An Introduction to Demography

Abstract

WHAT IS DEMOGRAPHY? This book is an introduction to demography . A short definition of demography is the systematic and scientific study of human populations. The word demography comes from the Greek words δημος ( demos ) for “population” and γραφια ( graphia ) for “description” or “writing,” thus the phrase, “writings about population.” The term demography was first used in 1855 by the Belgian statistician Achille Guillard in his book Elements of Human Statistics or Comparative Demography (Borrie, 1973: 75; Rowland, 2003: 16). Most demographers (Hauser and Duncan, 1959; McFalls, 2007; Micklin and Poston, 2005) agree about the objectives and definition of demography. Demography is the social science that studies: (1) the size, composition, and distribution of the human population of a given area at a specific point in time; (2) the changes in population size and composition; (3) the components of these changes ( fertility , mortality , and migration ); (4) the factors that affect these components; and (5) the consequences of changes in population size, composition, and distribution, or in the components themselves. Hence, demography may be more broadly defined as the scientific study of the size, composition, and distribution of human populations and their changes resulting from fertility, mortality, and migration. Demography is concerned with how large (or how small) are the populations; how the populations are composed according to age, sex, race, marital status, and other characteristics; and how the populations are distributed in physical space (e.g., how urban and rural they are) (Bogue, 1969). Demography is also interested in the changes over time in the size, composition, and distribution of human populations, and how these result from the processes of fertility, mortality, and migration. The chapters of this book discuss these topics in much more depth and detail and will provide you with a thorough introduction to demography. I will start this first chapter with the following point: every one of us, you and I, whether we are aware of it or not, have already contributed, and will continue to contribute throughout our lives, to the subject matter of demography. I will next elaborate on the definition of demography introduced above.