# Central tendency

Central or typical value for a probability distribution.

- Central tendency61 related topics

## Statistical dispersion

Extent to which a distribution is stretched or squeezed.

Dispersion is contrasted with location or central tendency, and together they are the most used properties of distributions.

## Average

Average is a single number taken as representative of a list of numbers, usually the sum of the numbers divided by how many numbers are in the list .

The mode, the median, and the mid-range are often used in addition to the mean as estimates of central tendency in descriptive statistics.

## Median

Value separating the higher half from the lower half of a data sample, a population, or a probability distribution.

The median is 2 in this case, (as is the mode), and it might be seen as a better indication of the center than the arithmetic mean of 4, which is larger than all-but-one of the values.

## Level of measurement

Classification that describes the nature of information within the values assigned to variables.

The mode, i.e. the most common item, is allowed as the measure of central tendency for the nominal type.

## Outlier

Outlier is a data point that differs significantly from other observations.

Estimators capable of coping with outliers are said to be robust: the median is a robust statistic of central tendency, while the mean is not.

## Statistics

Discipline that concerns the collection, organization, analysis, interpretation, and presentation of data.

Descriptive statistics are most often concerned with two sets of properties of a distribution (sample or population): central tendency (or location) seeks to characterize the distribution's central or typical value, while dispersion (or variability) characterizes the extent to which members of the distribution depart from its center and each other.

## Arithmetic mean

Sum of a collection of numbers divided by the count of numbers in the collection.

While the arithmetic mean is often used to report central tendencies, it is not a robust statistic, meaning that it is greatly influenced by outliers (values that are very much larger or smaller than most of the values).

## Mid-range

In statistics, the mid-range or mid-extreme is a measure of central tendency of a sample (statistics) defined as the arithmetic mean of the maximum and minimum values of the data set:

## Frequency (statistics)

Event of times the observation occurred/recorded in an experiment or study.

This assessment involves measures of central tendency or averages, such as the mean and median, and measures of variability or statistical dispersion, such as the standard deviation or variance.

## Interquartile range

Measure of statistical dispersion, which is the spread of the data.

The median is the corresponding measure of central tendency.