台湾地区人口发展及“家庭计划”状况

一、台湾人口发展的四个阶段。第一阶段是1949年前后。1905年人口总数是312万人,1946年为609万人。1947—1949年由大陆迁台人员达124万人,使人口总数陡增到730万人。这时期的人口增长以迁移增长为主。第二阶段,1950—1971年人口自然增长最迅速时期。1964年人口总数达到1224万人,1971年达到1507万人。自然增长累计达709.8万人。第三阶段是1972年至七十年代末,人口增长速度放缓,净迁出增多,自然增长速度下     

含迁移要素的区域人口随机预测方法及其应用--以浙江省宁波市为例

以宁波市为例，基于宁波市“六普”与“五普”数据，首先利用年龄别死亡率对同批次队列人口进行年龄移算，即人口留存分析，对比2010年的实际人口数和无迁移模式下的封闭人口数之差，进一步测算两次普查期间分性别、年龄别人口的净迁移量和净迁移率。然后，将迁移率与出生率和死亡率整合，构建多要素随机人口预测模型，预测宁波市未来人口变化趋势，并评估迁移、死亡、出生三要素对人口变动的弹性影响效果。结果表明：人口净迁入对宁波市人口总量变化影响最大，而低死亡率和低出生率是未来50年加剧宁波市人口老龄化的主要原因。未来50年内，劳动力人口净迁入对降低宁波市人口老年负担系数的作用有限。鼓励夫妇生育二孩，优化人才引进与落户机制，尽快建立起应对高龄社会的公共服务体系尤其是长期照护体系，应是宁波市人口政策改革的当务之急。     

考虑人口省际和乡城迁移因素的陕西省城镇人口发展趋势预测

人口省际迁移与乡城迁移对城镇人口发展有重要影响。本文构建了包含人口省际和乡城迁移因素的动态预测模型,对2010-2060年陕西省城镇人口发展趋势进行预测。结果表明：第一,省际迁移和乡城迁移人口在年龄结构上呈倒V型分布,以劳动年龄人口为主,随时间推移,人口省际和乡城迁移趋势减缓。第二,在人口省际和乡城迁移的影响下,2047年陕西省城镇劳动年龄人口规模将达到峰值,之后回落,而少年儿童和老年人口规模在预测期内始终呈现增长趋势。第三,人口省际迁移和乡城迁移因素使陕西省城镇老龄化趋势得到显著改善。     

成都市人口变动态势的预测及其含义

本文以“等维灰数递补动态模型”对“人口发展方程”的流动人口预测部分作了修正,从而构建大城市人口态势综合预测模型,并对成都市2005~2030年包括流动—迁移人口在内的总人口及其结构变动作了预测。本预测结果的一般性政策含义是,在维持现行低生育水平不变的前提下,人口年龄金字塔的内缩,人口结构全面深度老化的趋势不因人口流迁而改变。为此,作者提出了相应的对策思考。     

我国城镇化与人口发展的前景

一、人口预测模型的探讨我国1990年的普查,提供了可信的人口性别、年龄构成资料,如果忽略国际迁移,祗须以生育序列、死亡序列的参数,就能用队列要素法(Cohort component Method)预测未来人口的规律与构成。90年代,我国人口死亡率已进入低水平时期,两性平均预期寿命分别达到67.7和71.2岁。因此,影响未来人口趋向最重要的因素是生育模式。为分析     

天津市人口分布特征研究

运用人口密度、人口结构化指数、罗伦斯曲线及空间自相关模型,分析了天津市人口空间分布特征,结果表明:天津市各区县人口总数差异较小,但各区县人口密度差异巨大;人口分布的不均衡指数为0.3893,集中指数为0.0390,人口分布集中化趋势明显;人口罗伦斯曲线表明全市40%左右的人口居住在占土地面积不足2%的行政区域中;天津市全局Moran’s I为0.4591,人口分布格局具有很强的空间正相关性;根据天津市人口密度、局部空间自相关分析结果,并耦合天津市市情,将天津市人口分布格局划分为三环结构。     

中国城镇、农村人口发展趋势预测

本文根据现阶段人口变动的情况，对中国未来人口发展进行了预测。人口预测的模型不仅考虑到城镇、农村在生育、死亡等方面的差异，而且也反映农村人口向城镇的动态迁移。在人口预测的生育模式上采用了总和递进生育率的指标，将妇女按所生孩次的结构分类。本文所作的预测为长期预测，对中国至２０５０年的总人口、城镇和农村人口发展以及人口的年龄结构作了较为详细的预测。     

人口知识

什么是人口年龄金字塔? 人口年龄金字塔是表现人口性别年龄结构的图形。把各年龄组的男女人数(一岁一组或五岁一组)或占人口总数的百分比,分别以不同长短的条形画在年龄轴的左右两侧,低年龄组在下,高年龄组在上,便得到一幅上尖下宽的图形,通称人口年龄金字塔或人口金字塔。     

多维家庭人口预测模型的建立及应用

本文建立了多维的家庭人口预测模型。该模型可用于同时预测家庭户以及人口的规模、结构、特征及分布，并保证人口事件（如结婚、离婚、再婚子女离家等）的发生在男性人口与女性人口之间的一致性以及在父母辈与子女辈之间的一致性。与国外学者近年提出的多维宏观家庭户预测模型相比，本文建立的模型的一个明显优点是无需从专项家庭抽样调查得到的家庭户类型转换概率数据，只需通常的生育、死亡、婚姻等人口数据。与传统的户主率方法不同，本文模型将家庭户预测与未来生育、死亡、婚姻等人口事件发生率紧密地联系起来，可同时预测核心与三代家庭户，既可用于中国等发展中国家，又可用于西方发达国家     

拉丁美洲地区的人口发展和人口政策

近一个世纪以来,拉丁美洲地区的人口一直持续而迅速地增长,人口总数已由1900年的7,400万增加到1981年的3.6亿,在世界总人口中所占比重也由4.4％增至8.1％。就人口增长率来说,1900年至1950年的人口年均增长率为1.6％,和大洋洲并列世界第一;在1950年至1975年的二十五年中,年均增长率高达2.8％,居世界各大洲首位,远高于世界的平均数（1.9％）,成为全世界人口增长最快的地区。根据预测,2000年时拉丁美洲的总人口将达5.6亿多,而到二十一世纪末实现人口稳定发展（出生率和死亡率相等）,届时将比现有人口增加近三倍,达13亿多。 面对人口的急剧增加,特别是人口剧增所带来的一系列社会经济问题,拉美各国政府逐渐认识到了控制人口的必要性,同时也相继制定并采取各自的人口政策。本文拟对拉美地区     

Migration, fertility, and aging in stable populations

Fertility is below replacement level in all European countries, and population growth is expected to decline in the coming decades. Increasing life expectancy will accentuate concomitant aging of the population. Migration has been seen as a possible means to decelerate aging. In this article, I introduce a stable, open-population model in which cohort net migration is proportional to births. In this case, the migration-fertility trade-off can be studied with particular ease. I show that although migration can increase the growth rate, which tends to make the age distribution younger, it also has an opposite effect because of its typical age pattern. I capture the effect of the age pattern of net migration in a migration-survivor function. The effect of net migration on growth is quantified with data from 17 European countries. I show that some countries already have a level of migration that will lead to stationarity. For other countries with asymptotically declining population, migration still provides opportunities for slowing down aging of the population as a whole.     

Changing patterns of migration between metropolitan and nonmetropolitan areas in the United States: Recent evidence

Data from the 1975 Current Population Survey confirm that, during 1970–1975, there was a reversal of the traditional net migration stream between metropolitan and nonmetropolitan areas in the United States. During this period, there was net in-migration of 1,600,000 persons to nonmetropolitan areas, in contrast to net out-migration of 350,000 persons from these areas in 1965–1970. Reversal was caused by a 12 percent decrease in the number of nonmetropolitan out-migrants and a 23 percent increase in the number of SMSA residents moving to nonmetropolitan territory over 1965–1970 levels. While some changes in the size of migration streams were due to changes in age structures and population bases in metropolitan and nonmetropolitan areas, they were caused primarily by real shifts in outmigration propensities at practically all ages in both areas.     

Stabilization,birth waves,and the surge in the elderly*

Substantial regularities characterize the transition to stability that follows a shift from one set of vital rates to another. The new vital, rates interact with the population's initial age composition and generate birth waves whose amplitude and attenuation depend on the ratio of ultimate to initial growth and on the new pattern of stable net maternity. A greater change in growth and a later stable net maternity pattern produce larger fluctuations in the number of births. Stabilization begins at the youngest ages and proceeds upward. Sixty years after the shift, the birth waves have largely disappeared and the proportion under age 15 approximates the stable level implied by the new rates. Those patterns are manifest in the stabilization of both observed and Coale‐Demeny model stable populations.

When fertility falls, the new stable population has a larger fraction at all ages above (approximately) 30, with greater changes characterizing the extremes of life. Fifteen years after the fall, there is a trough in the number at ages 0–14. Sixty years after the fall, when the largest pre‐decline cohort is age 60–74 and the smallest post‐decline cohort is age 45–59, there is a surge in the relative size of the elderly population. Thus after two generations, the birth waves produced by a rapid decline in fertility accentuate the effects of population aging.     

Estimates of coverage of the population by sex,race, and age in the 1970 census

Several estimates of total net underenumeration and of net census errors by sex, race (white, Negro-and-other-races, Negro), and age (five-year groups) in the 1960 and 1970 Censuses, for the total population of the United States, derived by the methods of demographic analysis, are presented. The different data, procedures, and assumptions employed in developing the various estimates are described briefly, and the findings are then discussed in terms of a”preferred” set of estimates. The preferred set of estimates of corrected population for 1970 combines estimates for persons under age 35 based directly on birth, death, and migration statistics, estimates for females aged 35 to 64 based on the Coale-Zelnik estimates (white) for 1950 or the Coale-Rives estimates (Negro) for 1960, estimates for males aged 35 to 64 based on the use of expected sex ratios, and estimates for the population 65 and over based on”Medicare” enrollments and expected sex ratios. These estimates indicate an overall net underenumeration of 5.3 million persons or 2.5 percent in 1970, as compared with 5.1 million or 2.7 percent in 1960, and a net underenumeration of 1.9 percent for whites and of 7.7 percent for Negroes in 1970, as compared with 2.0 percent and 8.0 percent, respectively, in 1960. As in 1960, undercoverage in 1970 was greatest for Negro males (9.9 percent); net error rates exceeded 12 percent in each age group 20 to 49 and reached 17 to 19 percent at ages 25 to 44. All sex-race groups showed marked increases between 1960 and 1970 for children under ten and marked declines at ages ten to 24. Equally reliable estimates of population coverage cannot be prepared for states and smaller geographic units or for the population of Spanish ancestry.     

Population dynamics in Germany: the role of immigration and population momentum

The effects of changes in rates of mortality, fertility, and migration depend not only on the age-specific patterns and levels of these rates, but on the age structure of the population. In order to remove the influences of the age structure and concentrate on the effects of the demographic rates themselves, a common practice is to analyze the influences of the rates for a standard age structure. This paper analyzes current and future population changes in Germany, using a stationary population equivalent model (SPE) that shows long-term effects of current fertility, mortality, and international migration patterns. Results indicate that the German population will eventually decline because of below replacement fertility, if net immigration does not counteract this decrease. This means, for instance, that the long-term stationary population levels for Germany will decrease by approximately 6.5 million during a decade in which current fertility, mortality, and international migration levels prevail. The paper also reports how various other assumptions for mortality, fertility, and international migration affect the SPE model for Germany.     

Evaluation of Alternative Cohort-Component Models for Local Area Population Forecasts

It is generally accepted by demographers that cohort-component projection models which incorporate directional migration are conceptually preferable to those using net migration. Yet net migration cohort-component models, and other simplified variations, remain in common use by both academics and practitioners because of their simplicity and low data requirements. While many arguments have been presented in favour of using one or other type of model, surprisingly little analysis has been undertaken to assess which tend to give the most accurate forecasts. This paper evaluates five cohort-component models which differ in the way they handle migration, four of which are well known, with one—a composite net migration model—being proposed here for the first time. The paper evaluates the performance of these five models in their unconstrained form, and then in a constrained form in which age–sex-specific forecasts are constrained to independent total populations from an extrapolative model shown to produce accurate forecasts in earlier research. Retrospective forecasts for 67 local government areas of New South Wales were produced for the period 1991–2011 and then compared to population estimates. Assessments of both total and age-specific population forecasts were made. The results demonstrate the superior performance of the forecasts constrained to total populations from the extrapolative model, with the constrained bi-regional model giving the lowest errors. The findings should be of use to practitioners in selecting appropriate models for local area population forecasts.     

Change, continuity or cycles: The population turnaround in New South Wales

This study examines population flows from Sydney and other regions to perimetropolitan and coastal areas of New South Wales, the two main foci of the population turnaround since 1971. It uses census internal migration statistics for the five intercensal periods between 1971 and 1996, and estimated resident population statistics between 1997 and 2000. Fluctuating trends are described with respect to variations in age structures of migration flows and net migration gains by SLAs in coastal areas over time. Evidence of fluctuating trends is evaluated in relation to population structure change and local socio-economic multipliers in turnaround areas. The turnaround is far mor than a net migration gain from large metropolitan areas; it is also associated with interregional migration which avoids metropolitan areas, and which is at least in part environment- and amenity-related. The experience of some other countries, such as the USA where net migration reversals in population turn-around regions have occurred, has not been replicated in Australia. While elements of explanation for the complex cumulative causation process of the population turnaround in Australia are discussed, including the issues of fluctuating or cyclical trends, much more understanding of the economic and social factors involved is required.     

Effects of migration on the educational levels of the black resident population at the origin and destination, 1955–1960 and 1965–1970

Using the 1960 and 1970 census data, this paper analyzes the net effects of the interregional migration of black males on the educational levels of the resident black male population at the regions of origin and destination. Significant variations are observed in the educational selectivity of out-migrants from each region, by region of destination. Comparing the educational levels of the return migrants to the South with those of the resident population in the nonsouthern regions provides no evidence that the return migrants are "failed" migrants. The net effect of interregional migration on the educational levels of the black male resident population at the regions of origin and destination is insignificant in most age groups, for both the 1955--1960 and 1965--1970 periods. In particular, in-migration from the South to nonsouthern regions has little effect on the educational levels of the resident population in most age groups. In fact, for nonsouthern regions, out-migration is more detrimental to the educational level of the resident black male population than is in-migration from the South. Furthermore, the net effect of interregional migration has declined from the 1955--1960 period to the 1965--1970 period.     

Estimation of interprovincial migration for Canada from place of birth by residence data, 1951–1961

In Canada, unlike many other countries, birth-residence data by age and sex are available in each of the decennial censuses from 1931 to 1961 which permit the estimation of intercensal net migration for the provinces and regions. After a brief discussion of the basic measures of migration from birth-residence data the paper focusses on the problems and procedures in estimating interprovincial net migration, 1951–1961 for Canada using “the place of birth survival ratio method, ” and it evaluates the estimates thus obtained. The evaluation of the estimates, taking into consideration the inherent limitations of the method and its merits compared with period migration estimates by the census survival ratio method and life table survival ratio method, suggests that the net migration estimates for the Canadian born by the place of birth survival ratio method are probably more reliable than those by the other two methods. One striking finding was that the net migration curves by age obtained from the census survival ratio and place of birth survival ratio estimates were smoother than the curve obtained with the use of the more accurate life table survival ratios. Furthermore, whatever the relative accuracy of net migration may be, the birth-residence approach is capable of furnishing more details about the net migration of the native born than by the standard survival-ratio methods. For the population under age 10 intercensal estimates were directly derived from the place of birth and residence distributions by age.     

Southern Negro Migration: Social And Economic Components Of An Ecological Model

This paper considers social and economic correlates of age-specific 1950-1960 net migration of Negro males from a sample of 150 southern counties. A model is developed with five components: (1) economic activity and urbanization, (2) white traditionalism, (3) demographic and ecological pressure, (4) nonwhite poverty, and (5) nonwhite home ownership. The dominant migration forces, as evidenced by correlations with component indicator variables, are the "pull" factor of change in nonprimary industrial employment, the "push" factor of population pressure in the nonwhite rural-farm sector, and the "push" of white traditionalism. However, the significance of model components varied when analyzed along age and industrial development continua. In the younger age groupings, industrial employment growth, population pressure, and white traditionalism were dominant migratory forces while in the older age groupings, industrial employment growth and non-home ownership were most significant. For Negro males in agricultural counties, the major migration propellents appeared to be the "push" of population pressure in the rural farm sector and non-ownership of homes. On the other hand the statistical explanation for Negro migration in more industrialized southern counties rests primarily with the "pull" of increased employment in non-primary industries along with population pressure. The importance of the findings for migration theory is discussed.