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Chemistry

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Analytical Chemistry

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Chemical Applications of Statistical Analyses

Measuring and Reporting Uncertainty

Description

Uncertainty is part of analytical chemistry measurement. When repeated measurements are taken, random errors can cause the results to differ in small ways. These repeated values are compared with the estimated or expected value to judge how much uncertainty is present.

Uncertainty is usually writ...

Transcript

不确定性反映了测量结果可能存在的值范围。

但是,不确定性因误差而异,误差是测量结果与真实值之间的差异。

对于它的表示,值的不确定性放在结果大小的右侧,以有效数字表示。

有效数字是在不损失精度的情况下表示结果所需的位数。有效数字的数量包括其右侧的所有确定性数字和不确定性数字。

不确定性可以用绝对和相对尺度表示。

绝对不确定性是结果在两个方向上的可能变异幅度。相反,相对不确定性是绝对不确定性与结果量级的比率。

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