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1.
This paper presents the results of an attempt to determine, through the use of demographic analysis, the approximate magnitude of the resident illegal alien population in the United States. The method described is the comparative analysis of trends in age-specific death rates in the United States and selected States, 1950 to 1975. The procedure depends on two assumptions: (a) that few or no illegal aliens are included in decennial census counts or current population estimates; and (b) that the reported statistics on deaths include deaths to all or nearly all illegal aliens. If the illegal alien population has increased by several million since 1970, then death rates in geographic areas where illegal aliens are most concentrated should show substantial excesses over the rates for the remainder of the country. A roughly similar downward trend in the death rates of all age groups since 1970 in all areas of the United States is apparent and hence does not support the view that many millions of illegal residents (perhaps over 6 million) are living here. However, the finding of a persistent deviation in the death rate trend for 10 selected States since 1960 for whites males, ages 20 to 44, and for no other group, suggests that the deaths of illegal aliens are being recorded in our vital statistics system. A range of estimates of the illegal alien population based on this analysis is presented and compared with the results of other studies.  相似文献   

2.
Keyfitz N 《Demography》1969,6(3):261-269
Some populations, like that of the United States in the 1950's, have a smaller proportion of women of reproductive age than they would ultimately attain with continuance of their age-specific birth and deaths rates, a continuance which produces the condition known in demography as stability. Others, like that of the United States in the 1930's, have relatively more women of reproductive age than they would ultimately attain with stability. A way of studying ages is to calculate how many women of stable age distribution would be equivalent from the viewpoint of reproduction to the women observed. This stable equivalent was 69,535,000 or 16 percent below the observed United States female population in 1955, and 12 percent above the observed in 1935. The stable equivalent is a measure of fertility potential, closely related to R. A. Fisher's reproductive value. Calculations for four countries illustrate how a fall of the birth rate, for example in demographic transition, occasions an age distribution in which the stable equivalent is greater than the observed number of women. The notion of stable equivalent is useful for comparison because changes in it are nearly invariant with respect to the age-pattern of fertility used. The statement that the United States stable equivalent increased by 11 percent between 1960 and 1965 holds irrespective of whether the 1960 or the 1965 age-specific fertility and mortality rates are used as standard.  相似文献   

3.
Chang HC 《Demography》1974,11(4):657-672
As a follow-up on the studies by Dorn and Beale, this paper examines differences between Iowa counties with natural decrease and those with natural increase and analyzes the part that migration and fertility played in bringing about an excess of deaths over births in Iowa counties. The county groups are distinctly different in demographic and socioeconomic characteristics. Out-migration as a mode of response adopted by the rural population in Iowa is by far the most dominant factor leading to natural decrease. Sustained net out-migration is more likely to touch off natural decrease in counties of comparatively low fertility than in those with higher fertility. Low fertility is, therefore, a contributing factor to the imbalance between births and deaths, but the amount of influence of fertility adjustment over the fertility differentials among county groups cannot be ascertained in this study because of the correlation between fertility and Catholic Church membership in counties. The data of this study were obtained from the population censuses and vital statistics.  相似文献   

4.
Abstract A complete and efficient registration system, of the type which would provide good data on births and deaths, does not exist in Ghana. However, registration of vital events is supposed to be compulsory in 39 towns in the country but the data collected in these areas are too inadequate and defective to provide a sound basis for the analysis of the dynamics of population growth. The results of the censuses conducted by the colonial governments are so defective and unreliable that they do not allow scientific research in the field of population analysis. Before 1960, therefore, when the national census and the post-enumeration survey (based on a 5% sample of the population) were carried out, estimates of fertility and mortality levels were little more than guesses. In this study an attempt has been made to utilize the information on the age-sex composition provided by the 1960 census and post-enumeration survey data on births and deaths to determine, as far as possible, the levels of fertility and mortality and the rates of population growth in Ghana. The fertility estimates-i.e. a crude birth rate of 50, total fertility rate of 6.9 and a gross reproduction rate of 3.4-show that Ghana's fertility is one of the highest in the world. An expectation of life at birth of 40 years, an infant mortality of 160 and a crude death rate of 23 appear to be the most plausible estimates. These estimates yield a rate of natural increase of 2.7% and a growth rate of 3.0% per annum.  相似文献   

5.
"In this paper, we consider crossovers of demographic density distributions from...populations that have the same fertility and mortality rates. We focus on observed populations and their associated stationary and stable models, and on proportional distributions of persons, births, deaths and reproductive values....Three different populations were selected to represent a range of demographic behavior. Those populations are Japan 1963, a low mortality, low fertility population; Togo 1961, a high mortality, high fertility population; and the United States 1919-1921, a population whose fertility and mortality are intermediate."  相似文献   

6.
J Pan 《人口研究》1984,(1):53-57
Most developing countries are in the demographic stage of early mortality, high birth rates and high rates of natural population increase. A characteristic of developing countries is that after World War ii, particularly since the 1960s fertility rates are on the decline, even though they still remain high. The fertility rate of developed countries fell from a 1950 rate of 22.9/1000 to 15/1000 in 1982, a decrease of 34.5%, whereas the fertility rate of developing countries hovered around 43/1000 between 1930-1950, 40.6/1000 during the 1960s and 33/1000 in 1982. Between 1950 and 1982 there was a decrease of 24.8%. But the main reason for this decrease is the decline in the last 20 years of the fertility rates of China and India, whose rates fell 34.9% from 1960-1980. Changes in fertility rates are influenced by the age structure of a country, as seen in the changing age structure of developing countries from 1960-80. For example, an increase in fertility rates was 1 consequence of an increase in the number of fertile women aged 15-45 from 42.6% in 1960 to 44.4% in 1980. Nevertheless, there exists some sort of birth control, whether conscious or subconscious, because the number of births per fertile woman is 3-4 fewer than the 14-15 children a woman can theoretically bear. The reason for changes in fertility rates in developing countries can be traced to marriage and family customs, and even more important, to social and economic factors. For example, Asian, African and Latin American cultures tend to support early marriages. When the fertility rates of developed and developing countries are looked at for a comparable period, then the rate of decrease for developing countries is slower than developed countries. But, if the comparison is made for a transitional period (i.e., industrialization), then the rate of decrease for developing countries is faster than for developed countries. Currently there are 25 developing countries that have attained a fertility rate of 25/1000 or lower, and 52 developing countries with a rate of 35/1000.  相似文献   

7.
Age at marriage and timing of the first birth   总被引:1,自引:0,他引:1  
Summary An attempt has been made to measure the effect of age at marriage of brides on the timing of the first birth. In Australian vital statistics, first nuptial confinements have been tabulated by age of mothers and by single years of marriage duration in single months for the first two years and by single years for all other durations since 1916. A simple technique has been used to link such data with marriage cohorts. The study briefly reviews the prevailing patterns of the timing of first births by mothers' age at marriage and changes in this pattern since the marriages of the 1925/9 period. The analysis shows that after a period of relative stability of family formation patterns in the 1950s and early 1960s, women married in the late 1960s started postponing the first birth beyond the first two years of marriage. It is suggested that a fraction of the decline in total births recorded in Australia since 1972 can be attributed to the postponement of first nuptial confinements by women married in the late 1960s and early 1970s.  相似文献   

8.
A major aim of this study is to address our lack of understanding of rural-urban population change within nonmetropolitan counties of the United States. Specifically, we (a) examine trends between 1950 and 1975 in differential rural and urban growth rates within nonmetropolitan counties, and (b) examine the relationship between county location/function and within-county deconcentration. We show that the post-1970period has not simply marked the net shift of population from metropolitan to nonmetropolitan areas, but has also ushered in a pattern of population deconcentration within most nonmetropolitan areas. It is also clear that traditional ecological and economic base variables have been of diminishing utility in explaining deconcentration during the 1970s, suggesting that deconcentration is now evident in nonmetropolitan counties characterized by a broad spectrum of economic and sociodemographic traits.  相似文献   

9.
It is well established that the timing of childbearing is transmitted from parents to children in the United States. However, little is known about how the intergenerational link has changed over time and under structural and ideological transformations associated with fertility behaviors. This study first considers changes across two birth cohorts from the National Longitudinal Survey of Youth (NLSY) in the extent to which parents’ age at first birth is transmitted to their children. The first cohort includes individuals born during the late 1950s through the early 1960s (NLSY79), while the second includes individuals born in the early 1980s (NLSY97). Results from discrete-time event history analyses indicate that the intergenerational transmission of age at first birth significantly increased for both daughters and sons. These results were confirmed by analyses of data from three cycles of the National Survey of Family Growth spanning the same time period. Over this period, age at first childbirth became increasingly younger for children born to teenage mothers and increasingly older for those born to mothers who began parenthood after age 25. These patterns have important implications for the reproductive polarization hypothesis.  相似文献   

10.
韩国人口老龄化过程及其启示   总被引:1,自引:0,他引:1  
金度完  郑真真 《人口学刊》2007,299(5):44-49
韩国人口老龄化的过程与中国有很多相似之处,经历了20世纪50年代的高生育率和死亡率降低、60年代以后的生育率下降直到目前的超低生育率,韩国人口在世纪之交快速进入老龄化阶段。预计初婚年龄的升高、持续的低生育率和育龄妇女数量的减少将会使韩国人口进一步老化。快速的人口老龄化已经为韩国社会带来了一系列的经济和社会问题,应对老龄化带来的挑战成为国家面临的重大问题。韩国的老龄化过程、现状以及采取相应的对策,将对中国具有启示意义。  相似文献   

11.
Existing knowledge of Tibetan historical population development is mostly based on ‘best-guess’ estimates and is heavily politicized. Using census data, I reconstruct the development of Tibetan fertility in China since the 1940s, with the objective of providing an independent assessment that can be used as benchmark for future studies and debates on Tibetan demography. Following major social and economic transformations starting in the 1950s, Tibetan fertility unexpectedly increased from the late 1950s to the late 1960s. As noted in several existing studies, Tibetan fertility in China then declined swiftly from the early 1980s onwards and has now reached values close to replacement level. Focusing on the 1950–70 period, I examine factors that contributed to shaping the Tibetan fertility increase in more detail. This confirms that changes in nuptiality and disease-related infertility both played a role in pushing up fertility rates among Tibetan women in China.  相似文献   

12.
This paper describes new midyear (July 1) estimates of the "true" population of the United States by age, sex, and color (white, nonwhite) for the 1940s and 1950s. It also presents the corresponding implied coverage estimates for the 1940 and 1950 censuses. The new population estimates are calculated by combining the most recent figures on the 1960 population with estimates of the demographic components of change for the 1950s and 1940s in an iterative reverse cohort-component projection algorithm. Among the principal findings of the new estimates are: (a) existing midyear estimates of the "true" population in the 1950s are 450,000 to 500,000 too high; (b) existing age-specific estimates for the 1950s tend to underestimate the population at the older ages (55 years and over) and overestimate the population in the young and middle adult years (15 to 54 years); (c) estimates of the "true" population in the 1940s were too low except for nonwhites at ages 65 and over; (d) existing estimates of percentage net undercount and underenumeration for the 1950 and 1940 censuses tend to be too high, substantially so for nonwhites in the 1940 Census; and (e) nonwhites were more completely enumerated in 1940 than in 1950. Thus, in addition to being methodologically and temporally consistent with post-1960 estimates, the new population estimates described here imply some substantial revisions in demographic, social, and economic statistics for the two decades prior to 1960.  相似文献   

13.
Since 1940, under conditions of restricted immigration and high and sustained growth in aggregate demand, shifts in the relative number of younger versus older adults have had a pervasive impact on American life. Before 1960, younger males were in increasingly short supply and their relative economic position substantially improved; after 1960, the opposite was true. Since the early sixties, as the relative condition of young adults has deteriorated, marriage has been increasingly deferred and fertility reduced. The labor force participation of young women has risen at above average rates, and that of older women has risen at below average rates. Changes in the age structure of the working age population have also contributed to a combination of rising unemployment and accelerating inflation. Cohort divorce rates, suicide among young males, crime rates, and political alienation have worsened. The rise in college enrollment rates has been interrupted, and SAT scores have declined. In contrast, in the period 1940–1960, changes in these various magnitudes were typically of a more favorable sort. The United States is now at the start of a new period of growing scarcity of young adults as a result of the birth rate decline that set in after 1960. This implies that the 1980s will see a turnaround or amelioration in a wide variety of these social, political, and economic conditions, some of which have been taken as symptomatic of a hardening social malaise.  相似文献   

14.
Spiegelman M 《Demography》1966,3(2):574-577
The plan calls for monographs on 16 specific topics and a review volume. The specific topics include a monograph on fertility, another on marriage and divorce, and one on social and economic factors in mortality, all of which are of obvious demographic interest. The core of the development of the monographs dealing with the disease topics, and accidents, homicide, and suicide, is a tabulation program involving specific and age-adjusted death rates based upon the deaths in the United States for the three year period 1959-61 and the 1960 census of population. The program called for a set of standard tabulations common to each monograph and also a set of special tabulations tailored to meet the particular needs for each topic as specified by its authors. This wealth of demographic detail regarding mortality in the United States during 1959-61 fills only one aspect of its health picture. To fill out the health picture, use is being made of the great volume of morbidity data out of the National Health Interview and Examination Surveys and a wide variety of other specialized surveys. In all of these, the findings are invariably described in terms of the demographic characteristics of age and sex, and frequently in terms of such social-economic variables as education, income, work status, and occupational class.A large part of the content of the monograph on social and economic factors in mortality will come out of available results of the 1960 census-death certificate matching study at the University of Chicago. One important feature of this monograph, not contained in the Chicago study, is a regression and correlation analysis of total mortality in 202 Standard Metropolitan Statistical Areas in relation to a large number of social, economic, and climatic factors. Among the features in the monograph on fertility are chapters on the medical and biological characteristics of births, fecundity and family planning, and an analysis of cohort fertility trends. The monograph on marriage and divorce will make use of the detailed tabulations from the 1960 census on marital status in relation to education, race, parentage, earnings and other classifications of individuals and of husband and wife in married couples. It will also contain a matching study of divorce records in certain states for a short period before the census of 1960 with the returns in the census. The project is supported by a grant from the United States Public Health Service (CH 00075; formerly RG 08262). Publication will be by the Harvard University Press.  相似文献   

15.
North and South Korea have both experienced demographic transition and fertility and mortality declines. The fertility declines came later in North Korea. In 1990, the population was 43.4 million in South Korea and 21.4 million in North Korea and the age and sex compositions were similar. This evolution of population structure occurred despite differences in political systems and fertility determinants. Differences were in the fertility rate and the rate of natural increase. The total fertility rate was 2.5 children in North Korea and 1.6 in South Korea. The rate of natural increase was 18.5 per 1000 in North Korea and 9.8 in South Korea. Until 1910, the Korean peninsula was in the traditional stage characterized by high fertility and mortality. The early transitional stage came during 1910-45 under the Japanese annexation. Health and medical facilities improved and the crude birth rate rose and then declined. With the exception of the war years, population expanded as a function of births, deaths, and international migration. Poor economic conditions in rural areas acted as a push factor for south-directed migration, migration to Japan, and urban migration. Next came the chaotic stage, during 1945-60. South Korean population expanded during this period of political unrest. Repatriation and refugee migration constituted a large proportion of the population increase. Although the war brought high mortality, new medicine and disease treatment reduced the mortality rate after the war. By 1955-60, the crude death rate was 16.1 per 1000 in South Korea. The crude birth rate remained high at 42 per 1000 between 1950-55. The postwar period was characterized by the baby boom and higher fertility than the pre-war period of 1925-45. Total fertility was 6.3 by 1955-60. The late transitional stage occurred during 1960-85 with reduced fertility and continued mortality decline. By 1980-85, total fertility was 2.3 in the closed population. The restabilization stage occurred during 1985-90, and fertility declined to 1.6. In North Korea, strong population control policies precipitated fertility decline. In South Korea, the determinants were contraception, rising marriage age, and increased use of abortion concomitant with improved socioeconomic conditions.  相似文献   

16.
Abstract The paper describes a computerized model developed to simulate the fertility of a hypothetical marriage cohort in a closed population. The model was applied to England and Wales fertility data of marriage cohorts of the years 1951 to 1970. For each of these cohorts, the computer was programmed to construct five series of tables showing birth-order probabilities, family size frequency distribution, mean length of intervals between marriage and successive births, parity progression ratios and mean family sizes of fertile women. The results showed that the fertility of the cohorts of women who married between the middle 1950s and the early 1960s was character ized by a declining trend in the frequency of childlessness and by a dramatic increase in the proportion of marriages with two or more children. Since 1964 or so, there has been a downward trend in duration-specific birth-order probabilities. The analysis suggests that the recent drop in fertility may well prove to be the effect of an upward shift in the timing of births as well as a fall in completed fertility.  相似文献   

17.
Hill A 《Population studies》1975,29(3):355-372
Summary Fertility indices of one sort or another can be calculated for the Asian populations of Uganda and Kenya back to 1931. These indices suggest that fertility has fallen sharply during the 1950s and 1960s. Considerable problems are experienced in trying to determine the actual level of fertility, however, since all the techniques developed to deal with defective data are so affected by the falling fertility and migratory movements of the population, as to be virtually useless. An analysis of the causes of the fertility decline suggests that both changes in marriage patterns and changes in fertility within marriage have contributed to the fall, and that these changes have come about as a result of the better education and economic opportunities available to the Asian community.  相似文献   

18.
R Zha  Y Ji 《人口研究》1984,(6):11-20
The 1982 census provided detailed information on fertility in China. It recorded 20,689,704 births in 1981, producing a birth rate of 2.1%, a decrease, respectively, of 43% and more than 50% in comparison with 1952 and 1963. The birth rate has varied widely over the last 30 years, from 3.6% in the early 1950's, to 1.8% in 1961, after a planned birth program was begun, to a record high of 3.7% in 1962 following the economic recovery, to 3.3% in 1970, after a gradual decline through the 1960's. By 1981 the birth rate had declined to 2.1%, clearly resulting from the intense planned fertility promotion begun in the early 1970's. In the mid- and late 50's, urban birth rate was consistently higher than rural, with the mass move to the cities at the beginning of the People's Republic. General economic development after 1957 brought simultaneous declines of both urban and rural rates, both reaching a low point in 1961. Age structure of the population also has an influence, depending on the proportion of childbearing women in the population. In 1981, the fertility of China's childbearing women was 8.3%, lower than that of the developing countries, but higher than the developed countries. By age group, the fertility rates reached 14.7% and 23.9% respectively in women between 20-24 and 25-29 years of age; the legal marriage age is 20. The fertility rate in large cities is generally lower than that of provinces. Higher educational and socio-economic level also exert an inverse influence on fertility rates; in low socio-economic areas the rate reached 3.5%, and in more advanced areas it was held to 2.2%. In all professions with the exception of agriculture, fishing, and forestry, the percentage of families with 1 child was 81.8%. Since planned fertility was implemented, the overall fertility rate has dropped from 3% to 2%. China's fertility mode has changed to that of developed countries, with high intensity between 20 and 29 years of age. Appropriate measures should be taken to lower the fertility rate in different regions.  相似文献   

19.
Y Wang 《人口研究》1985,(3):44-48
Using statistical data, this report analyzes population and economic issues in West Asia after World War II. The high rate of development as witnessed in West Asian countries after their gaining of political independence following World War II was accompained by an accelerated population growth. This population growth spead unevenly among different areas. Based on surveys of 17 countries in West Asia, the socioeconomic development and rapid rate of population growth have largely affected the population age, sex, urban and rural residential, and economic sector employment structures. With the help of indicators and mathematical methods to plot population development, these countries can be divided into 3 categories based on population development features. The semiindustrial countries demonstrate a gradually slowing population growth rate, most of these countries having experienced a peak period in the growth rate during the time of population transition. The agricultural countries show a natural population growth rate which is generally considered low. The 3rd category, the oil-producing countries, are currently experiencing a peak in population growth. In general, the popuation growth rate has dramatically accelerated in West Asia since World War II. Between 1950-1960 this rate was 2.58%; between 1960-1970, 2.75%; and between 1970-1980, 2.92%. This rate shows an increase of 6.6% between 1950-1960 and 6.2% between 1960-1970. It surpasses the average world population growth rate and most of the developing country growth rates. It has been augmented by post-World War II economic and social developments.  相似文献   

20.
Before the demographic transition in Thailand, fertility was high, but not uniformly so. As in other pre-transition settings, Thai fertility responded to pressures and opportunities created by socioeconomic structure and land availability. Drawing upon provincial data from the 1947 and 1960 censuses of Thailand, we find a strong 'frontier effect' on Thai fertility in the 1950s. Fertility was higher in sparsely settled frontier provinces and lower in provinces with higher population density relative to cultivatable land. This finding is robust and holds up with controls for agricultural employment, land quality, and the sex ratio (an indicator of sex-selective migration). The effect of population pressure lowers the likelihood of marriage and of marital fertility. The findings from Thailand are consistent with the research of Easterlin on the nineteenth century United States and with other pre-transition societies. We suggest how demographic transition theory might be broadened to include fertility dynamics in pre-transition societies.  相似文献   

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