Median in the context of "Regression coefficient"

Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surface area. With nearly 1.4 billion people as of 2021, it accounts for about 18% of the world's human population. Africa's population is the youngest among all the continents; the median age in 2012 was 19.7, when the worldwide median age was 30.4. Based on 2024 projections, Africa's population will exceed 3.8 billion people by 2100. Africa is the least wealthy inhabited continent per capita and second-least wealthy by total wealth, ahead of Oceania. Scholars have attributed this to different factors including geography, climate, corruption, colonialism, the Cold War, and neocolonialism. Despite this low concentration of wealth, recent economic expansion and a large and young population make Africa an important economic market in the broader global context, and Africa has a large quantity of natural resources.

Africa straddles the equator and the prime meridian. The continent is surrounded by the Mediterranean Sea to the north, the Arabian Plate and the Gulf of Aqaba to the northeast, the Indian Ocean to the southeast and the Atlantic Ocean to the west. France, Italy, Portugal, Spain, and Yemen have parts of their territories located on African geographical soil, mostly in the form of islands.

Wealth is the abundance of valuable financial assets or physical possessions which can be converted into a form that can be used for transactions. This includes the core meaning as held in the originating Old English word weal, which is from an Indo-European word stem. The modern concept of wealth is of significance in all areas of economics, and clearly so for growth economics and development economics, yet the meaning of wealth is context-dependent. A person possessing a substantial net worth is known as wealthy. Net worth is defined as the current value of one's assets less liabilities (excluding the principal in trust accounts).

At the most general level, economists may define wealth as "the total of anything of value" that captures both the subjective nature of the idea and the idea that it is not a fixed or static concept. Various definitions and concepts of wealth have been asserted by various people in different contexts. Defining wealth can be a normative process with various ethical implications, since often wealth maximization is seen as a goal or is thought to be a normative principle of its own. A community, region or country that possesses an abundance of such possessions or resources to the benefit of the common good is known as wealthy.

The national average salary (or national average wage) is the mean salary for the working population of a nation. It is calculated by summing all the annual salaries of all persons in work (surveyed) and dividing the total by the number of workers (surveyed). It is not the same as the Gross domestic product (GDP) per capita, which is calculated by dividing the GDP by the total population of a country, including the unemployed and those not in the workforce (e.g. retired people, children, students, etc.). It can be useful in understanding economic conditions, and to employers and employees in negotiating salaries. The national median salary is usually significantly less than the national average salary because the distribution of workers by salary is skewed.

The median income is the income amount that divides a population into two groups, half having an income above that amount, and half having an income below that amount. It may differ from the mean (or average) income. Both of these are ways of understanding income distribution. Median income can be calculated by household income, by personal income, or for specific demographic groups. When taxes and mandatory contributions are subtracted from income, the result is called net or disposable income. The measurement of income from individuals and households, which is necessary to produce statistics such as the median, can pose challenges and yield results inconsistent with aggregate national accounts data. For example, an academic study on the Census income data claims that when correcting for underreporting, U.S. median gross household income was 15% higher in 2010 (table 3).

This is a list of countries of the world by wealth per adult, from UBS's Global Wealth Databook. Wealth includes both financial and non-financial assets.

UBS publishes various statistics relevant for calculating net wealth. These figures are influenced by real estate prices, equity market prices, exchange rates, liabilities, debts, adult percentage of the population, human resources, natural resources and capital and technological advancements, which may create new assets or render others worthless in the future.

Rape is a type of sexual assault involving sexual intercourse, or other forms of sexual penetration, carried out against a person without their consent. The act may be carried out by physical force, coercion, abuse of authority, or against a person who is incapable of giving valid consent, such as one who is unconscious, incapacitated, has an intellectual disability, or is below the legal age of consent (statutory rape). The wrongness of the rape is not merely or, on many occasions even primarily, the violence against the body of the victim but the violence against the very person of the victim. The term rape is sometimes casually used interchangeably with the term sexual assault.

The rate of reporting, prosecuting and convicting for rape varies between jurisdictions. Internationally, the incidence of rapes recorded by the police during 2008 ranged, per 100,000 people, from 0.2 in Azerbaijan to 92.9 in Botswana with 6.3 in Lithuania as the median. Worldwide, reported instances of sexual violence, including rape, are primarily committed by males against females. Rape by strangers is usually less common than rape by people the victim knows, and male-on-male prison rapes are common and may be the least reported forms of rape.

In statistics and probability, quantiles are cut points dividing the range of a probability distribution into continuous intervals with equal probabilities or dividing the observations in a sample in the same way. There is one fewer quantile than the number of groups created. Common quantiles have special names, such as quartiles (four groups), deciles (ten groups), and percentiles (100 groups). The groups created are termed halves, thirds, quarters, etc., though sometimes the terms for the quantile are used for the groups created, rather than for the cut points.

q-quantiles are values that partition a finite set of values into q subsets of (nearly) equal sizes. There are q − 1 partitions of the q-quantiles, one for each integer k satisfying 0 < k < q. In some cases the value of a quantile may not be uniquely determined, as can be the case for the median (2-quantile) of a uniform probability distribution on a set of even size. Quantiles can also be applied to continuous distributions, providing a way to generalize rank statistics to continuous variables (see percentile rank). When the cumulative distribution function of a random variable is known, the q-quantiles are the application of the quantile function (the inverse function of the cumulative distribution function) to the values {1/q, 2/q, …, (q − 1)/q}.

In probability theory and statistics, a normal distribution or Gaussian distribution is a type of continuous probability distribution for a real-valued random variable. The general form of its probability density function is$${\displaystyle f(x)={\frac {1}{\sqrt {2\pi \sigma ^{2}}}}e^{-{\frac {(x-\mu )^{2}}{2\sigma ^{2}}}}\,.}$$

The parameter ⁠${\displaystyle \mu }$⁠ is the mean or expectation of the distribution (and also its median and mode), while the parameter ${\textstyle \sigma ^{2}}$ is the variance. The standard deviation of the distribution is ⁠${\displaystyle \sigma }$⁠ (sigma). A random variable with a Gaussian distribution is said to be normally distributed and is called a normal deviate.