# Arithmetic mean

In mathematics and statistics, the arithmetic mean or arithmetic average, or simply just the mean or the average, is the sum of a collection of numbers divided by the count of numbers in the collection. The collection is often a set of results of an experiment or an observational study, or frequently a set of results from a survey. The term "arithmetic mean" is preferred in some contexts in mathematics and statistics, because it helps distinguish it from other means, such as the geometric mean and the harmonic mean.

- Indecomposable distribution
- In probability theory, an indecomposable distribution is a probability distribution that cannot be represented as the distribution of the sum of two or more non-constant independent random variables: Z ≠ X + Y. If it can be so expressed, it is
- Central tendency
- In statistics, a central tendency is a central or typical value for a probability distribution. It may also be called a center or location of the distribution. Colloquially, measures of central tendency are often called averages. The term central tendency
- Idempotent analysis
- In mathematical analysis, idempotent analysis is the study of idempotent semirings, such as the tropical semiring. The lack of an additive inverse in the semiring is compensated somewhat by the idempotent rule
- Coprime integers
- In mathematics, two integers a and b are coprime, relatively prime or mutually prime if the only positive integer that is a divisor of both of them is 1. Consequently, any prime number that divides a does not divide b, and vice versa. This is equivalent
- Lebesgue integrability
- In mathematics, Lebesgue integrability may refer to:Whether the Lebesgue integral of a function is defined; this is what is most often meant.
The Lebesgue integrability condition, which determines whether the Riemann integral of a function is defined
- Direct limit of groups
- In mathematics, a direct limit of groups is the direct limit of a direct system of groups. These are central objects of study in algebraic topology, especially stable homotopy theory and homological algebra. They are sometimes called stable groups, though
- Rankit
- In statistics, rankits of a set of data are the expected values of the order statistics of a sample from the standard normal distribution the same size as the data. They are primarily used in the normal probability plot, a graphical technique for
- PDIFF
- In geometric topology, PDIFF, for piecewise differentiable, is the category of piecewise-smooth manifolds and piecewise-smooth maps between them. It properly contains DIFF and PL, and the reason it is defined is to allow one to relate these two categories
- Errors and residuals
- In statistics and optimization, errors and residuals are two closely related and easily confused measures of the deviation of an observed value of an element of a statistical sample from its "theoretical value". The error of an observed value is the
- Cold Water Cemetery
- Cold Water Cemetery (CWC), also known as the Sinks and the Patterson Family Cemetery, is a historic cemetery located at 15290 Old Halls Ferry Road in Florissant, St. Louis County, Missouri. The cemetery is 1.5 acres and was historically most active