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1.
Population projections depend on censuses, vital statistics and sample surveys, all of which have deficiencies that are most marked in the less developed countries (LDCs). Long-range projections by international agencies have recently undergone major revisions, while forecasts of the U.S. population have changed drastically over the past four years. The United Nations typically prepares “high,” “medium” and “low” projections. Even the high projection contains optimistic assumptions about fertility decline, while assumptions of constant or increasing fertility receive no serious attention. The paper suggests that high and constant fertility projections should receive more attention from policy makers, with medium estimates treated more as targets achievable only through considerable programmatic effort. At the same time, economic and social plans should be laid for dealing with the population sizes implied by the “high” variants.  相似文献   

2.
The United Nations publishes estimates of HIV prevalence, AIDS mortality, and orphan numbers for all countries of the world. It is important to assess the validity of these model-based estimates since they underpin much policy concerned with care and prevention. Household surveys that ask questions about the survival of children's parents (orphanhood) offer an independent source of data with which these estimates can be compared. Survey estimates of maternal and paternal orphans are significantly lower than model estimates for 40 surveys in 36 countries of sub-Saharan Africa (p < 0.001, p = 0.002). This is probably because adult mortality from causes other than AIDS is lower than assumed in the models, although under-reporting of orphanhood in surveys may also play a role. Reducing adult mortality from causes other than AIDS brings the model estimates into close agreement with the surveys. This suggests that the fraction of orphans attributable to AIDS is greater than estimated previously.  相似文献   

3.
This evolution over the last 50 years of data collection systems in less developed countries is assessed. The progress made by civil registration systems has been extremely disappointing. Except in Central and South America, their role in providing vital rate estimates is still very limited. In contrast, the promulgation of regular population censuses has been a success, particularly in Africa. The relative merits and demerits of different types of demographic surveys are described. To some extent multi-round designs have given way to single-round surveys, such as the Demographic and Health Surveys (DHS). DHS-style enquiries are particularly suitable for evaluation of interventions but are less appropriate if the main aim is to measure vital rates.  相似文献   

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Social scientists have increasingly used asset‐based wealth scores, like the Demographic and Health Survey (DHS) wealth index, to assess economic disparities. However, current indices primarily capture wealth in globalized market economies, thus ignoring other forms of prosperity, such as success in agricultural activities. Using a simple extension to the standard estimation of the DHS wealth index, we describe procedures for estimating an agricultural wealth index (AWI) that complements market‐based wealth indices by capturing household success in agricultural activities. We apply this procedure to household data from 129 DHS surveys from over 40 countries with sufficient land and livestock data to estimate a reliable and consistent AWI. We assess the construct validity of the AWI using benchmarks of growth in both adults and children. This alternative measure of wealth provides new opportunities for understanding the causes and consequences of wealth inequality, and how success along different dimensions of wealth creates different social opportunities and constraints for health and well‐being.  相似文献   

7.
In this paper, we examine empirical evidence for a relation between infant and child mortality and fertility in Latin American countries from 1920 to 1990. We investigate the relation at several levels of aggregation and evaluate the extent to which evidence at one level is consistent with evidence at other levels. We first examine aggregate cross-country information over several decades, a type of data typically used in past research on the topic. We also examine yearly series of births, deaths, infant deaths, and socioeconomic indicators for selected countries to track the association between short-term fluctuations in fertility and infant mortality. Finally, we use micro-level data from the Demographic and Health Surveys (DHS) to assess the relation between fertility and child mortality from individual reproductive histories. The evidence we assemble from these different data sets is remarkably consistent and suggests small positive effects of infant mortality on fertility. These effects, however, may be too small to support the hypothesis that changes in child mortality are of more than modest importance in the process of fertility decline in Latin America in the late twentieth century.  相似文献   

8.
Botswana and Zimbabwe have been acclaimed as being on the vanguard of the demographic transition in sub-Saharan Africa. This paper examines the comparability of the CPS and the DHS data for each country and finds that part of the observed decline in aggregate fertility rates in both countries can be attributed to differences in sample composition. Women of the same cohort tend to be better educated in the second survey relative to the first. This fact explains part—but not all—of the observed fertility decline; for example, it appears to account for up to half the observed decline among women age 25–34 in 1984 in Zimbabwe.  相似文献   

9.
Part, but not all, of the observed decline in the number of children ever born reported in the 1984 CPS and the 1988 DHS in Botswana and Zimbabwe can be attributed to differences in sample composition: women in the 1988 survey appear to be better educated than women of the same cohort in the 1984 survey. Blanc and Rutstein argue that differences in education levels in the pairs of surveys are not significant. However, weighted Kolmogorov-Smimov statistics, a comparison of average years of schooling, and the proportions of women who complete primary school or attend secondary school all indicate that the differences are, in fact, significant. This is true in both Botswana and Zimbabwe. Blanc and Rutstein also claim that these differences do not account for any of the observed decline in fertility between the surveys of women age 15 to 49. Their methodology follows cohorts of women rather than age-groups and thus cannot possibly address this issue. Furthermore, to interpret their results, response error and respondent education must be uncorrelated: this is a key assumption which is violated by the data. We stand by our conclusions and argue for caution when aggregate statistics from the CPS and the DHS are used to make projections about the course of fertility and population growth in Botswana and Zimbabwe.  相似文献   

10.
This study summarizes patterns of educational differentials in wanted and unwanted fertility at different stages of the fertility transition. The data are from Demographic and Health Surveys in 57 less developed countries. As the transition proceeds, educational differentials in wanted fertility tend to decline and differentials in unwanted fertility tend to rise. An assessment of fertility patterns in developed and less developed countries with low fertility concludes that these differentials are likely to remain substantial when less developed countries reach the end of their transitions. This conclusion implies that the educational composition of the population remains a key predictor of overall fertility in late transitional countries and that low levels of schooling can be a cause of stalling fertility.  相似文献   

11.
This study summarizes patterns of educational differentials in wanted and unwanted fertility at different stages of the fertility transition. The data are from Demographic and Health Surveys in 57 less developed countries. As the transition proceeds, educational differentials in wanted fertility tend to decline and differentials in unwanted fertility tend to rise. An assessment of fertility patterns in developed and less developed countries with low fertility concludes that these differentials are likely to remain substantial when less developed countries reach the end of their transitions. This conclusion implies that the educational composition of the population remains a key predictor of overall fertility in late transitional countries and that low levels of schooling can be a cause of stalling fertility.  相似文献   

12.
The fertility of immigrants' children increasingly shapes the ethnic diversity of the population in Western Europe. However, few data are available on the fertility patterns of immigrants and their offspring. This article provides new fertility estimates of immigrants and immigrants' children by ethnic group in the United Kingdom that may provide better‐informed fertility assumptions for future population projection models. The impact of migration‐specific tempo effects on the period TFR of immigrants is analyzed. Among the results, intergenerational fertility transitions strongly contribute both to fertility convergence between ethnic groups and to fertility “assimilation” or “intergenerational adaptation” to the UK mainstream childbearing behavior. Ethnic fertility convergence, particularly marked for populations originating from high‐fertility countries, reflects in part decreasing fertility in sending countries and in part intergenerational adaptation to the UK mainstream. Higher educational enrollment of the daughters of immigrants may partly explain their relatively lower fertility.  相似文献   

13.
We explored the relation between fertility and the business cycle in Latin America. First, we used aggregate data on fertility rates and economic performance for 18 countries. We then studied these same associations in the transitions to first, second, and third births with DHS individual data for ten countries. The results show that in general, childbearing declined during economic downturns. The decline was mainly associated with increasing unemployment rather than slowdowns in the growth of gross domestic product, although there was a positive relationship between first-birth rates and growth. While periods of unemployment may be a good time to have children because opportunity costs are lower, in fact childbearing was reduced or postponed, especially among the most recent cohorts and among urban and more educated women. The finding is consistent with the contention that, during this particular period in Latin America, income effects were dominant.  相似文献   

14.

The estimation of the mortality of the “oldest old”; is subject to considerable random error, but important prior information exists that can be used to make the estimates more robust. Mixed estimation is a method of incorporating auxiliary information into the statistical estimation of linear models. We extend the method to cover general maximum likelihood estimation, and show that the mixed estimator can be represented approximately as a weighted average of the purely data based estimator and the auxiliary estimator. The methods can be applied to the analysis of the old‐age mortality via logistic and Poisson regression. A major advantage of the mixed estimator is the simplicity with which it can incorporate partial prior information. Moreover, no special software is needed in the fitting. We show how the targeting methods of Coale and Kisker can be represented as mixed estimation in a natural way that is more flexible than the original proposal. We also derive empirical estimates of the target information based on pooled data from several countries with high quality data. We consider the mortality of Finland at ages 80 +, study the reliability of the evidence of mortality crossover, and derive estimates of life expectancy at age 100.  相似文献   

15.
While estimates of unmet need continue to be an important measure of the extent of demand for contraception and family planning programs success in developing countries, there are various reservations about the validity of these estimates. For instance, the traditional formulation of the measurement has relied solely on information from women while inferences from the findings are often drawn for couples. As more survey data have become available for both men and women in a number of countries, there is increasing evidence suggesting that husbands' preferences are indeed important determinants of the reproductive behavior of couples. This paper developsan analytical framework for measuring unmet need for couples. The approach: (1) takes a fresh look at the classification of pregnant and amenorrheic women, and (2) incorporates the contraceptive use and fertility preferences of husband and wife in estimating the level of unmet need in six sub-Saharan African countries. Our findings shows that taking these factors into account results in a 50 to 66 percent reduction in the level of unmet need in these countries. The importance of husbands' variables in determining the level of unmet need is clearly evident when examined among fecund couples in which the wife is neither pregnant nor amenorrheic. The implications of these findings for family planning programs and research are discussed.  相似文献   

16.
Interviewing some 350,000 women in 42 developing countries and 20 developed countries representing nearly 40% of the world's population, the World Fertility Survey (WFS) is in a unique position to document the historic 1970s slowdown in global population growth. This Bulletin describes efforts begun in 1972 to ensure high quality, internationally comparable, accessible data, the data's importance for policymakers, planners and researchers, and major findings available by early 1982 from directly assisted WFS surveys in 29 developing countries and contraceptive use data from WFS-type surveys in 16 developed countries. Marital fertility has declined in all developing regions except Africa but still averages from 4.6 children/woman in Latin America to 6.7 in Africa, while preferred family size ranges from 3.0 children in Turkey to 8.9 in Senegal--far above the average 2.2-2.5 children/woman needed to end developing countries' population growth in the long run. However, women ages 15-19 prefer nearly 2 children fewer than the oldest women ages 45-49; 3.8 vs. 5.7 on the average. Nearly 1/2 (48%) of married women surveyed in 27 countreis said they wanted no more children. Preventing all unwanted births would reduce birth rates up to 15 births/1000 population in these countries. Overall, 32% of married, fecund women in developing countries are using contraception compared to an average 72% in 16 developed countries. Education, literacy, and more available family planning services increase contraceptive use. Age at marriage is rising in Asia, but this factor alone has little effect on fertility. Infant mortality is higher in many developing countries than previously thought. Breastfeeding is an important restraint on fertility in most developing countries but is declining among more educated, employed, and urban women which could raise fertility if not compensated for by gains in contraceptive use.  相似文献   

17.
Iran has experienced one of the most successful family planning programs in the developing world, with 64 percent decline in total fertility rate (TFR) between 1986 and 2000. This paper focuses on Iranians’ unique experience with implementation of a national family planning program. Recognition of sensitive moral and ethical aspects of population issues resulted in successful collaboration of technical experts and religious leaders. Involvement of local health workers, women health volunteers and rural midwives led to great community participation. Demographic and Health Survey (DHS) data in 2000 indicated a TFR of 2.0 births per women and 74 percent contraceptive use among married women. This case study will help policy makers and researchers in Moslem countries and other developing countries with high fertility rate to consider a successful family program as a realistic concept with positive impacts on nation’s health and human development.  相似文献   

18.
Is the world converging to a single demographic regime? Or are groups of countries following distinct paths through the process of demographic transition? The answers to these questions are pivotal to our understanding of the nature and mechanisms of population change. They are also key elements for deriving the assumptions that should underlie population projections. There has been considerable interest in global demographic convergence during the last decade, with most work drawing on statistical methods that are widely used in economics. This article takes a different approach to most of the existing literature, examining the fertility and mortality trajectories over time that various appropriately defned world regions have followed. The data suggest that five distinct regional histories can be traced in mortality, and three in fertility, and that global convergence has moved more rapidly and unambiguously in fertility than in mortality.  相似文献   

19.
This is a general introduction to how population projections are made and used for the consumers of this information. Population projections are computations of what future trends in fertility, mortality and migration of a population might be given set assumptions. They are not actual forecasts. Projections are used by planners in government and business for a clearer understanding of social changes. How to prepare projections, obtain base data, select starting and future levels of rates, variant series, and the mathematics involved are discussed. Assumptions must be carefully checked and chosen, since reliability of the projections depends on assumptions. There are 3 rules of thumb for reliability: 1) the shorter the projection period, the more reliable the projection; 2) the larger the geographic area being projected the more reliable the projection; 3) the lower the current fertility and the higher the current life expectancy, the lower the projection's margin of error. Major sources of data and projections on world, regional, national, subnational, and local areas and difficulties with data for developing countries are discussed. Available microcomputer programs for IBM PC compatible machines are listed and described briefly.  相似文献   

20.
Following steep falls in birth rates in Central and Eastern European countries during the economic and institutional restructuring of the early 1990s, governments made substantial efforts to stop or at least reduce the fertility decline. In Hungary, parents with three or more children could benefit from specific new policy measures: the flat-rate child-rearing support paid from the youngest child's third to eighth birthdays (signalling recognition of stay-at-home motherhood) and a redesigned and upgraded tax relief system. However, the success of these policy measures, if any, is difficult to detect in aggregate statistics. Analysing data from the Hungarian Generations and Gender Survey, we rely on event history methods to examine the policies’ effects on third birth risks, especially among different socio-economic groups. The results indicate that while the child-rearing support increased third birth risks among the least educated, the generous tax relief had a similar effect for parents with tertiary education.  相似文献   

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