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891.
Parke R  Grymes RO 《Demography》1967,4(2):442-452
This paper reviews the methods used to prepare the new household projections for the United States that were recently issued by the Bureau of the Census and examines the effect on the resulting number of households of the assumptions made about future marriages and future proportions of household heads in the population.One population projection series was used, since all series are identical for the adult population. Marriage assumptions were generated by assuming various outcomes of the marriage squeeze (defined as the excess of females relative to the number of males in the main ages at marriage in the next few years). Assumptions about proportions of household heads were generated by assuming, in varying degrees, continuation of recent trends in these proportions.Projected changes in marriage and in the proportions of household heads in the population account for one-fourth to one-third of the projected increase in the number of households; the remaining increase is attributable to projected changes in the size and structure of the adult population. Varying the assumed proportions of household heads produces greater differences in the projected total number of households than does varying the marriage assumptions used here. Nevertheless, the various possible outcomes of the marriage squeeze, as represented by the assumptions used, produce significantly different projections of increases in the number of young husband-wife households.The most striking finding is that by 1985, proportions of household heads among the population not "married, spouse present" may well rise to such a level that over the long term, the smaller the number of persons who marry, the larger will be the number of households.  相似文献   
892.
Avery M. Guest 《Demography》1981,18(4):465-486
This paper investigates the importance of agricultural land shortages versus modernization of the society in influencing inter-state differentials in fertility in 1900, when the United States was in midtransition. Urbanization and manufacturing characteristics of states were the strongest correlates of variations in the index of total fertility because urban-industrialism depressed both the probability of marriage and marital fertility. Other modern characteristics of American states were also important in understanding variations in marital fertility. Low labor force employment of children and farm mechanization, integrally related characteristics, seemed to depress levels of marital fertility in many parts of the United States, independent of the urban-industrial system. Agricultural land opportunity had little overall effect on marital fertility; however, it was quite important in understanding variations in patterns of marriage.  相似文献   
893.
Saito O 《Population studies》1996,50(3):537-553
Historical demography as a separate discipline came into existence when family reconstruction was first developed for the analysis of a pre-transition population. This paper assesses the significant achievements made in this field of population studies since then. Attention is also paid to equally significant findings obtained from aggregative analysis based on back projection, and to a large body of research results for the period of the demographic transition. In the last part of the paper, new research directions are discussed. Data issues as well as methodological ones are raised. Special attention is given to newly emerging Asian historical demography where different source materials require different methods and techniques, which in turn are expected to broaden the scope of the so far disproportionality fertility-oriented field. Finally, discussions are extended to economic, cultural and institutional aspects of the subject, with a plea not to isolate demographic analysis from other branches of historical research.  相似文献   
894.
Avery M. Guest 《Demography》1979,16(3):401-415
Population redistribution within U.S. suburban rings between 1970 and 1975 was characterized by frequent population declines for individual suburbs. On the whole, recent spatial patterns of suburban population decline are similar in nature, if not overall levels, to those found in the 1950s and 1960s. Population decline is greatest in the inner suburbs, and is also evident, to some extent, in the most peripheral suburbs. Patterns for all metropolitan areas mask clear variation among metropolitan areas. This variation is related to metropolitan age or historical period of development.  相似文献   
895.
Abstract Although Buddist doctrine and institutions do not directly encourage the procreation of children, the Buddhist countries of South Asia (for the purposes of this paper, Ceylon, Burma, Thailand and Cambodia) have high fertility rates. The first half of this paper is devoted to examining possible reasons for this: particularly, whether there are non-Buddhist factors which produce high fertility and outweigh the negative Buddhist attitude, or whether there are less obvious factors within the structure of Buddhist culture which tend to produce high fertility indirectly; this preliminary review of evidence favours the latter explanation. In the second half of the paper South Asian Buddhist attitudes to policies of population control are examined. While in theory there is no Buddhist opposition to family planning, apart from the general Buddhist rejection of abortion, some differences of attitude towards other methods are observable between Ceylon and Thailand, the Buddhist opposition to contraception being stronger in the former than in the latter. It is suggested that the differences in attitude may be due to the larger proportion of non-Buddhists in the population of Ceylon than in Thailand, although the opposition is expressed in primarily doctrinal terms.  相似文献   
896.
In typical comparisons of inequality the condition that the means of the distributions are equal is hardly met. In these cases, the widely used Lorenz curves non-intersection criterion is neither a necessary nor sufficient condition for stochastic dominance. It is suggested to replace the Lorenz curves non-intersection criterion with an absolute Lorenz curves non-intersection criterion. The implications of adopting this criterion are discussed in the context of fixed populations and changing populations.This is a revised version of Harvard University Migration and Development Program, Discussion Paper No. 29. We are indebted to Pierre Pestieau for helpful comments and suggestions.  相似文献   
897.
898.
Probabilistic population forecasts offer a number of advantages to users. However, in some cases population is one component of a larger analysis that may take a different approach to uncertainty. For example, integrated assessments of environmental issues such as climate change or ecosystem degradation have typically used a small number of alternative scenarios to explore uncertainty in future environmental outcomes. In such cases, population projections that are provided only as probability distributions are difficult to use. I present a method of employing probabilistic population projections to derive individual, deterministic projections that can be used within scenarios for integrated assessments. The principal advantages of this approach are that (1) it provides a less ad hoc way of defining deterministic projections intended to be consistent with more comprehensive scenarios that describe, among other things, future socio-economic developments; (2) it provides more flexibility in specifying input assumptions for deterministic projections as compared to choosing off-the-shelf projections, allowing population assumptions to be tailored to the scenario; and (3) it provides a quantitative assessment of the uncertainty associated with any given deterministic projection. I describe the application of the method to the development of population projections used in integrated scenarios for the Millennium Ecosystem Assessment, an international scientific effort to assess the current conditions of and future outlook for global ecosystem goods and services. Results show that the MA scenarios are each consistent with a relatively wide range of demographic outcomes. For some scenarios, ranges of plausible outcomes in some regions overlap substantially, indicating that particular population projections could be consistent with more than one scenario. In other cases, uncertainty ranges for different scenarios are distinct, indicating that a projection consistent with one scenario is unlikely to be also consistent with another. Comparing variances of the conditional projections also provides insight into how much different storylines constrain future demographic developments. The development of the MA projections points to important areas of future research on correlations among demographic rates and on uncertainty across scales. It also serves as an illustration of how probabilistic and alternative scenario-based approaches to uncertainty can be combined within a single integrated analysis.This revised version was published online in April 2005 with corrections to figures 1-3.  相似文献   
899.
900.
The sequencing of marriage and first birth was expected to play an important role in the stability of marriage among adolescent mothers. We hypothesized that adolescent women who married prior to conception would have the lowest rates of marital disruption, followed by those who married between conception and birth. Adolescent women who gave birth prior to marriage were expected to suffer the highest rates of marital dissolution. The results provide partial support for our hypotheses. There is little difference in the probability of separation between adolescent mothers who had a postmarital conception and those who had a premarital conception but married before the birth. Having a premarital birth, however, significantly increases the probability of marital dissolution. We also hypothesized that marital status at first birth would have less effect on the probability of marital dissolution for blacks than for whites. This, too, is generally supported by our findings. Among black females, those with a premarital birth are the first to suffer a marital disruption, but by the end of ten years there is little difference in the probability of separation among the three marital status groups. In contrast, among white females, those with a premarital birth are the first to experience a disruption, and this differential persists over all subsequent marriage duration intervals. Thus, the sequencing of marriage relative to birth has similar short term effects for whites and blacks, but the effect for blacks is evident only in the short term. Ten years after the marriage, black adolescent mothers have similar rates of marital stability regardless of the sequencing of marriage. This is consistent with the findings of previous research and with our hypothesis; with the black family pattern of lower rates of marriage, higher rates of illegitimacy and higher divorce rates, the sequencing of marriage has no long lasting consequences on marital stability. Finally, our predicted decline in the effect of marital status at first birth over historical time also finds partial support. For white females there has been a change in the effect of marriage-first birth sequencing on separation over time. In the period encompassed by the women in our study, white adolescent mothers who married subsequent to the birth have been the most likely to experience a separation at all marriage duration intervals, but this differential narrows as age at interview declines. Among black females there has been no change in the effect of a premarital birth over time.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
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