首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
Levels and patterns of internal migration in Europe: A cohort perspective   总被引:1,自引:0,他引:1  
Europe displays important variations in the level of internal migration, with a clear spatial gradient of high mobility in northern and western Europe but lower mobility in the south and east. However, cross-national variation in levels of internal migration remains poorly understood, because it is analysed almost exclusively using cross-sectional data and period measures. This paper seeks to advance understanding of cross-national variation in migration levels in 14 European countries by drawing on a recently proposed suite of migration cohort measures, coupled with internationally comparable retrospective residential histories. It shows that differences in migration levels are mainly attributable to variation in the extent of repeat movement, which is underpinned by the differences in mean ages at first and last move that together delineate the average length of migration careers. Cohort analysis provides a robust foundation for exploring the demographic mechanisms underpinning variation in migration levels across countries and over time.  相似文献   

2.
P. S. Nair 《Demography》1985,22(1):133-142
Two models, hierarchical in terms of input data requirements, are proposed to estimate place-to-place gross migration flows during a specified time period. In the first, the input data required are lifetime migration flows and the marginal totals of period migration, usually available from national censuses. The estimational algorithm is a ‘bi-proportional adjustment’ technique (and its variant) that assumes structural similarity between lifetime and period migration flows. The second model is designed to account for possible structural deviations in recent migratory patterns. Calibration of the procedure to replicate Indian and Korean data confirms high validity of estimation.  相似文献   

3.
Parity progression measures are uniquely suited to the study of fertility in China, because Chinese policies and programmes focus so closely on parity and birth order. In this paper we present period parity progression ratios for China and its urban and rural areas for the years 1955–81, using the birth history data from the one-per-thousand fertility survey of 1982. Our period parity progression ratios differ from those introduced by Henry in that they provide an overall level of fertility which may be compared with measures based on age-specific birth rates. We compare the two measures empirically for China, finding both similarities and divergences, and then analyse the relation between them. It is suggested that, where fertility is low and fluctuating, as in China, the parity-progression-based measures provide a substantially truer picture of fertility levels and trends than do age-based measures.  相似文献   

4.
Using longitudinal data from three demographic surveillance systems (DSS) and a retrospective cohort study, we estimate levels and trends in the prevalence and incidence of orphanhood in South Africa, Tanzania, and Malawi in the period 1988-2004. The prevalence of maternal, paternal, and double orphans rose in all three populations. In South Africa - where the HIV epidemic started later, has been very severe, and has not yet stabilized - the incidence of orphanhood among children is double that of the other populations. The living arrangements of children vary considerably between the populations, particularly in relation to fathers. Patterns of marriage, migration, and adult mortality influence the living and care arrangements of orphans and non-orphans. DSS data provide new insights into the impact of adult mortality on children, challenging several widely held assumptions. For example, we find no evidence that the prevalence of child-headed households is significant or has increased in the three study areas.  相似文献   

5.
As an ordinary life table follows a closed group from birth to the death of its last member, a labor force status life table follows a closed group through life and through the statuses “in the labor force” and “not in the labor force.” Using data from the January 1972 and January 1973 Current Population Surveys, two types of labor force status life tables were calculated for the United States, 1972. One type was a conventional working life table (for males) which started with an ordinary life table and partitioned the life table population into labor force statuses using age-specific proportions in the labor force. The other type was an increment-decrement table, prepared for both males and females, which was calculated so as to be consistent with the rates of labor force accession and separation implied by the data. Increment-decrement labor force status life tables are generally preferable to conventional working life tables. They reflect the implications of a clearly specified set of behavioral rates, provide detailed measures of the flows between labor force statuses, do not introduce seriously biasing approximations into the calculation of summary measures of labor force experience, and can be applied to female data as easily as male data. In practice, incrementdecrement labor force status life tables can be calculated from current and retrospective data generated by a single labor force survey. The increment-decrement labor force status life tables for the United States, 1972 reflected the extent to which the labor force participation of males exceeded that of females, but indicated that, on the average, half a woman’s lifetime between the ages of 16 and 65 was spent in the labor force. There were marked differences in the proportions, by age, of males and females in the labor force, with the male pattern rising to a single, flat peak and the female pattern being bimodal. Nonetheless, the two sexes shared similar age patterns in the proportions changing, or not changing, their labor force status.  相似文献   

6.
Abstract Statistics ofpersons classified jointly by county of birth and county ofresidence have been published in the England and Wales census volumes since 1851 and the present study draws mainly on these data. A group of persons recorded in a census as natives of county A and residents of county Bare sometimes referred to as lifetime migrants from county A to county B. Statistics of lifetime migrants have often been used in studies of internal migration but these have one great disadvantage. The number of lifetime migrants from A to B does not relate to a specific period of time. It is impossible, for example, in such studies to consider the association between specific migration streams and differential economic activity. An attempt is made in this study to transform lifetime migration data into intercensal migration streams. Some of the results are presented and the most significant migration patterns during the period 1851-1951 are described.  相似文献   

7.
This study tests the influence of environmental changes on migration in Burkina Faso. It describes individual migratory pathways in the 1960–1999 period in Burkina Faso, using environmental typologies of origins and destinations based on rainfall variations and land degradation. The study links data from a national longitudinal (retrospective) survey with fine resolution rainfall data and land degradation data. Results suggest that environmental factors influence, but in different ways, both the probability to out-migrate and the selection of a destination once the migration decision has been made. Migration seems to be more influenced by a slow-acting process such as land degradation than by episodic events such as droughts.  相似文献   

8.
未来全国和不同区域人口城镇化水平预测   总被引:10,自引:0,他引:10  
城镇化将是我国未来几十年社会经济发展的动力之一。从人口学的角度讲,在加速城镇化过程中,人口三大因素,即出生、死亡、迁移的变化中,人口城乡迁移将是核心问题。本文在城镇化发展的中方案假设下,利用ⅡASA的模型对全国和地区未来30年人口城镇化水平进行预测。结果显示了全国和不同区域的城镇化长期趋势;揭示了城乡间的迁移和农村居民身份的改变,是城镇地区人口高速增长的重要因素。伴随城镇化的加速,农村地区人口老龄化速度快于城市。  相似文献   

9.
Statistics ofpersons classified jointly by county of birth and county ofresidence have been published in the England and Wales census volumes since 1851 and the present study draws mainly on these data. A group of persons recorded in a census as natives of county A and residents of county Bare sometimes referred to as lifetime migrants from county A to county B. Statistics of lifetime migrants have often been used in studies of internal migration but these have one great disadvantage. The number of lifetime migrants from A to B does not relate to a specific period of time. It is impossible, for example, in such studies to consider the association between specific migration streams and differential economic activity.

An attempt is made in this study to transform lifetime migration data into intercensal migration streams. Some of the results are presented and the most significant migration patterns during the period 1851–1951 are described.  相似文献   

10.
Migration is the most difficult component of state and local population growth to forecast accurately because it is more volatile than either births or deaths, and subject to much larger fluctuations within a short period of time. In addition, migration rates can be based on several different measures of migration and the base population. The choice of the appropriate base population has received little attention from demographic researchers, but can have a tremendous impact on population projections. In this article, I develop three different models for projecting migration, each using a different denominator for migration rates. Population projections for ten states are made, using identical data and cohort component techniques, except for the different formulations of migration rates. Differences among the three sets of projections are noted, and conclusions are drawn regarding their usefulness as forecasts of population growth.  相似文献   

11.
We describe a regression-based approach to the modelling of age-, order-, and duration-specific period fertility, using retrospective survey data. The approach produces results that are free of selection biases and can be used to study differential fertility. It is applied to Demographic and Health Survey data for Ethiopia, Kenya, Tanzania, and Zimbabwe to investigate differential trends in fertility by education. Parity progression fell and the intervals following each birth lengthened between the 1970s and 2000s in all four countries. Fertility fell most among women with secondary education. In contrast to other world regions, postponement of successive births for extended periods accounted for much of the initial drop in fertility in these African countries. However, family size limitation by women with secondary education in Ethiopia and Kenya and longer birth spacing in Zimbabwe also played significant roles. Thus, birth control is being adopted in Eastern Africa in response to diverse changes in fertility preferences.  相似文献   

12.
The debate surrounding the use of period, cohort, and tempo-adjusted measures has framed most of the recent studies evaluating the utility of macro-level fertility indicators. Period measures are susceptible to distortions, due to birth timing changes, but there is currently no universally accepted adjustment technique. Recent comparative analyses have offered some insights but only as applied to the low-fertility developed world setting. The utility of different types of measures in the high fertility context is unclear. Furthermore, regional variation in the pace of fertility transition is characteristic of many less developed countries and is rarely incorporated into macro-level analyses. The purpose of this analysis is to evaluate macro-fertility indicators at the regional and national levels in a high-fertility country, Guatemala, using the four most recent survey data sets. The results support the use of macro-level period indicators and adjusted period indicators of fertility in developing country contexts.  相似文献   

13.
Past national surveys regarding birth expectations have usually been restricted to currently married women, a fact which has led demographers to question the usefulness of these data. Because the June 1976 Current Population Survey includes the expectations of all women in a cohort regardless of marital status, it provides the data needed to evaluate biases due to restricted survey universes. At older ages, where there are substantial differences in lifetime expectations between currently married and single women, there are relatively few single women; at younger ages, however, where the proportion of single women in a cohort is relatively large, the differences in expectations are small. This counterbalancing effect makes the lifetime birth expectations of currently married women a close approximation of all women in a cohort. The analysis also indicates that the observed intracohort declines in lifetime birth expectations since 1967 were due largely to the addition at subsequent survey dates of previously unmarried women; nevertheless, some “true” cohort declines also seem to have occurred.  相似文献   

14.
Using discrete-time survival models of parity progression and illustrative data from the Philippines, this article develops a multivariate multidimensional life table of nuptiality and fertility, the dimensions of which are age, parity, and duration in parity. The measures calculated from this life table include total fertility rate (TRF), total marital fertility rate (TMFR), parity progression ratios (PPR), age-specific fertility rates, mean and median ages at first marriage, mean and median closed birth intervals, and mean and median ages at childbearing by child’s birth order and for all birth orders combined. These measures are referred to collectively as “TFR and its components.” Because the multidimensional life table is multivariate, all measures derived from it are also multivariate in the sense that they can be tabulated by categories or selected values of one socioeconomic variable while controlling for other socioeconomic variables. The methodology is applied to birth history data, in the form of actual birth histories from a fertility survey or reconstructed birth histories derived from a census or household survey. The methodology yields period estimates as well as cohort estimates of the aforementioned measures.  相似文献   

15.
A nation’s population is redistributed through migration flows and counterflows between its constituent subnational areas, resulting in a geographical pattern of net migration gains or losses which may change from one time period to another. Migration effectiveness is the indicator commonly used to measure net migration as a proportion of gross migration turnover for any territorial unit. This paper explores the effect of net migration in two different countries, Australia and the United Kingdom, using measures of migration effectiveness computed from period-age migration data sets for a system of city regions assembled for four consecutive five-year periods in each country. While the evidence suggests that the overall effectiveness of net migration has declined over the 20-year period in both countries, marked similarities and contrasts are apparent in the spatial patterning of migration that together provide useful analytical insights into the changing space economies of the two countries.  相似文献   

16.
Jampaklay A 《Demography》2006,43(4):711-725
This study examines the effects of migration on marital timing in Thailand between 1984 and 2000 using prospective and retrospective survey data from Nang Rong. In contrast to previous results in the literature, event-history analysis of the longitudinal data reveals a positive, not a negative, effect of lagged migration experience on the likelihood of marriage. The findings also indicate gender differences. Migration's positive impact is independent of other life events for women but is completely "explained" by employment for men.  相似文献   

17.
Timing effects and the interpretation of period fertility   总被引:1,自引:0,他引:1  
Schoen R 《Demography》2004,41(4):801-819
Low fertility levels and later childbearing in many developed countries have reinvigorated the debate between period and cohort perspectives on fertility and on the meaningfulness of the period total fertility rate (TFR). Here, fertility-timing effects are defined as level changes in period fertility that do not reflect level changes in the completed fertility of cohorts. That definition leads to the average cohort fertility (ACF) as a measure of period fertility adjusted for timing effects. In an influential paper, Bongaarts and Feeney (1998) presented an alternative approach and a different measure, TFR*, to adjust for timing effects. Here, the two measures are compared. In the context of model populations, the ACF performs well, reflecting an average of the fertility of the active cohorts. The Bongaarts-Feeney TFR*, however, is frequently unreliable and can be erratic when there are cycles in period timing. When applied to twentieth-century U.S. experience, the TFR* behaves like a period measure and yields adjustments that are often wide of the mark. The ACF shows the stability associated with cohort measures and quantifies the substantial impact that timing effects had during the "birth dearth" of the 1970s. The period TFR reached a low of 1.74 in 1976, but the ACF never went below 2.06 during the 1970s.  相似文献   

18.
We estimate trends and racial differentials in marriage, cohabitation, union formation and dissolution (union regimes) for the period 1970–2002 in the United States. These estimates are based on an innovative application of multistate life table analysis to pooled survey data. Our analysis demonstrates (1) a dramatic increase in the lifetime proportions of transitions from never-married, divorced or widowed to cohabiting; (2) a substantial decrease in the stability of cohabiting unions; (3) a dramatic increase in mean ages at cohabiting after divorce and widowhood; (4) a substantial decrease in direct transition from never-married to married; (5) a significant decrease in the overall lifetime proportion of ever marrying and re-marrying in the 1970s to 1980s but a relatively stable pattern in the 1990s to 2000–2002; and (6) a substantial decrease in the lifetime proportion of transition from cohabiting to marriage. We also present, for the first time, comparable evidence on differentials in union regimes between four racial groups.  相似文献   

19.
We examine recent fertility trends in Ethiopia for evidence of short- and long-term responses to famine, political events, and economic decline. We use retrospective data on children ever born from the 1990 National Family and Fertility Survey to estimate trends in annual marital conception probabilities, controlling for women's demographic and socioeconomic characteristics. The results of our analysis provide evidence of significant short-term declines in conception probabilities during years of famine and major political and economic upheaval. In the longer term, marital fertility in both urban and rural areas declined in the 1980s after increasing moderately in the 1970s.  相似文献   

20.
We use the PSID Relationship File to estimate cohort trends in the lifetime incidence and duration of female family headship. Hazard (event-history) techniques are used to estimate movements into and out of headship, accounting for duration dependence and left-censored spells. The mean number of years spent in headship between ages 14 and 59 rose dramatically over the period. The increase arose from an increased number of headship spells, including an increase in the number of women ever experiencing headship, but not at all from an increase in durations of headship spells; those decreased slightly.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号