3 ms·

I know. Did anyone see the r^2 for the correlation?

• Shamiq 17y ago
  I was taught by an econometrician that r^2 values don't mean much, but I cannot remember his logic as to why. Maybe something about malleability?
  • tel 17y ago
    That Anscombe example sheds light on the misuse of r^2. All of those examples have the same r^2 value.
    • joeyo 17y ago
      Those are some very nice examples. However, is there a better/more respected metric for comparing how two datasets are related? Mutual Information perhaps?
      • tel 17y ago
        I'm not an expert -- more of a hobbyist who is actively trying to improve my statistical chops -- but I don't think there's ever a general metric for this sort of thing. For any statistic it's important to demonstrate that it's being used as intended so that its lay translation means what it seems to mean. I mean, r^2 isn't all that misleading if your relation really is linear. R^2 plus a graph of the regression would be sufficient. Just taking a look at the residuals of the Anscombe sets easily shows that linear fitting (thus r^2) is inappropriate for sets 2-4. (btw: if you fit the second Anscombe data set with a 2nd order polynomial, r^2 = 1. Of course, it's pretty clear that there's hardly any error in that set.)