- #26

FactChecker

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What is a measurement "campaign"?I learned that the mean value of a measurement is a pretty good measurement for the "true value" of one single measurement campaign. The standard deviation gives you trust intervals for the reliabilty of a single measurement campaign, nothing else.

Where did this come from?Now with the variances ##s^2(y_i)## we get $$s^2(\bar{y})=\left(\frac{1}{N}\right)^2 \left( s^2\left(y_1\right)+s^2\left(y_1\right)+\dots+s^2\left(y_N\right)\right) $$.

In its simplest form, aren't you saying that this formula for a sample standard deviation is wrong?

## s = \sqrt {\frac {\sum_{i=1}^{N} {(x_i-\bar x)^2}}{N-1}} ##