Re: 'BTW, for your story about the cat: In a statistical sense, the head predicts the tail. Quite a difference from the head causes the tail.'
Unless the cat is walking backwards. It is the word causation that is the problem. X is positively associated with Y does not mean (and never means /or proves) X causes Y. Also note the need for confidence bands and sample size determinations (or at least how many X,Y pairs were used) in concluding there is even a relationship. How many years and look at how much data was needed in the smoking/lung cancer relationship, never mind causation. Ling Ling Huang Sacramento City College --- On Thu, 10/11/12, David L. McNeely <[email protected]> wrote: From: David L. McNeely <[email protected]> Subject: Re: [ECOLOG-L] correlation v. causation To: [email protected] Date: Thursday, October 11, 2012, 6:27 AM ---- Miles Medina <[email protected]> wrote: > > Also, I would add, in response to a comment above.. someone said > correlation implies causation. Yes it may, of course, but let's not forget > that there could be a third variable that causes the two correlated ones > originally in question. I believe that the meaning of what was originally stated was that correlation suggests a possibility, not that it implies or infers causation. Certainly we all know about the false reasoning that allows us to believe in causation due to correlation, when the relationship is simply coincidental. BTW, for your story about the cat: In a statistical sense, the head predicts the tail. Quite a difference from the head causes the tail. David McNeely
