Mathematical demography is the centerpiece of quantitative social science. The founding works of this field from Roman times to the late Twentieth Century are collected here, in a new edition of a classic work by David R. Smith and Nathan Keyfitz. Commentaries by Smith and Keyfitz have been brought up to date and extended by Kenneth Wachter and Herve Le Bras, giving a synoptic picture of the leading achievements in formal population studies. Like the original collection, this new edition constitutes an indispensable source for students and scientists alike, and illustrates the deep roots and continuing vitality of mathematical demography.

The book that follows is an experiment in the teaching of population theory and analysis. A sequence of problems where each is a self-contained puzzle, and the successful solution of each which puts the student in a position to tackle the next, is a means of securing the active participation of the learner and so the mastery of a technical subject. How far our questions are the exciting puzzles at which we aimed, and how far the sequence constitutes a rounded course in demography, must be left to the user to judge. One test of a good problem is whether a solution, that may take hours of cogitation, is immediately recognizable once it comes to mind. While algebraic manipulation is required throughout, we have tried to emphasize problems in which there is some substantive point-a conclusion regarding population that can be put into words. Our title, Demography Through Problems, reflects our intention of leading the reader who will actively commit him-or herself through a sequence that will not only teach definitions-in itself a trivial matter-but sharpen intuition on the way that populations behave.

The third edition of this classic text maintains its focus on applications of demographic models, while extending its scope to matrix models for stage-classified populations. The authors first introduce the life table to describe age-specific mortality, and then use it to develop theory for stable populations and the rate of population increase. This theory is then revisited in the context of matrix models, for stage-classified as well as age-classified populations. Reproductive value and the stable equivalent population are introduced in both contexts, and Markov chain methods are presented to describe the movement of individuals through the life cycle. Applications of mathematical demography to population projection and forecasting, kinship, microdemography, heterogeneity, and multi-state models are considered.

The new edition maintains and extends the book's focus on the consequences of changes in the vital rates. Methods are presented for calculating the sensitivity and elasticity of population growth rate, life expectancy, stable stage distribution, and reproductive value, and for applying those results in comparative studies.

Stage-classified models are important in both human demography and population ecology, and this edition features examples from both human and non-human populations. In short, this third edition enlarges considerably the scope and power of demography. It will be an essential resource for students and researchers in demography and in animal and plant population ecology.

From the reviews:

"If you found the original editions...to be excellent (and who amoung us has not?) then you will find the new edition to be equally so...This book is highly andunreservedly recommended for any beginning mathematical demographer." Mathematical Population Studies, 12: 223-228, 2005

"The material in the second edition is retained, although the chapters are reorganized and references are updated. New chapters focusing on matrix population models are seamlessly interwoven with the second edition chapters, resulting in a thorough and comprehensive treatment of human, animal, and nonhuman demography." Journal of the American Statistical Association, December 2005

Mathematical demography is the centerpiece of quantitative social science. The founding works of this field from Roman times to the late Twentieth Century are collected here, in a new edition of a classic work by David R. Smith and Nathan Keyfitz. Commentaries by Smith and Keyfitz have been brought up to date and extended by Kenneth Wachter and Herve Le Bras, giving a synoptic picture of the leading achievements in formal population studies. Like the original collection, this new edition constitutes an indispensable source for students and scientists alike, and illustrates the deep roots and continuing vitality of mathematical demography.

The book that follows is an experiment in the teaching of population theory and analysis. A sequence of problems where each is a self-contained puzzle, and the successful solution of each which puts the student in a position to tackle the next, is a means of securing the active participation of the learner and so the mastery of a technical subject. How far our questions are the exciting puzzles at which we aimed, and how far the sequence constitutes a rounded course in demography, must be left to the user to judge. One test of a good problem is whether a solution, that may take hours of cogitation, is immediately recognizable once it comes to mind. While algebraic manipulation is required throughout, we have tried to emphasize problems in which there is some substantive point-a conclusion regarding population that can be put into words. Our title, Demography Through Problems, reflects our intention of leading the reader who will actively commit him-or herself through a sequence that will not only teach definitions-in itself a trivial matter-but sharpen intuition on the way that populations behave.

ButIacceptedtheinvitation.Key?tz'ssuggestionthatweincorporatesome of my earlier work on matrix population models seemed like a good way to complement the methods presented in the book, and to expand the range of their applications. I am a demographer of plants and nonhuman animals. Some would call this an oxymoron, since the Greek rootdemos refers to people, and that's us. But there are precedents for taking more inclusive de?nitions of the Greek.Ecologyandeconomics, forexample, bothcomefromtherootoikos, referring to the household. Interpretingdemos as referring to individuals, whether they are persons or not, lets demography apply across species. There is a long tradition of such crossover. Alfred J. Lotka is acknowledged as a founding father of both demography and ecology. Raymond Pearl used demographic methods to analyze the e?ects of toxic substances and cro- ing on fruit ?ies. Lee (1987) compared the density-dependence of the vital rates of human and non-human animals. Today, in studies of senescence, reproduction, and individual heterogeneity, the boundaries between animal and human studies are becoming increasingly blurred (Wachter et al. 1997, Carey 2003, Wachter and Bulatao 2003, Carey and Tuljapurkar 2003).