qqplot

carol white <wht_crl at yahoo.com> wrote

So the conclusion is that abline(0,1) should always be used and if it doesn't go through the qqplot, the two distributions are not similar?

I think it depends what you mean by "similar".  E.g., if you mean "are both of these distributions (e.g.) normal?" then abline(0,1) is not always useful.  But if you mean "Do these have the same mean, sd, and distribution?" then abline(0,1) is the way to go.

Peter

Peter L. Flom, PhD
Statistical Consultant
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