0
$\begingroup$

I am comparing 2 variables and have an outlier in x of 82.27. I want to find the z score of this outlier. When using the z score equation x-mean/standard deviation, do I use the mean and standard deviation of my x values or y values?

$\endgroup$

1 Answer 1

Reset to default
1
$\begingroup$

If the observation of 82.27 belongs to the variable $x$, then we use the mean and standard deviation for $x$ to find the $z$-score: $$z=\frac{x-\mu_x}{\sigma_x}=\frac{82.27-\mu_x}{\sigma_x}$$

$\endgroup$
2
  • $\begingroup$ If my observation was part of the variable y would I just use the mean and stdv of y? $\endgroup$
    – Joe
    Commented Jul 24, 2021 at 5:12
  • $\begingroup$ @Joe that's correct $\endgroup$
    – 5201314
    Commented Jul 24, 2021 at 17:45

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .