On the maximal life span of humans

"Mortality data from the Netherlands are analyzed using recently developed statistical methods in the field of extreme value theory. It is shown that there is a finite age limit. A 95% confidence interval for the age limit is 113-124 years. The results suggest differences between men and women. The suggested hypotheses could be tested on a larger data set." (SUMMARY IN FRE)     

Facing up to uncertain life expectancy: The longevity fan charts

This article uses longevity fan charts to represent the uncertainty in projections of future life expectancy. These fan charts are based on a mortality model calibrated on mortality data for English and Welsh males. The fan charts indicate strong upward sloping trends in future life expectancy. Their widths indicate the extent of uncertainty in these projections, and this uncertainty increases as the forecast horizon lengthens. Allowing for uncertainty in the parameter values of the model adds further to uncertainty in life expectancy projections. The article also illustrates how longevity fan charts can be used to stress-test longevity outcomes.     

Biological and social determinants of body size across the life span

The accuracy of demographic models designed to project future trends of population-level health and disease can be improved by incorporating biological data. One barrier to this process are quantitative characteristics of the data themselves. Biological data are characteristically time-dependent phenomena that behave in a nonlinear fashion. To develop accurate projections of the morbidity, disability, and mortality experience among future cohorts in late life, research needs to focus on development of models that create the opportunity to distinguish all-or-none, boundaries, and latency aspects of biological factors driving demographic phenomena, development of methods to identify time-dependent effects, and development of genetically informative samples. This presentation focuses on the biology of adult body size, its behavior as a variable in statistical analyses, and strategies for the incorporation of this variable into demographic models of population aging in the United States. First, several examples of generally observed quantitative characteristics of biological variables are reviewed. To illustrate the nonlinear character of biological data, three general patterns of change with aging are presented. Next, issues concerning the measurement of body size are discussed. Scenarios describing body size over the adult life span are described. By the end of this process, recommendations for starting a dialogue between researchers interested in biological endpoints (individual weight change, disease risk) and those interested in demographic outcomes (population-level disease and disability issues) using body size will be presented.     

Aging in America: Limits to life span and elderly care options

Expanding longevity among the elderly and fertility decline are contributing to an aging US population. The number of persons 65 years or older is projected to double from about 32 million in 1990 to 66 million by 2030; the elderly proportion is expected to increase from 13 to 22 percent over the same period. Chronic illness and functional disability afflicts a significant proportion of older persons. An estimated 80–85 percent of people over age 65 have at least one chronic illness, and nearly one-half of older people report that chronic illness limits their activity to some degree. Altogether, about one-third of the population over 65 may need some kind of medical or social assistance. This paper discusses the three primary modes of care available to older persons: (1) the informal network of the family, (2) the more formal arrangements of home and community care, and (3) the institutionalized care of nursing homes. Of particular policy interest are the questions: Who provides the care? What type of care is available? Who receives the care? How much does each type of care cost? and Who pays? The current patterns and costs especially of long-term care provide a framework for planning future options. A discussion of research and policy recommendations concludes the paper.     

The individual cost of sick leave

This paper aims to estimate the causal effect of sick leave on subsequent earnings and employment, using an administrative dataset for Norway. To obtain experiment-like variation in sick leave among otherwise similar workers, the leniency of these workers’ physicians—certifying sickness absences—is used as an instrumental variable for sick leave. A 1 percentage point increase in a worker’s sick leave rate is found to reduce his earnings by 1.2% 2?years later. Around half of the reduction in earnings can be explained by a reduction of 0.5 percentage points in the probability of being employed.     

The value and cost of children

Recent research on actual and perceived benefits and costs of children to their parents in both developed and less developed countries is summarized. Such figures and research cannot only help predict fertility behavior but can also provide data for welfare departments figuring support costs, courts setting support costs, and government planners allocating resources. Findings on costs and satisfactions from several major surveys are presented and then actual costs in the U.S. are presented in a series of tables. Research indicates that efforts to popularize small families could well take an economic approach - developing social security systems for the aged, substituting mother's for children's work in developing countries. Compulsory education might also help. 1 researcher suggests publicizing exact costs of raising a child. A survey in Hawaii found that parents uniformly underestimated the direct costs of each child. Also, couples might be most receptive to family planning during the years when economic costs are highest.     

The uncertain lifetime and the timing of human capital investment

I examine the effects of mortality decline on fertility and human capital investment decision of parents taking into account the uncertainty about child survival. I propose a model, where parents decide on their fertility before the uncertainty is realized, but they choose to invest only in human capital of their surviving children. The model implies a positive relationship between mortality and fertility and a negative one between mortality and educational investment. It has been argued elsewhere that as, in reality, most of the mortality decline occurred in infancy, it should not affect the human capital investment decision, which comes later in life. Thus, increased survival chances should not promote growth by raising the human capital investment. This paper argues the contrary and proposes a mechanism where mortality decline at any age before the teen years can promote growth by raising human capital investment regardless of the timing of the educational investment.      

The real cost of growth in Oregon

The costs of growth are little known, poorly understood and typically understated. This study is an initial effort to provide a more complete understanding of the current costs of growth in Oregon. While more than two dozen cost areas are identified, the focus is on basic physical infrastructure required for urban development. A proportionate share costing method is used to determine the public infrastructure costs associated with the construction of a typical single-family house. Each increment of growth is allocated costs for only the increment of system capacity required to serve it. Cost figures are from representative projects recently completed or underway in Oregon. The result is a composite of recent cost data selected to be representative of the state as a whole. An analysis of seven public infrastructure cost areas associated with the construction of a typical single-family house—including public facilities for schools, sewer, storm drainage, roads, water service, parks and recreation, and fire protection—shows that the total cost is about $24,500 per house. Oregon's development impact fees are recovering only a fraction of these costs. As a result, most of these public infrastructure costs are distributed across the entire population of a community through property taxes or general obligation bonds, whereas the benefits of these investments accrue primarily to the new development. The methodology used in this study can be easily replicated and may provide a useful tool for communities trying to obtain better information about the economic and fiscal impacts of urban growth. A review of relevant literature and references are provided.     

The cost of children. Part I

Using pre-war surveys of expenditure an attempt is made to assess the effect of the addition of one or more children on the distribution of expenditure. It is found that the changes between broad groups are small. The chief effect is an increased expenditure in the larger families on food and children's clothing, compensated by reduced expenditure on luxuries and adult clothing. It is confirmed that expenditure on accommodation does not rise with family size.     

The facts of life1

Two years before the appearance of Darlington's book, Louis I. Dublin published a volume with the same title. His Facts of Life were—sit venia verbi—“factual facts” from the number of people in the world to the dollar cost of World War II.     

The length of working life

The rapid growth of the aged population in recent years has underscored the economic problems of dependency in old age and has focused attention on the length of working life as compared to the total life span. In addition to interest in the average work-life span, students of labour-force dynamics have found a need for related measures of withdrawals from the labour force at different ages. In this paper, the author adopts the technique of the life table to a measurement of the work-life span by the construction of a table of working life.

Significant contrast is shown between total life expectancy and working life expectancy. In the United States, the average male worker at 20, for example, could expect to live for an additional 46.8 years and to remain in the labour force for an additional 41.1 years. He would therefore have to provide for almost 6 years of retirement. Significant differences are also indicated in comparisons by colour and residence. Further areas of study in applying the concept of working life are suggested.     

The cost of children. Parts II and III

In this paper the author estimates the compensating variation of income which will be necessary to keep the standard of living of a family constant when a child is born to the family. Various methods of estimation are tried, and an attempt is made to calculate the cost of a child in 1948, after allowances have been made for services provided by the government.     

The quality of life in Australia

This paper outlines a long term project on the quality of life in Australia and presents some initial survey data. The long term project is intended (1) to find which domains of life most affect the perceived well-being of Australians and the values/satisfactions people wish to achieve in these domains (2) to propose policy programs designed to enhance satisfaction with particular domains and (3) to assess the political feasibility of proposed programs. Policy programs intended to enhance satisfaction are termed positive welfare programs to distinguish them from conventional compensatory welfare programs. The survey data analysed here (national sample, N=679) deal with the satisfactions and dissatisfactions of Australians, the correlates of perceived well-being and the links between domains and values. Perceived well-being is measured by Andrews and Withey's Life-as-a-whole index and Bradburn's Affect Balance scale. Satisfactions are measured on a 9 point modified version of Andrews and Withey's delighted-terrible scale. Readers familiar with American, British and Canadian findings will find the results reported here broadly similar. However, the linkage between people's sociological characteristics and their satisfaction levels appears to be exceptionally weak in Australia, which tends to confirm the view that Australia is a comparatively unstratified society.     

The marginal cost of public funds with an aging population

"As populations in the United States and other advanced economies grow older, the burden of social security and health care financing is expected to rise markedly. Payroll, income, and other taxes on working populations are projected to rise accordingly. The marginal welfare cost to workers of social security and other public expenditures is analyzed within the context of a two-period life cycle model. By relaxing separability assumptions that have become common in the literature, the theoretical structure properly incorporates the effect of these public expenditures on labor supply. Comparative statics results indicate that changing age structure is likely to raise the marginal welfare to workers of social security, education, and other public expenditures. Illustrative calculations for the United States confirm this result, suggesting that the cost to workers of incremental social security benefits may easily double by 2025-2050."     

Optimal population control with uncertain output

"This note has shown how the techniques of stochastic control theory can be used to analyze the impact of uncertainty about non-labour inputs on optimal population control expenditure. While we have chosen very simple structure, it has allowed us to isolate the channels through which uncertainty affects the optimal plan, in this case causing expected expenditure on control to rise more slowly or fall more rapidly than its deterministic counterpart. Given the long-term implications of changes in population growth at any instant, and the stochastic nature of the environment in which control decisions are made, it is likely that useful insights could be obtained by extending the stochastic control approach to more complicated population control structures."     

Predicting overall life satisfaction: The role of life cycle and social psychological antecedents

Assessments of subjective well-being have been guided by a diversity of assumptions about overall life satisfaction's antecedents. Need hierarchy, affect, discrepancies between aspiration and attainment, and feelings of personal efficacy have all been suggested to be important predictors of satisfaction. But social psychological antecedents of satisfaction, such as indices of alienation, have heretofore not been considered, despite their link to the sociological tradition. These analyses suggest that for 1423 rural Wisconsinites, feelings of alienation are important predictors of overall life satisfaction. However, the impact of each of the two dimensions of alienation considered here varies with the respondent's position in the life cycle. Implications of these findings for research on life satisfaction are noted.     

The multistate life table with duration-dependence

"A method for generalizing the multistate, or increment-decrement, life table to include rates which depend upon duration of exposure to risk, as well as upon age, is proposed. The method is built upon the linear approximation, called the linear integration hypothesis, developed mainly by Rogers and his colleagues....It is possible to derive several new summary indices of the life-table cohort's history, such as the mean and median time in current status, at any age. The method is illustrated using a simple four-state marital-status model which has appeared often in the literature; here, rates of divorce and widowhood vary by duration of marriage as well as age." An example is demonstrated using 1984 period data for women in Finland aged 15-50. (SUMMARY IN FRE)     

The four-parameter logit life table system

Summary Brass's model life table system, which is a two parameter system based on the logit transformation of survivorship values, has been widely and successfully used to describe age patterns of mortality in many populations. As more reliable information has become available for populations with mortality patterns which differ in important ways from the assumed standard pattern of mortality, a more flexible model system is needed. This paper shows how Brass's system can be expanded into a four-parameter model, and evaluates the performance of the new system by examining how well it can fit observed life table data.     

Fertility in China: An uncertain future

As one of the world’s two population ‘billionaires’, the future of China’s population is truly of global significance. With its very low fertility and a rapidly ageing population, it might appear that the country’s famous (or notorious) family planning restrictions are somewhat anachronistic. Here, we explore the process of reform seen over the past three decades and, most recently, in late 2013. We suggest that the popular notion that the family planning restrictions are acting as a pressure valve suppressing a pent-up demand for childbearing, particularly in rural China, is likely to be inaccurate. We also suggest that further reform of the restrictions will not solve the problems of population ageing or many of the other issues widely associated with the restrictions. We conclude that the prospects for further reform are wide-ranging, but likely to be beset by many challenges.     

The stability and validity of quality of life measures

Effective social indicators must be stable when individual or societal characteristics are unchanged and dynamic when circumstances alter. Highly reliable measures may be poor indicators because they are insensitive to change. Little evidence is available on the sensitivity or validity of objective and subjective indicators. A lack of panel data has restricted the assessment of the stability of subjective measures. This paper examines longitudinal data on a representative sample of 2162 Canadians interviewed in 1977 and again in 1979. Test-retest correlations of approximately 0.50 were obtained for satisfaction and self-anchoring ladder measures among respondents who reported no significant changes in their lives during the past two years. Correlations were substantially lower, as expected, for those reporting life changes. Comparisons of the absolute values of these subjective indicators show that very little change in quality of life measures occurs when stable circumstances are reported but the indicators rise or fall significantly when situations change with downward adjustments being more dramatic than upward modifications. Positive and negative life events had little effect on overall evaluations of life quality. In general, these findings provide very strong evidence for the stability and validity of subjective indicators over time. These measures, with one exception, were constant in unchanging situations and sensitive to change when it occurred.