Table of Contents
Population Studies
Population Studies is broadly defined as the scientific study of human populations. Major areas studied include broad population dynamics; fertility and family dynamics; health, ageing, and mortality; and human capital and labour markets. Researchers in population studies also focus on methodology. Population studies is an interdisciplinary area of study; scholars from demography, epidemiology, sociology, economics, anthropology, and various other disciplines study populations.
John Graunt is recognized as the father of demography for his systematic yet critical use of population data to investigate demographic processes. He originated a number of demographic techniques and demonstrated a healthy scepticism of his own data. Graunt was born in England in 1620. He analyzed the vital statistics of the citizens of London and wrote a book regarding those figures that greatly influenced the demographers of his day and those in the centuries that followed. It was one of the earliest demographic studies in the modern period; Natural and Political Observations Made upon the Bills of Mortality (1662), which contains a primitive form of life table.
Populations can change through three processes: Fertility, Mortality, and Migration.
Fertility involves the number of children that women have and is to be contrasted with fecundity (a woman’s childbearing potential).
Mortality is the study of the causes, consequences, and measurement of processes affecting death to members of the population. Demographers most commonly study mortality using the Life Tables.
Migration refers to the movement of persons from a locality of origin to a destination place across some pre-defined, political boundary. Migration researchers do not designate movements ‘migrations’ unless they are somewhat permanent.
At the end of the 18th century, Thomas Robert Malthus concluded that, if unchecked, populations would be subject to exponential growth. He feared that population growth would tend to outstrip growth in food production, leading to ever-increasing famine and poverty (see Malthusian catastrophe). He is seen as the intellectual father of ideas of overpopulation and the limits to growth. Later, more sophisticated and realistic models were presented by Benjamin Gompertz and Verhulst.
Mathematicians, such as Edmond Halley, developed the life table as the basis for life insurance mathematics. Richard Price was credited with the first textbook on life contingencies published in 1771, followed later by Augustus de Morgan, ‘On the Application of Probabilities to Life Contingencies’ (1838).
The period 1860-1910 can be characterized as a period of transition wherein demography emerged from statistics as a separate field of interest. This period included a panoply of international ‘great demographers’ like Adolphe Quételet (1796–1874), William Farr (1807–1883), Louis-Adolphe Bertillon (1821–1883) and his son Jacques (1851–1922), Joseph Körösi (1844–1906), Anders Nicolas Kaier (1838–1919), Richard Böckh (1824–1907), Émile Durkheim (1858-1917), Wilhelm Lexis (1837–1914), and Luigi Bodio (1840–1920) contributed to the development of demography and to the toolkit of methods and techniques of demographic analysis.
Demographic transition
Demographic transition (DT) refers to the transition from high birth and death rates to lower birth and death rates as a country or region develops from a pre-industrial to an industrialized economic system. The theory is based on an interpretation of demographic history developed in 1929 by the American demographer Warren Thompson (1887–1973), who observed changes, or transitions, in birth and death rates in industrialized societies over the previous 200 years. Most developed countries have completed the demographic transition and have low birth rates; most developing countries are in the process of this transition. Adolphe Landry of France made similar observations on demographic patterns and population growth potential around 1934. In 1949 Frank W. Notestein developed a more formal theory of demographic transition.
There are four stages to the classical demographic transition model:
Stage 1: (Pre-transition) Characterised by high birth rates, and high fluctuating death rates.
Population growth was kept low by Malthusian “preventative” (late age at marriage) and “positive” (famine, war, pestilence) checks.
Stage 2: (Early transition) During the early stages of the transition, the death rate begins to fall. As birth rates remain high, the population starts to grow rapidly.
Stage 3: (Late transition) Birth rates start to decline. The rate of population growth decelerates.
Stage 4: (Post-transition) Post-transitional societies are characterised by low birth and low death rates. Population growth is negligible or even enters a decline.
Stage 5: Total population is high but going into decline due to an ageing population. There is a continued desire for smaller families, with people opting to have children later in life. (This is not included in the original model)
Optimum Population
Optimum Population: This theory was developed by modern economists Edwin Cannan and Carr Saunders of the London School of Economics. This theory says that given the natural resources, stock of capital and the state of technical knowledge, there will be a definite size of population with the per capita income. The population which has the highest per capita income is known as the optimum population
Population Momentum
Population Momentum is the proportion between the size of a stable (unchanging) population to the total size of the initial population that experiences a drastic shift in fertility to replacement rate (2.1 children per woman). Demographers refer to population momentum as the size of the resulting stationary-equivalent population relative to the current size of the population.
Stable Population
A stable population has age-specific fertility and mortality rates that remain constant over time.
Stationary Population
It is a special example of a stable population with a zero growth rate, neither growing nor shrinking in size and is equivalent to a life table population
Lexis Diagram
Lexis Diagram (named after economist and social scientist Wilhelm Lexis) is a two-dimensional diagram that is used to represent events (such as births or deaths) that occur to individuals belonging to different cohorts. Calendar time is usually represented on the horizontal axis, while age is represented on the vertical axis.
Baby Boom
Baby Boom is a period marked by a significant increase of birth rate. This demographic phenomenon is usually ascribed within certain geographical bounds. People born during this period are often called baby boomers. The post-war population increase was first described as a Boom by Sylvia F. Porter in a column in the May 4, 1951, edition of the New York Post, based on the increase in the population of the U.S. of 2,357,000 in 1950.
Baby Bust
A sudden decline in the birthrate, especially the one in the United States and Canada from the early 1960s to the early 1980s.
Generation Jones
Generation Jones is a term coined by the author Jonathan Pontell to describe those born from approximately 1954 to 1965, while other sources place the start point at 1956 or 1957. This group is essentially the latter half of the baby boomers to the first years of Generation X.
Four generations that (probably) exist in your workplace today and the best way to address each of them: The Traditionalists (1925 to 1945): The Baby Boomers (1946 to 1964): Generation X (1965 to 1980): Generation Y (1981 to 2000).
Note : The Population Bomb is a best-selling book written by Stanford University Professor and his wife, Anne Ehrlich (who was uncredited), in 1968. It warned of mass starvation of humans in the 1970s and 1980s due to overpopulation, as well as other major societal upheavals, and advocated immediate action to limit population growth. Principles of Demography Was Written By Donald Joseph Bogue in 1969 Population As a World Problem was Written By Warren Thompson