Collect paired data values for two variables
Compute the mean of each variable
Subtract each mean from its corresponding data values
Multiply the paired deviations for each observation
Sum the products of the deviations
Square each deviation for both variables
Sum the squared deviations for each variable
Divide the sum of products by the square root of the product of the two sums of squared deviations
Use the formula: r = Σ[(x – xÌ„)(y – ȳ)] / √[Σ(x – xÌ„)² Σ(y – ȳ)²]
Interpret r as the correlation coefficient