Time series methods are used to make long-run forecasts, with confidence intervals, of age-specific mortality in the United States from 1990 to 2065. First, the logs of the age-specific death rates are modeled as a linear function of an unobserved period-specific intensity index, with parameters depending on age. This model is fit to the matrix of U.S. death rates, 1933 to 1987, using the singular value decomposition (SVD) method; it accounts for almost all the variance over time in age-specific death rates as a group. Whereas e 0 has risen at a decreasing rate over the century and has decreasing variability, k(t) declines at a roughly constant rate and has roughly constant variability, facilitating forecasting. k(t), which indexes the intensity of mortality, is next modeled as a time series (specifically, a random walk with drift) and forecast. The method performs very well on within-sample forecasts, and the forecasts are insensitive to reductions in the length of the base period from 90 to 30 ...

https://pages.stern.nyu.edu/~dbackus/BCH/demography/LeeCarter_JASA_92.pdf

Modeling and forecasting U. S. mortality

The Analysis of Time Series: An Introduction, 4th edn. By C. Chatfield. ISBN 0 412 31820 2. Chapman and Hall, London, 1989. 242 pp. £13.50.

The Analysis of Time Series: An Introduction

Cet article se propose d’examiner d’une maniere critique les projections urbaines des Nations Unies. 
Les estimations des tendances recentes basees sur les donnees nationales sont evaluees, de meme que 
la methode de projection. La theorie de la transition urbaine est utilisee comme une alternative pour 
les projections. Des projections alternatives sont proposees sur la base d’un modele polynomial et sont 
comparees a celle des NU, qui sont fondees sur un modele lineaire. Les conclusions sont que les 
projections des NU pourraient surestimer de pres d’un milliard la population urbaine en 2030, soit 
19% en terme relatif. La surestimation serait particulierement plus prononcee pour les pays en 
developpement et pourrait exceder 30% en Afrique, en Inde et en Oceanie.

/pdf/world-urbanization-prospects-an-alternative-to-the-un-model-2szgzojfgy.pdf

World urbanization prospects: an alternative to the UN model of projection compatible with urban transition theory

This paper proposes to critically examine the United Nations projections on urbanisation. Both the estimates of current trends based on national data and the method of projection are evaluated. The theory of urban transition is used as an alternative hypothesis for projections. Alternative projections are proposed using a polynomial model and compared to the UN projections, which are based on a linear model. The conclusions are that UN projections may overestimate the urban population for the year 2030 by almost one billion, or 19% in relative term. The overestimation would be particularly more pronounced for developing countries and may exceed 30% in Africa, India and Oceania.

World urbanization prospects: an alternative to the un model of projection compatible with urban transition theory 1

We describe an approach for estimating occupancy rate or the proportion of area occupied when heterogeneity in detection probability exists as a result of variation in abundance of the organism under study. The key feature of such problems, which we exploit, is that variation in abundance induces variation in detection probability. Thus, heterogeneity in abundance can be modeled as heterogeneity in detection probability. Moreover, this linkage between heterogeneity in abundance and heterogeneity in detection probability allows one to exploit a heterogeneous detection probability model to estimate the underlying distribution of abundances. Therefore, our method allows estimation of abundance from repeated observations of the presence or absence of animals without having to uniquely mark individuals in the population.

Estimating abundance from repeated presence–absence data or point counts

Introduction to Multiregional Mathematical Demography

This report draws on the fundamental regularity exhibited by age profiles of migration all over the world to develop a system of hypothetical model schedules that an be used in multiregional population analyses carried out in countries that lack adequate migration data. (EXCERPT)

Model migration schedules

This paper was prepared for presentation at the 36th North American Meetings of the Regional Science Association November 10-12 1989 in Santa Barbara. This work was supported by National Science Foundation Grant No. SES-8705591. The author is grateful to Brian Cushing Tom Espenshade Gary Hunt Nathan Keyfitz Jacques Ledent Andrew Morrison and Peter Mueser for comments and to Debbie Ash and Carrie Andree for typing the manuscript. Throughout this paper I focus on analyses carried out using rates rather than counts of the absolute numbers of events even though some published studies of net migration have used the latter. (EXCERPT)

Requiem for the net migrant.

In this introduction of the interregional dimension into the emerging theory of mathematical demography, the vehicle is matrix algebra and the focus is upon a simultaneous consideration of the spatial and temporal aspects of population processes. The author draws on the notational and analytical advantages conferred by matrix algebra to develop insights that are obscured or unobtainable with conventional methods of analysis. He then considers several of the more interesting theoretical and practical questions to which his approach leads. $5.00

Matrix Analysis of Interregional Population Growth and Distribution

A number of recent cross-sectional studies of longevity and health among the elderly have concluded that recent positive trends in the prolongation of life have not been matched by similar trends in the extension of healthy life. This paper challenges that pessimistic conclusion by examining conceptual issues related to the measurement and dynamics of the mortality-disability process. It uses data from the 1986 Longitudinal Study of Aging (U.S. Department of Health and Human Services, 1988) to illustrate its principal points.

Andrei Rogers

Papers

Introduction to Multiregional Mathematical Demography

Model migration schedules

Requiem for the net migrant.

Matrix Analysis of Interregional Population Growth and Distribution

Longer Life but Worse Health? Measurement and Dynamics