Pearson's r measures linear association — from −1 (perfectly inverse) through 0 (no linear pattern) to +1 (perfectly aligned). Drag the slider and watch the cloud morph.
Target r+0.70
Observed r—
Interpretation—
Watch out: r only captures linear association. A perfect parabola can have r ≈ 0. And correlation is not causation — both variables could be driven by a third.