Correlation & Trend Lines Unit 5 Correlation & Trend Lines

Correlation The relationship between two things (x, y) x is the independent (explanatory) variable y is the dependent (response) variable

Correlation Coefficient Measure of the strength and the direction of a linear relationship. -1 < r < 1

About r

Strong Positive 0.8 < r < 1

Moderate Positive 0.5 < r < 0.8

Weak Positive 0.2 < r < 0.5

Strong Negative -1 < r < 0.8

Moderate Negative -0.8 < r < -0.5

Weak Negative -0.5 < r < -0.2

No Correlation -0.2 < r < 0.2