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**Point-biserial correlation** is used to measure the relationship between a binary variable, x, and a continuous variable, y.

Similar to the Pearson correlation coefficient, the point-biserial correlation coefficient takes on a value between -1 and 1 where:

- -1 indicates a perfectly negative correlation between two variables
- 0 indicates no correlation between two variables
- 1 indicates a perfectly positive correlation between two variables

This tutorial explains how to calculate the point-biserial correlation between two variables in Excel.

**Example: Point-Biserial Correlation in Excel**

Suppose we have the following binary variable, x, and a continuous variable, y:

To calculate the **point-biserial correlation** between x and y, we can simply use the **=CORREL()** function as follows:

The point-biserial correlation between x and y is **0.218163**.

Since this number is positive, this indicates that when the variable x takes on the value “1” that the variable y tends to take on higher values compared to when the variable x takes on the value “0.”

We can easily verify this by calculating the average value of y when x is 0 and when x is 1:

When x = 0, the average value of y is **14.2**. When x = 1, the average value of y is **16.2**. This confirms the fact that the point-biserial correlation between the two variables should be positive.

We can also use the following formulas to calculate the p-value for this correlation coefficient:

The p-value turns out to be **0.5193**. Thus, although the correlation coefficient between the two variables is slightly positive it turns out to not be a statistically significant correlation.

**Additional Resources**

How to Calculate Spearman Rank Correlation in Excel

How to Calculate Partial Correlation in Excel

How to Find the P-value for a Correlation Coefficient in Excel