Pearson Correlation
Example | Calculator
Formula
 x = individual scores in group X y = individual scores in group Y n = number of pairs of scores x = individual scores M = mean N= number of scores in group

Steps

Create five columns: "x", "(x-Mx)2", "y", "(y-My)2", "xy"
1. Put the raw data for group X in column x, and for group Y in column y
2. Calculate the mean for both groups
3. Calculate deviation scores for each group by subtracting each score from it's group mean and squaring it and put these in the columns "(x-Mx)2" and "(y-My)2"
4. Sum the squared deviation scores for each group
5. Multiply each pair of scores and put the result in column "xy"
6. Sum "xy" scores
7. Calculate s for each group
8. Set up formula
9. Calculate r
10. Check to see if r is statistically significant on probability table with df = n-2 and p < .05

Example

Practice by creating your own data and then check your work with the Virtual Statistician Pearson Correlation Calculator
(Only works with n = 8)

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