common.common.examples.exampleNumber
\(\text{Study hours: } [2,3,4,5,6], \text{ Test scores: } [65,75,80,90,95] \rightarrow r = 0.99\)
Correlation Calculator
Calculate Pearson and Spearman correlation coefficients
Results
Enter values and click Calculate to see the result.
Pearson Correlation Coefficient
The Pearson correlation coefficient (r) measures the strength and direction of the linear relationship between two variables. It ranges from -1 to +1:
- r = +1: Perfect positive linear relationship
- r = -1: Perfect negative linear relationship
- r = 0: No linear relationship
- 0.7 ≤ |r| < 1: Strong correlation
- 0.5 ≤ |r| < 0.7: Moderate correlation
- 0.3 ≤ |r| < 0.5: Weak correlation
- |r| < 0.3: Very weak or no correlation
Important: Correlation does not imply causation. A high correlation between two variables does not mean that one causes the other. Always consider other factors and the context of your data.
\(r = \frac{\sum(x_i - \bar{x})(y_i - \bar{y})}{\sqrt{\sum(x_i - \bar{x})^2 \sum(y_i - \bar{y})^2}}, R^2 = r^2\)
Worked Examples
common.common.examples.exampleNumber
\(\text{Temperature: } [10,15,20,25,30], \text{ Ice cream sales: } [100,150,200,250,300]\)