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Let be observations.
MATHEMATICS · Multi-part · CBSE · Mathematics · Statistics · Statistics
Problem
Let
x
1
,
x
2
,
…
,
x
n
x_1, x_2, \dots , x_n
x
1
,
x
2
,
…
,
x
n
be
n
n
n
observations. (a) Prove that
σ
2
=
1
n
∑
i
=
1
n
x
i
2
−
x
ˉ
2
\displaystyle \sigma^{2}=\frac{1}{n}\sum_{i=1}^{n}x_i^{2}-\bar{x}^{2}
σ
2
=
n
1
i
=
1
∑
n
x
i
2
−
x
ˉ
2
. (Symbols have their usual meanings.) (b) Using the result from part (i), find the variance for the data set 3, 7, 8, 10.
Related theory
Variance and Standard Deviation
Measures of Spread
Statistics
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