Repeatability is estimated by calculating standard deviation using repeated measured data.
But there is the case that we want to know repeatability without such data. It is the case that repeating is difficult. In this case Measured data is useful.
For example, there is a data set of 5 samples measured by A and B.
And that of standard deviation.
Standard deviation 2.1 for A and 2.2 for B are sums of errors of samples and repeatability.
Then difference of repeatability A and B is calculated.
(1)
Calculate the difference of A and B.
Then calculate standard deviation of this difference.
Meaning this standard deviation is below.
(2)
At this point we can see the goal.
We can get the value of repeatability using the upper formlations (1) and (2).
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Use Double Measured Data for Pattern Recognition
