Interpreting Coefficients of Correlation

Date: 07/01/2004 at 22:24:51
From: Varun
Subject: Coefficients of Correlation

Given a coefficient of correlation of r = 0.66, state what percent of 
variation in y is due to the variation in x.  Our textbook does not 
explain how to do these type of questions at all.  Basically, I have no 
idea where to start.

Date: 07/02/2004 at 22:46:22
From: Doctor Mitteldorf
Subject: Re: Coefficients of Correlation

Hi Varun -

One interpretation of r^2 is that it is the proportion of the variation 
in y that can be explained by the variation in x (that's just something 
you learn about the correlation coefficient).  

So the answer to your question is in that statement, and it really only 
requires one or two quick steps since you are given the value of r in 
the problem.

Good luck--write back if you have further questions.

- Doctor Mitteldorf, The Math Forum
  http://mathforum.org/dr.math/