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Chemistry

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Analytical Chemistry

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Chemical Applications of Statistical Analyses

Confidence Intervals and Sample Size

Description

Confidence intervals show a range of values around a sample mean that may contain the true mean. They are written as a probability percentage. A 95% confidence interval means the statistician is 95% confident that the true mean lies within that range.

The two ends of the range are called confiden...

Transcript

对于大量测量,标准差可靠地提供了样本均值与真实均值之间的接近度的度量。

那么,当测量值有限时,如何估计真实均值与随机数据或样本均值的接近程度呢?

置信区间是围绕平均值的统计计算值范围,其中真实平均值位于一定概率内。此区间的限制称为置信限。

真实均值的置信限是根据样本的均值、标准差和统计因子 –t– 估计的,这取决于测量次数和所需的置信区间。

随着测量值的增加,与平均值的偏差变得很小,从而导致置信区间变窄。

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