計(jì)算標(biāo)準(zhǔn)偏差
標(biāo)準(zhǔn)偏差（Standard Deviation，SD）是樣本平均數(shù)方差的開平方，它反映組內(nèi)個(gè)體間的離散程度。其計(jì)算公式為
SD = \sqrt{\frac{\sum_{i = 1}^{n}(x_{i}-\bar{x})^{2}}{n – 1}}
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，其中
二、基于標(biāo)準(zhǔn)誤差計(jì)算誤差棒
計(jì)算標(biāo)準(zhǔn)誤差
標(biāo)準(zhǔn)誤差（Standard Error，SE）表示的是抽樣的誤差。其計(jì)算公式為
SE=\frac{SD}{\sqrt{n}}
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，其中
三、基于置信區(qū)間計(jì)算誤差棒
確定置信水平和相應(yīng)系數(shù)
常見的置信水平有95%，對(duì)應(yīng)的常數(shù)系數(shù)在大樣本情況下約為1.96（不同的樣本量和分布情況可能會(huì)有不同的系數(shù)值）。
計(jì)算置信區(qū)間
若基于標(biāo)準(zhǔn)偏差計(jì)算，置信區(qū)間的計(jì)算公式為
\bar{x}\pm z\times\frac{SD}{\sqrt{n}}
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