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InDina [[statistik]], '''''mean''''' (rata-rata) mibanda dua harti:
* ''[[average]]'' basa Inggris sapopoe, leuwih cocog lamun disebut [[arithmetic mean]], dibandingkeun jeung [[geometric mean]] atawa [[harmonic mean]]. The average biasa oge disebut sample mean (rata-rata sampel).
* [[expected value]] tina [[random variable]], biasa disebut oge population mean (rata-rata populasi).
Sampel mean biasa dipake keur [[estimator]] ti [[central tendency]] saperti populasi mean. Sanajan kitu, estimator sejen oge dipake. Contona, [[median]] leuwih [[robust]] estimator keur central tendency tinimbang sampel mean.
Keur nilai-real [[randomvariabel variablerandom]] ''X'', mean nyaeta [[expected value|expectation]] ''X''.
Lamun ekspektsi euweuh, variabel random teu ngabogaan mean.
Keur [[data set]], mean ngan sakadar jumlah sakabeh observasi dibagi ku lobana observasi.
Keur ngajelaskeun ''komunal'' tina susuna data, geus ilahar dipake [[simpangan baku]] keur ngajelaskeun sabaraha beda tina observasi.
Simpangan baku ngarupakeun akar kuadrat tina ''average'' deviasi kuadrat tina mean.
The standard deviation is the square root of the average of squared deviations from the mean.
Mean ngarupakeun nilai unik ngeunaan jumlah kuadrat deviasi nu minimum.
The mean is the unique value about which the sum of squared deviations is a minimum.
IfLamun youngitung calculatejumlah thekuadrat sumdeviasi oftina squared deviations from any other measure ofukuran [[central tendency]] sejen, it willeta bebakal largerleuwih thangede fortinimang thekeur mean.
Ieu nerangkeun kunaon simpangan baku sarta mean ilahar dipake babarengan dina laporan statistik.
This explains why the standard deviation and the mean are usually cited together in statistical reports.
AnAlternatip alternativekeur measurengukur ofdispersi dispersionnyaeta is thesimpangan mean deviation, equivalentsarua to thejeung ''average'' [[absolute deviation]] from thetina mean. ItIeu iskurang lesssensitip sensitivekeur to outliers''outlier'', buttapi lesskurang tractablenurut whenwaktu combiningkombinasi datasusunan setsdata.
TheNilai mean valuetina of a functionfungsi, <math>f(x)</math>, on andina interval, <math>a<x<b</math>, canbisa also be calculateddiitung (usingngagunakeun aproses limitinglimit processdina ondefinisi thesusunan data set definition) thussaperti:
:<math>E(f(X))=\frac{\int_a^b f(x)\,dx}{b-a}.</math>
NoteCatetan, thatteu not everysakabeh [[probability distribution]] has a definedngabogaan mean oratawa [[variancevarian]] - see thetempo [[sebran Cauchy distribution]] for ankeur examplecontona.
TheDi followinghandap isngarupakeun akasimpulan summarytina ofsabaraba somemetoa ofkeur thengitung multiplememan methodstina forsusunan calculating the mean of a set ofwilangan ''n'' numbers. See theTempo [[table of mathematical symbols]] forkeur explanationsnerangkeun ofsimbol the symbolsnu useddipake.
==Aritmetik Mean==
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