プラン

標準偏差の計算機

数を入力し、母集団か標本かを選んでください。

2 つ以上の値（カンマかスペースで区切る）

結果

値を入力して「計算」を押すと結果が表示されます。

公式

σ=∑(xi−μ)2n\sigma = \sqrt{\frac{\sum (x_i - \mu)^2}{n}}

Population standard deviation.

s=∑(xi−xˉ)2n−1s = \sqrt{\frac{\sum (x_i - \bar{x})^2}{n - 1}}

Sample standard deviation uses n − 1 (Bessel’s correction).

この計算ツールの使い方

  1. Enter the data and choose population if it is the whole group, or sample if it is part of a larger group.
  2. Press Calculate.

解き方付き例題

Population: 2, 4, 4, 4, 5, 5, 7, 9

The mean is 5 and the squared deviations add up to 32.

Variance = 32 / 8 = 4, so the standard deviation is √4 = 2.

よくある質問

Population or sample?

Use population when you have every member of the group; use sample when your data is a subset used to estimate the whole.

What does standard deviation tell me?

How far values typically are from the mean. Larger means more spread out.

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