correlation

Definitions

1. A statistical measure (typically Pearson's r, ranging from -1 to +1) that quantifies the strength and direction of the linear relationship between two variables. A correlation of +1 means perfect positive association, -1 means perfect inverse association, and 0 means no linear relationship. Crucially, correlation does not imply causation.

   In plain English: A measure of how much two things tend to move together. When one goes up and the other goes up too, they are correlated — but that does not mean one causes the other.

   Example: Ice cream sales and drowning deaths have a strong positive correlation — not because ice cream causes drowning, but because both spike in summer.

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