Demography

Demography (from Ancient Greek δῆμος (dêmos) 'people, society' and -γραφία (-graphía) 'writing, drawing, description')[1] is the statistical study of human populations: their size, composition (e.g., ethnic group, age), and how they change through the interplay of fertility (births), mortality (deaths), and migration.

[2] Demographic analysis examines and measures the dimensions and dynamics of populations; it can cover whole societies or groups defined by criteria such as education, nationality, religion, and ethnicity.

[5] Demographic analysis estimates are often considered a reliable standard for judging the accuracy of the census information gathered at any time.

Patient demographics include: date of birth, gender, date of death, postal code, ethnicity, blood type, emergency contact information, family doctor, insurance provider data, allergies, major diagnoses and major medical history.

[citation needed] In ancient Greece, this can be found in the writings of Herodotus, Thucydides, Hippocrates, Epicurus, Protagoras, Polus, Plato and Aristotle.

[10] In Rome, writers and philosophers like Cicero, Seneca, Pliny the Elder, Marcus Aurelius, Epictetus, Cato, and Columella also expressed important ideas on this ground.

[12] One of the earliest demographic studies in the modern period was Natural and Political Observations Made upon the Bills of Mortality (1662) by John Graunt, which contains a primitive form of life table.

[14] In 1755, Benjamin Franklin published his essay Observations Concerning the Increase of Mankind, Peopling of Countries, etc., projecting exponential growth in British colonies.

[citation needed] In 1855, a Belgian scholar Achille Guillard defined demography as the natural and social history of human species or the mathematical knowledge of populations, of their general changes, and of their physical, civil, intellectual, and moral condition.

This period included a panoply of international 'great demographers' like Adolphe Quetelet (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.

[18] Demography is the statistical and mathematical study of the size, composition, and spatial distribution of human populations and how these features change over time.

Data are obtained from a census of the population and from registries: records of events like birth, deaths, migrations, marriages, divorces, diseases, and employment.

Direct data comes from vital statistics registries that track all births and deaths as well as certain changes in legal status such as marriage, divorce, and migration (registration of place of residence).

In developed countries with good registration systems (such as the United States and much of Europe), registry statistics are the best method for estimating the number of births and deaths.

They may also collect data on migration (or place of birth or of previous residence), language, religion, nationality (or ethnicity or race), and citizenship.

For example, the population size of ethnic groups or nationalities within a given society or country is subject to the same sources of change.

[31] More generally, while the basic demographic equation holds true by definition, in practice the recording and counting of events (births, deaths, immigration, emigration) and the enumeration of the total population size are subject to error.

The figure in this section shows the latest (2004) UN (United Nations) WHO projections of world population out to the year 2150 (red = high, orange = medium, green = low).

Working independently, demographers at the International Institute for Applied Systems Analysis in Austria expect world population to peak at 9 billion by 2070.

[34] Migration refers to the movement of persons from a locality of origin to a destination place across some predefined, political boundary.

[35] Demography is today widely taught in many universities across the world, attracting students with initial training in social sciences, statistics or health studies.

Being at the crossroads of several disciplines such as sociology, economics, epidemiology, geography, anthropology and history, demography offers tools to approach a large range of population issues by combining a more technical quantitative approach that represents the core of the discipline with many other methods borrowed from social or other sciences.

[citation needed] People decide to exit organizations for many reasons, such as, better jobs, dissatisfaction, and concerns within the family.

[citation needed] Problems in which demographers may be called upon to assist business organizations are when determining the best prospective location in an area of a branch store or service outlet, predicting the demand for a new product, and to analyze certain dynamics of a company's workforce.

These organizations have interests about the number and characteristics of their clients so they can maximize the sale of their products, their outlook on their influence, or the ends of their power, services, and beneficial works.