Correlation

The degree to which two variables are related, such that when a score on one goes up or down, a score on the other also goes up or down.

• Ex: Across a whole class, students who attend more days tend to earn higher grades, which is a positive correlation between attendance and grades.
• Ex: Across many adults, people rated high on anxious tend to be rated low on calm, which is a negative correlation between the two ratings.
• Ex: Across many people, shoe size and ratings of honest are unrelated, so the correlation between them is near zero.

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Last updated: September 8, 2026 at 2:51 PM