What is the variance of {-2, 5, 18, -8, -10, 14, -12, 4}?

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Answer 1 · 2016-03-15T11:00:27

Variance $sigma^2=6903/64=107.8593$

compute the arithmetic mean $mu$ first

$n=8$

$mu=(-2+5+18+(-8)+(-10)+14+(-12)+4)/8$

$mu=(-32+41)/8$

$mu=9/8$

compute the variance $sigma^2$ using the variance formula for population

$sigma^2=(sum(x-mu)^2)/n$

$sigma^2=((-2-9/8)^2+(5-9/8)^2+(18-9/8)^2+(-8-9/8)^2+(-10-9/8)^2+(14-9/8)^2+(-12-9/8)^2+(4-9/8)^2)/8$

$sigma^2=6903/64$

$sigma^2=107.8593$

God bless ....I hope the explanation is useful.