How Is the Strength of a Correlation Determined?

By Staff WriterLast Updated Apr 6, 2020 10:02:54 PM ET
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The strength of the correlation is determined by the correlation coefficient, r. It is sometimes referred to as the Pearson product moment correlation coefficient in honor of its discoverer, Karl Pearson, who first introduced the term in 1900. There are three different formulas used to calculate this number: the raw score formula, the deviation formula or the covariance formula.