳动力市场上城乡两类劳动者在艰苦危险程度不等岗位上分布的显著差异性,依据调查工资的城乡差异来测量劳动力市场上城乡分割的程度可能不尽客观。本文关注岗位的工作条件及其工资补偿,依据两类劳动者的可比工资差异观察城乡分割状态。研究发现：在绝对意义上,无论城镇工还是农民工,艰苦危险的工作条件未能带来显著更高的工资正效应;但相对于城镇工,农民工的工资中包含了更多的基于艰苦危险工作条件的岗位补偿部分;在岗位补偿可比口径下,城乡劳动者的工资差异显著大于调查工资口径下的工资差异。以此判断,我国城镇劳动力市场存在以负面工作条件补偿不足为形式的隐性分割,次级劳动力市场中,尤其是哪些最为艰苦和危险的工作岗位上,城乡劳动者看似基本一致的工资水平并不代表农民工获得了平等的生产率回报。     

城镇化进程中人口流动的主观福利效应考察

《2019 年新型城镇化建设重点任务》提出“加快实施以促进人的城镇化为核心、提高质量为导向的新型城镇化战略”。人口流动已然成为城镇化进程中的一个典型社会现象,由此衍生的流动人口与本地居民的福利问题引起广泛关注。本文基于党的十九大提出的“获得感、幸福感、安全感”设计主观福利测度指标,采用中国综合社会调查(CGSS)2015 年调查数据和相匹配的省级数据,通过倾向得分匹配、工具变量回归等方法考察城镇化进程中人口流动所带来的对流动个体自身和城镇本地居民的主观福利影响。研究表明:①农村人口流入城市,个体收入获得感显著提升,但其幸福感与流动之前并无明显变化,且增加了一定程度的不安全感,存在“福利博弈”;②城镇本地居民因流动人口的涌入促进了劳动职业分工,收入获得感较以前增强,但社交信任安全感稍有下降;流动规模与城镇本地居民的幸福感呈现正U 型状态,其影响由负转正的拐点为40.50%左右。结果表明,随着新型城镇化战略的不断推进和城市现代化治理能力的逐渐提升,城镇本地居民与流动人口平衡和谐共存局面也会最终达成。     

Income vulnerability of rural households in Bangladesh: a comparison between Bayesian and classical methods

The geographical location and the monsoon climate render Bangladesh highly vulnerable to natural hazards, deteriorating the country's socio-economic stability. This study is based on 500 randomly chosen rural households from the Household Income and Expenditure Survey [Bangladesh Bureau of Statistics, Planning Division, Ministry of Planning, Government of the People's Republic of Bangladesh, Dhaka, 2006]. The objectives are to estimate the income vulnerability of rural households and to check whether the Bayesian approaches (natural conjugate prior and non-informative prior estimates) have any superiority over the classical (feasible generalized least square (FGLS)) method. The poverty level, measured from the data, is 24%; whereas the vulnerability estimates, using FGLS, natural conjugate prior and non-informative prior are 31%, 69% and 82%, respectively. Vulnerability estimates by the Bayesian natural conjugate prior approach is found to have greater efficiency compared with FGLS and non-informative prior approaches.     

Infinite Variation Tempered Stable Ornstein–Uhlenbeck Processes with Discrete Observations

We investigate transition law between consecutive observations of Ornstein–Uhlenbeck processes of infinite variation with tempered stable stationary distribution. Thanks to the Markov autoregressive structure, the transition law can be written in the exact sense as a convolution of three random components; a compound Poisson distribution and two independent tempered stable distributions, one with stability index in (0, 1) and the other with index in (1, 2). We discuss simulation techniques for those three random elements. With the exact transition law and proposed simulation techniques, sample paths simulation proves significantly more efficient, relative to the known approximative technique based on infinite shot noise series representation of tempered stable Lévy processes.