Since I think that Mao Tse Tung and Pol Pot were heavy smokers, to say
nothing of Fidel Castro, I guess that where Malcolm is going is to show that
by selecting your data you can obtain any correlation you want.
The point that correlation alone does not prove causality is one that
statisticians are always making, but mention should be made of Path
Analysis, a technique based on multiple correlation, that is effective in
establishing causal pathways. It is used extensively in the social sciences,
but only rarely in ecology. I think that it deserves more attention, I have
certainly found it of value.
However a benthic ecologist I know who used Path Analysis died young, so
although that is only one data point, perhaps Path Analysis should be
avoided!
Bill Silvert
----- Original Message -----
From: "malcolm McCallum" <[email protected]>
To: <[email protected]>
Sent: sexta-feira, 4 de Dezembro de 2009 18:13
Subject: [ECOLOG-L] an example of a false correlation
Anyone who teaches stats might be interested in this false correlation I
just stumbled on.
1) Stalin did not smoke
2) Hitler did not smoke
3) Mussolini (sp?) did not smoke.
4) Roosevelt smoked
5) Churchill smoked
I guess you can see where I'm going with that!
:)
--
Malcolm L. McCallum
