( ′päp·yə′lā·shən ′kär·ə′lā·shən ′kō·ə′fish·ənt
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The strength of the linear relationship between the two variables in the regression equation is the correlation coefficient, r, and is always a value between 1 and 1, inclusive.
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Correlation coefficient is a statistic representing how closely two variables covary; it can vary from 1 (perfect negative correlation) through 0 More?
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I'm not an expert either but as an experiment I just plotted La Niña years from 1951 to 2001 against Annual Global Temperature Anomalies and got a correlation coefficient of
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