The demographic premises of affirmative action

The premise of affirmative action in the Sixties was that it was a temporary intervention necessary to help blacks overcome the legacy of slavery and segregation. Three decades later, affirmative action encompasses many other groups and has spread to a wide variety of programs. The growth, diversity, and increasing prosperity of non-black affirmative action groups, however, raises questions about the future role of race and ethnic preferences.     

The demographic context of recent change in the structure of American households

This article examines recent changes in the structure of American households within the context of broad population changes. Decreases in married-couple households and increases in single-parent households are almost entirely due to the changing patterns of marriage, divorce, fertility, and child custody; headship rates for families have remained relatively stable. Increases in single-person and other nonfamily households are due to increases in the size of the unmarried, childless population and to the aging of this population. Increasing propensities to live alone or with nonrelatives were observed between 1970 and 1980, but these behavioral changes have abated during the early 1980s.     

Climate-induced cross-border migration and change in demographic structure

Population and Environment - As climate change threatens livelihoods in Bangladesh, migration to neighboring countries in South Asia may accelerate. We use multiple types of data to predict how...     

Applying demographic analysis in affirmative action disputes: An instructional case

This instructional case study illustrates applications of demographic concepts, data, and techniques in evaluating affirmative action goals for equalizing employment opportunity. Courts of law addressing employment discrimination disputes need an accurate picture of each minority group's proportion in a pool of prospective employees. The demographic and socioeconomic factors conditioning those proportions vary from place to place. In the situation examined here, the court originally used an imperfect population standard to set hiring goals. The case traces the multiple failures to account for those conditioning influences and describes the resulting distortions of legal purpose. In analyzing this failure, students gain experience in clarifying issues in dispute, devising measures to fit legal standards, and delineating qualified labor pools. Specific instructional applications include: using census data to document how local population structure and composition determine each minority group's presence in the workforce; and using administrative data to delineate the relevant labor pools for setting affirmative action goals. Training is broadly suited to assignments where applied demographers must delineate the ethnic and racial composition of a pool of workers eligible to be hired or promoted.     

The development and use of demographic models

In this review, we first examine two classical demographic models - conventional life tables and stable populations - and a modern generalization of stable population theory; we then discuss mathematical models of conception and birth. These models involve purely mathematical relations in formal demography as opposed to empirical regularities. Next we consider model age schedules of mortality, nuptialitiy, marital fertility, fertility, and migration that are explicitly based on such empirical patterns. We close this empirical section with a discussion of model stable populations, which are based on model life tables. We next examine the use of demographic models in forecasting future mortality, nuptiality, and fertility and in population projection. Following a discussion of microsimulation models, which gives us the opportunity to mention model age schedules of post partum amenorrhoea and of sterility, we close with observations about the purposes and uses of demographic models.     

The demographic effects of a contraceptive programme

Abstract The calculation of the number of births prevented for each item of contraceptive service provided entails the integration of a variety of factors relating to the potential fertility of users and the duration and effectiveness of use. This article differs from previous essays of this kind in that estimates of future potential fertility are based not on fertility rates but on age-specific means of inter-live birth intervals, modified by periods of use overlapping post-partum sterility, and by the probabilities attached to the development of permanent sterility and to the successful adoption of extra-programme birth control. In the first three years after acceptance of intra-uterine contraception by some 9,000 postpartum women of several ethnic origins in Singapore, it is calculated that about 4,800 births were prevented.     

The exponential multidimensional demographic projection model

"This paper presents the multidimensional demographic projection on the basis of an exponential specification, which avoids the problems associated with the widely used specification on the basis of the linear integration hypothesis. It generalizes earlier work by Gill (1986) on Markov models for closed populations to include the case of open populations. A numerical illustration is also provided." (SUMMARY IN FRE)     

The exponential multidimensional demographic projection model

This paper presents the multidimensional demographic projection on the basis of an exponential specification, which avoids the problems associated with the widely used specification on the basis of the linear integration hypothesis. It generalizes earlier work by Gill (1986) on Markov models for closed populations to include the case of open populations. A numerical illustration is also provided.     

The analysis of linkages in demographic theory

Many seemingly different questions that arise in the analysis of population change can be phrased as the same technical question: How, within a given demographic model, would variable y change if the age- or time-specific function f were to change arbitrarily in shape and intensity? At present demography lacks the machinery to answer this question in analytical and general form. This paper suggests a method based on modern functional calculus for deriving closed-form expressions for the sensitivity of demographic variables to changes in input functions or schedules. It uses this “linkage method” to obtain closed-form expressions for the response of the intrinsic growth rate, birth rate, and age composition of a stable population to arbitrary marginal changes in its age patterns of fertility and mortality. It uses it also to obtain expressions for the transient response of the age composition of a nonstable population to time-varying changes in the birth sequence, and to age-specific fertility and mortality patterns that change over time. The problem of “bias” in period vital rates is also looked at.     

The cocos-keeling islands: A demographic laboratory

The Cocos Islands, which are situated in the Indian Ocean approximately halfway between Colombo and Fremantle, were first peopled early in the nineteenth century and were gradually developed as a very isolated coconut plantation with a labour force consisting partly of persons of Malay stock descended from the original group of settlers and partly of Bantamese contract labourers from Java. As the Cocos-born population increased in size, the dependence on contract labour decreased and, before the end of the century, all immigration ceased. The 1947 Malay population of the islands was about 1,800.

The islands are fascinating from a demographer's point of view because there was a virtually complete registration of live births, deaths and marriages and a partial registration of stillbirths. With these registration records it was possible to construct the life history of every individual from birth, through infancy and childhood to marriage, and thence through fatherhood or motherhood to death.

The picture revealed by an analysis of these records is that of a population with very high fertility and with mortality at a high level before the first World war and at a medium level after that war. Crude birth rates varied between 50 and 60 per thousand population during the period 1888 to 1947. Crude death rates were between 30 and 40 per thousand population until 1912 but under 2.0 per thousand population after 1918.

Most Cocos girls married before reaching the age of 20 and there were an average of between eight and nine live births per woman living through the childbearing period. There was a steady decline in the average number of live births with advancing age at marriage from age 16 onwards. A significantly high proportion of those dying in the middle of the childbearing period had never married, but the fertility of those marrying at an early age (14, 15 and 16) and dying before reaching the age of 36 was slightly higher than that of those who married at a similar age and survived. Women who survived to the age of 55 were of higher fertility than those who died between the ages of 40 and 55. An analysis of birth intervals revealed significant differences (a) between birth intervals after a stillbirth or after a live birth in which the child died in early infancy, and birth intervals after a live birth in which the offspring survived for longer than 0.4 years, and (b) between the interval from first to second birth and the subsequent birth intervals. There was a difference of almost exactly a year between the average birth interval after a stillbirth or live birth ending in a neo-natal death and the average birth interval after the birth of a child surviving to age 2; there was a similar difference of a year between corresponding median birth intervals.

From 1888 to 1912 infant mortality was well above 300 per thousand. After 1918 infant mortality averaged rather under 100 infant deaths per 1,000 live births. The reduction in infant mortality rates was accompanied by an increase in the mortality of children aged 1 to 4, and the heavy incidence of mortality at these ages after 1918 is the most striking feature of the analysis of mortality by age. Whilst mortality in infancy fell much more heavily on males than on females, early childhood mortality was much higher in Cocos for girls than for boys. The life table computed for the period 1918 to 1947 indicated a life expectancy of about 50 years for males and 47 years for females.     

Macroeconomic conditions, institutional factors and demographic structure: What causes welfare caseloads?

Some of the possible determinants of changes observed in welfare caseloads are analysed in this study. The paper attempts to explain variations in welfare caseloads on the basis of four different factors: macroeconomic conditions, interactions with other income maintenance programmes, changes in the programme's parameters and changes in the demographic structure. Different models are tested by applying time series techniques. The data employed are of an administrative nature and cover the whole period that the Madrid programme has been in operation. The results show that the effects of both unemployment and institutional variables are strong and significant. Macroeconomic effects on caseloads could be offset or reinforced by changes in unemployment protection and reforms of the programme's parameters. The significant effects found for the share of lone-parent applicants also show that demographic shifts could shape the trends of welfare rolls regardless of the changes in unemployment or the implementation of institutional reforms. The authors would like to thank Juan Gabriel Rodríguez, Minoru Kunizaki, Miguel Angel Malo and three anonymous referees for their comments and suggestions. Financial and technical support from the Spanish Institute for Fiscal Studies, the Inter-ministerial Commission on Science and Technology (SEC 2001-0746) and the Social Services Department of the Madrid Government is also gratefully acknowledged. Responsible editor: Christian Dustmann.