I have been reading a Statistics book and they show the following formula for z-score: z =

prirodnogbk 2022-07-02 Answered
I have been reading a Statistics book and they show the following formula for z-score:
z = x μ σ
And then they explain about the μ and the σ in the formula like this:

These are the mean and standard deviation of data containing the value x.

But is that so ? I don't think the mean and standard deviation should contain the value x.
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Answers (1)

Adolfo Rich
Answered 2022-07-03 Author has 9 answers
x comes from some distribution which has a fixed mean and standard deviation, determined before x was generated - you shouldn't be thinking of standard deviations and means of a finite set of numbers here.
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