Correlation coefficient

Definition

The correlation coefficient is a numerical measure of the strength and direction of a linear relationship between two variables. It ranges from -1 to 1, where values close to -1 or 1 indicate strong linear relationships, and values near 0 indicate weak or no linear relationship.

5 Must Know Facts For Your Next Test

1. A correlation coefficient of 1 means perfect positive linear correlation.
2. A correlation coefficient of -1 means perfect negative linear correlation.
3. A correlation coefficient of 0 indicates no linear relationship between the variables.
4. Correlation does not imply causation; it only measures the strength and direction of a relationship.
5. Pearson's correlation coefficient is the most commonly used method for calculating the correlation between two continuous variables.

Review Questions

• What does a correlation coefficient of -0.8 indicate about the relationship between two variables?
• How would you interpret a correlation coefficient of 0?
• Why is it important to remember that correlation does not imply causation?

Related terms

Scatter Plot: A graphical representation showing the relationship between two numerical variables using dots.

Regression Line: A line that best fits the data points on a scatter plot, used to model the relationship between variables.

Causation:

Indicates that one event is the result of the occurrence of another event; there is a cause-and-effect relationship.