Determining the birth function for an age structured population

This paper deals with an inverse problem in age‐structured population dynamics, namely the recovery of the unknown birth function from the additional or overposed data consisting of the total population over a time interval equal to the maximum life span of the species. Conditions on the data are given to guarantee the existence and uniqueness of a solution, and the question of continuous dependence of the birth function on the data is addressed. Some numerical simulations are presented to indicate that one can in fact use the methods of the paper to reconstruct the birth function.     

中国人口终身迁移状况分析

“出生地”是用来收集人口迁移信息最常用的调查项目之一。中国以往的人口普查中一直缺少这一调查项目 ,这使得利用出生地资料对人口迁移状况进行分析在国内一直是个空白。中国第五次人口普查在中国人口普查史上首次调查了人口的出生地信息。本文主要根据第五次人口普查提供的出生地资料 ,对中国各省人口的终身迁移水平、流向以及不同年龄人口的终身迁移状况进行了初步分析。     

中国人口年龄结构变动对出生率的影响研究

本文利用相关年份的《中国统计年鉴》和人口普查数据,根据粗出生率与总和生育率的关系与特征,构建了人口年龄结构系数及其对粗出生率变动影响的贡献率指标,分析了建国以来人口年龄结构变动对出生率的影响。研究发现：1949—1979年,人口年龄结构变动对出生率的影响很小;1980—1993年,人口年龄结构变动对出生率的影响迅速上升,年龄结构的贡献率增大;1994—2008年,人口年龄结构变动对出生率的影响趋于下降,人口惯性势能在减弱;2009—2011年,受80—90年代出生高峰的影响,人口年龄结构变动对出生率的影响再次凸显,年龄结构的贡献率迅速增大。从年龄别生育率逐年下降的特点,也可以证明近年推动我国人口增长的力量主要是由于年龄结构带来的惯性增长。     

对2000年人口普查出生性别比的分层模型分析

本文对以往出生性别比研究中的若干观点进行了学术评论,并讨论了个别经验统计分析中的方法问题。在此基础上,本文应用非线性分层模型将2000年全国人口普查1‰数据和1999年的地区级生育政策数据结合起来对出生性别比失调的影响因素进行了初步分析。结果表明,育龄妇女现有子女数量及性别和一些社会特征对出生性别比存在单独的影响,并且肯定了生育政策既存在对出生性别比的直接影响,也通过其与妇女以往生育结果以及其他社会特征之间的交互效应来影响出生性别比。     

邓小平人口思想探析

邓小平理论博大精深,邓小平人口思想则是其有机组成部分之一,通过对邓小平人口思想的形成和历史进行研究,揭示出邓小平人口思想的核心内容和主要特点,对进一步指导我国的人口和计划生育工作有积极意义。     

土地制度创新与欠发达地区农村的人口控制

本文主要研究了土地产权制度安排与计生工作的相关性,首先从定点调研社区的人地关系矛盾入手;然后,回顾了不同的土地制度对人口发展的相关性影响,重点阐述土地产权制度控制人口的工作机理,分析社区目前和未来影响土地产权制度发挥控制人口作用的因素;最后,从制度创新的功能和作用的角度,提出完善人口控制机制的建议和措施。     

中国出生性别比偏高及未来女性赤字预测

1980年代以来,中国人口出生性别比开始偏高且持续增高,2000年出生性别比已经达到116.9。出生性别比偏高不仅表现在分孩次的差异上,而且还表现出了明显的地区分布特征。本文利用“五普”数据资料为基期,对1980年后出生、并受出生性别比持续升高影响的人口进行预测,分析30年间的分城乡、分年龄的女性赤字规模及其变化趋势。     

Developing strategies for deriving small population fertility rates

Many agencies require population estimates and projections by ethnic group. These projections need ethnic-specific, age-specific fertility rates (ASFRs) but their inclusion is challenging since ethnicity is not recorded at birth registration. In this paper maternity data are used in a case study of electoral wards in Bradford, West Yorkshire, to develop fertility rates for small populations for a 1991 based projection. The challenge is to capture local variations in fertility by ethnic group when data are sparse. Small areas were grouped together using cluster analysis to define combinations with similar sociodemographic and fertility experiences so that sparse data could be aggregated to estimate reliable ethnic-specific fertility rates. For comparison, the data were aggregated into the 1991 Office for National Statistics area type classification. Fertility rates by single year of age for all area types were smoothed using the Hadwiger function. For the White ethnic group there were sufficient births to create ethnic-specific, ward-level ASFRs. For other ethnicities grouping of areas was necessary. The accuracy of the ASFRs in predicting births was assessed using mean absolute percentage error. Results show that for some minority groups district-level ethnic-specific fertility rates produced the most accurate birth estimates even though they were based on a larger area. This implies that rates created may be informative about the local area for White ethnic type but not in the same way for smaller ethnic groups. In terms of grouping strategies we recommend that existing classifications are assessed to determine how well variations in rates are stratified before embarking on a custom scheme. Where population sub-groups are small in some areas, it may be more reliable to use rates derived for larger areas and apply these to local populations. Inevitably, the rates used in a projection are a compromise but hopefully will still capture important dimensions of population change.     

对近年来中国人口统计学学科发展状况的评述

本文对2002年下半年以来中国人口数据和人口统计分析方法的状况进行描述、归纳和评述,其中包括对普查数据质量的分析、生育率分析、死亡率分析、出生性别比分析、流动人口分析、人口老龄化研究和人口预测及其方法研究,以及对学科发展态势的评价。     

民族地区出生人口性别比状况分析及对策研究

本文以"四普"、"五普"数据为基础,结合近年来湘西州出生人口性别比调查数据,对湘西州少数民族人口出生性别比状况进行分析,提出治理民族地区出生人口性别比失衡的对策,为民族地区人口与经济社会的和谐发展做出思考。     

Development of birth registration and birth statistics in the United States

The registration of vital events in the United States has always been under the authority of State and local areas. The preparation of national birth statistics has been made possible through a co-operative working arrangement between the Federal Government and the States. This paper traces the development of registration systems in the United States from colonial days to the present period. The absence of adequate registration systems throughout the country, during the nineteenth century, led to the use of data collected in the decennial population censuses of 1850–1900 for estimating birth rates. This procedure was abandoned because of the unreliability of the results. Steps leading to the formation of the national birth-registration area in 1915, when it included ten States and the District of Columbia, and. activities resulting in its completion in 1933 are discussed.

A major portion of the paper outlines the nation-wide test of birth-registration completeness conducted in 1940 in conjunction with the decennial census of population. Important results of the test are presented, and the methodology is explained. A similar test is being carried out in 1950. Data derived will be used to focus attention on local areas requiring registration promotion. Correction factors for statistical series based on registered events will also be obtained. The final section of the paper indicates the steps States are taking to improve quality of reporting on the birth record. Changes in the content of the standard certificate of live birth since 1915 are summarized and the statistics tabulated from birth certificates detailed.     

An alternative formulation of the birth function in a two-sex model

The inconsistency in Lotka's stable population model (two different intrinsic growth rates for the two sexes) arises from the fact that he considers two equations (for male and female births), and not because his equation for one sex does not involve the other. Many authors in the past have erroneously put emphasis on the latter point and modified Lotka's equations for male and female births. Since sex ratio at birth is constant, two independent equations for male and female births cannot exist. The correct approach is to attempt to form an equation for all births. The author followed this approach in his earlier works on the problem, but his birth functions were formulated from axiomatic considerations. The present paper provides a new birth function which has an intuitively appealing physical interpretation, and for which the interaction between the sexes is empirically determined from the data.     

Short-term fluctuations in fertility and economic activity in Israel

This paper investigates the relation between fluctuations in fertility and in economic activity in Israel over the period 1950–1970. The paper opens with some comments on the theoretical basis for expecting procyclical behavior of fertility. This is followed by analysis of annual data of total fertility, unemployment, GNP and an index of industrial production. Total fertility tends to respond to the cyclical indicators among Jews from Europe and America, those born in Israel and those from Asian and African countries, but the response is larger among the former. Cyclical response can be discerned also in the fertility of the non-Jewish population. The performance of the alternative cyclical indicators is compared. Some examination of data on marriage suggests that the cyclical response of birth is not just a reflection of the cyclical response of marriage. In the annual data there is a tendency for.Jewish fertility to be more related to the contemporaneous cyclical indicator than the lagged indicator, while the reverse is true for the non-Jewish population. Examination of quarterly and monthly data for a shorter period corroborates this finding. Many factors are involved in determining the lag between an observed cyclical indicator and observed birth; it is being conjectured that the prevalence of abortions in the Jewish population is one contributing factor to the difference in the lag between.Jews and Arabs.     

General growth balance method: A reformulation for populations open to migration

This paper proposes a reformulation of the general growth balance method for estimating census and registration completeness so as to make it applicable even to populations that are affected by migration. It also discusses a new procedure of line fitting that could be useful in countries where the input data are severely affected by age misreporting. The method is applicable to countries where data on age distribution of the population are available for two points in time from either censuses or surveys. Following closely the original proposal of Brass, it involves adjusting the 'partial' birth rates for age-specific disturbances from growth and migration rates. Beyond correcting the death rates, the method is useful in inferring the relative completeness of the censuses, and in deriving a robust estimate of birth rate under certain conditions. The application of the method is illustrated using the example of the male population of the Indian state of Uttar Pradesh for the period 1981 to 1991.     

General growth balance method: A reformulation for populations open to migration

This paper proposes a reformulation of the general growth balance method for estimating census and registration completeness so as to make it applicable even to populations that are affected by migration. It also discusses a new procedure of line fitting that could be useful in countries where the input data are severely affected by age misreporting. The method is applicable to countries where data on age distribution of the population are available for two points in time from either censuses or surveys. Following closely the original proposal of Brass, it involves adjusting the ‘partial’ birth rates for age-specific disturbances from growth and migration rates. Beyond correcting the death rates, the method is useful in inferring the relative completeness of the censuses, and in deriving a robust estimate of birth rate under certain conditions. The application of the method is illustrated using the example of the male population of the Indian state of Uttar Pradesh for the period 1981 to 1991.     

Geographic Ancestry and Cause-specific Mortality in a National Population

There are marked differentials in mortality risks across regions in Finland. No exhaustive explanation to this variation has been provided, however. The aim of this paper is to analyse how geographic ancestry, as proxied by persons’ birth region and population group, interrelates with cause-specific mortality risks. Focusing on people aged between their mid-thirties and late-forties, we use longitudinal population register data that offer opportunities to account for variables that represent both persons’ social background and their own social status at young adult age. Results of Cox proportional hazard models say that these variables have substantial effects on mortality of different causes, but only a marginal impact on the variation in death rates by birth region and population group. The geographic mortality pattern is found to be specifically prominent for causes of death that are fairly unrelated to persons’ lifestyles. Our findings suggest that genetic predisposal as expressed in terms of geographic ancestry might play a relevant role in understanding mortality variation within the population of Finland.     

江苏太仓市低人口生育率原因剖析

江苏太仓持续降低的人口生育率引起人口学界越来越多学者的关注。该地区低人口生育率并不是人口生育过程中的波动造成的,而是呈现出比较稳定的逐年下降的趋势。本文通过历史数据剖析了该地区低人口生育率的成因,并依据在该市的实地调研数据,剖析太仓市妇女二胎生育意愿,预测未来太仓未来人口生育率的变动。     

论青年女性流动人口初育间隔与人口控制——来自厦门流动人口家庭问卷调查的启示

青年女性流动人口实际生育行为的控制对于人口规模与结构的控制,起着至关重要的作用。而生育时间的选择作为影响流动人口生育实践的一个重要因素,体现在对各孩次生育间隔的控制上。本文在描述分析的基础上,应用Cox比例风险模型,主要对厦门市青年女性流动人口初育间隔的影响因素进行估计和检验,并在总结分析的基础上对流动人口控制问题提出几点对策思考。     

广东妇女生育水平的变化及影响因素分析

根据第五次人口曾查资料,本文详细描述了广东妇女生育水平的现状。并从实际出发,对影响广东省生育水平和生育机制的农村生育模式,生育孩次构成,文化水平和职业构成等四个重要因素进行分析。最后,就稳定广东省低生育水平,提高人口科学管理等问题提出三点建议。     

中国双生子出生性别比研究

人口自然出生性别比是分析和评价人口出生性别比偏离的重要指标,中国对人口自然出生性别比的研究一直比较缺乏。人的出生性别比正常范围为102～107,国内一般都是以其上限作为标准判断人口出生性别比偏高的程度。但是这种做法是值得商榷的。利用第四次全国人口普查资料中的双生子信息探讨双生子出生性别比特征。研究表明,中国1989年双生子出生性别比为104.87,在女性主要生育年龄阶段生育的双生子出生性别比是相当稳定的,比较接近自然状态下的出生性别比。相比较而言,中国人口出生性别比不仅普遍偏高,而且随女性生育年龄变化的模式也不相同。