Population
A population is the complete set group of individuals, whether that group comprises a nation or a group of people with a common characteristic. In statistics, a population is the pool of individuals from which a statistical sample is drawn for a study. Thus, any selection of individuals grouped by a common feature can be considered a population. A sample may also refer to a statistically significant portion of a population, not an entire population. For this reason, a statistical analysis of a sample must report the approximate standard deviation, or standard error, of its results from the entire population. Only an analysis of an entire population would have no standard error. In ordinary usage, a population is a distinct group of individuals with shared citizenship, identity, or characteristics. In statistics, a population is a representative sample of a larger group of people (or even things) with one or more characteristics in common. The members of a sample population must be randomly selected for the study's results to reflect the whole accurately. The U.S. Census is the most ambitious survey since it entails a door-to-door canvas of the entire population rather than a sample group study. Population surveys, large and small, inform many, if not most, decisions by government and businesses [Investopedia]. According to the UN, the world's population surpassed 8 billion on 15 November 2022, and 7 billion was surpassed on 12 March 2012. According to a separate estimate by the United Nations, Earth's population exceeded seven billion in October 2011, a milestone that offers unprecedented challenges and opportunities to all of humanity, according to UNFPA. According to papers published by the United States Census Bureau, the world population hit 6.5 billion on 24 February 2006.
The United Nations Population Fund designated 12 October 1999 as the approximate day on which the world population reached 6 billion. This was about 12 years after the world population reached 5 billion in 1987 and six years after the world population reached 5.5 billion in 1993. The population of countries such as Nigeria is unknown to the nearest million, so there is a considerable margin of error in such estimates. Researcher Carl Haub calculated that over 100 billion people have probably been born in the last 2000 years[Wikipedia].
Population Definition in Statistics and How to Measure It. Investopedia. Retrieved from: https://www.investopedia.com/terms/p/population.asp
Population (2022, June 16). Biology online. URL: http://www.biology-online.org/dictionary/Population