- Statistic
A

**statistic**(singular) is the result of applying a function (statisticalalgorithm ) to a set of data.More formally, statistical theory defines a

**statistic**as a function of a sample where the function itself is independent of the sample's distribution: the term is used both for the function and for the value of the function on a given sample.A statistic is distinct from an unknown

statistical parameter , which is not computable from a sample. A key use of statistics is asestimator s instatistical inference , to estimate parameters of a distribution given a sample.For instance, the "sample mean" is a statistic, while the "population mean" is a parameter.**Examples**In the calculation of the

arithmetic mean , for example, the algorithm consists of summing all thedata values and dividing this sum by the number of data items. Thus the arithmetic mean is a statistic, which is frequently used as an estimator for the generally unobservablepopulation mean parameter.Other examples of statistics include

*Sample mean andsample median

*Sample variance and samplestandard deviation

* Samplequantile s besides themedian , e.g.,quartile s andpercentile s

*t statistic s,chi-square statistic s, f statistics

*Order statistic s, including sample maximum and minimum

* Sample moments and functions thereof, includingkurtosis andskewness

* Various functionals of theempirical distribution function **Properties****Observability**A

**statistic**is an "observable"random variable , which differentiates it from a "parameter", a generally unobservable quantity [*A parameter can only be computed if the entire population can be observed without error, for instance in a perfect census or on a population of*] describing a property of astandardized test takers.statistical population .Statisticians often contemplate a

parameterized family ofprobability distribution s, any member of which could be the distribution of some measurable aspect of each member of a population, from which a sample is drawn randomly. For example, the parameter may be the average height of 25-year-old men in North America. The height of the members of a sample of 100 such men are measured; the average of those 100 numbers is a**statistic**. The average of the heights of all members of the population is not a**statistic**unless that has somehow also been ascertained (such as by measuring every member of the population). The average height of "all" (in the sense of "genetically possible") 25-year-old North American men is a "parameter" and not a**statistic**.**tatistical properties**Important potential properties of statistics include completeness, consistency, sufficiency, unbiasedness,

minimum mean square error , lowvariance , robustness, and computational convenience.**Footnotes****ee also***

Statistics

*Statistical theory

*Descriptive statistics

*Statistical hypothesis testing

*Wikimedia Foundation.
2010.*

### Look at other dictionaries:

**statistic**— sta‧tis‧tic [stəˈtɪstɪk] noun STATISTICS 1. [countable usually plural] a collection of numbers that represent facts or measurements: • Statistics show that 35% of new businesses fail in their first year. • the October employment statistics… … Financial and business terms**statistic**— STATÍSTIC, Ă, statistici, ce, s.f., adj. I. s.f. 1. Evidenţă numerică, situaţie cifrică referitoare la diverse fenomene (izolate sau generale); numărătoare. 2. Culegere, prelucrare şi valorificare a unor date legate de fenomene generale. 3.… … Dicționar Român**Statistic**— Sta*tis tic (st[.a]*t[i^]s t[i^]k), Statistical Sta*tis tic*al ( t[i^]*kal), a. [Cf. F. statistique.] Of or pertaining to statistics; as, statistical knowledge; statistical tabulation. [1913 Webster] … The Collaborative International Dictionary of English**statistic**— index computation, poll (canvass) Burton s Legal Thesaurus. William C. Burton. 2006 … Law dictionary**statistic**— (n.) quantitative fact or statement, 1880; see STATISTICS (Cf. statistics) … Etymology dictionary**statistic**— ► NOUN ▪ a fact or piece of data obtained from a study of a large quantity of numerical data. ORIGIN German Statistik … English terms dictionary**statistic**— [stə tis′tik] adj. rare var. of STATISTICAL n. a statistical item or element … English World dictionary**statistic**— UK [stəˈtɪstɪk] / US noun Word forms statistic : singular statistic plural statistics 1) statistics [plural] a group of numbers that represent facts or that describe a situation New statistics show the economy is continuing to grow. Official… … English dictionary**statistic**— sta|tis|tic [ stə tıstık ] noun 1. ) statistics plural a group of numbers that represent facts or describe a situation: New statistics show the economy is continuing to grow. Official statistics underestimate the actual level of crime. statistic… … Usage of the words and phrases in modern English**statistic**— sta|tis|tic W3S2 [stəˈtıstık] n [Date: 1700 1800; : German; Origin: statistik study of political facts and figures , from Modern Latin statisticus of politics , from Latin status; STATE1] 1.) statistics a) [plural] … Dictionary of contemporary English