Correlation coefficient calculator
Calculate Pearson's r — measures the strength and direction of the linear relationship between two variables.
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Interpreting r
r = 1: Perfect positive correlation. r = −1: Perfect negative. r = 0: No linear relationship.
|r| > 0.7: strong. 0.3–0.7: moderate. < 0.3: weak.
Correlation ≠ causation
A strong correlation doesn't prove one variable causes the other. Ice cream sales and drowning are correlated — both increase in summer — but neither causes the other.
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