General · Bivariate · manipulative

Pearson’s r measures linear strength

Drag the cloud and watch r update — it quantifies how tightly points hug a straight trend, not how steep that trend looks.

data least-squares line

Drag any point · faint line is the least-squares fit · r recomputes from the raw cloud

Pearson r 0.00

Cloud presets

0.90
1.20

r is tightness around the line — slope is a separate control. r = 1 can be steep or shallow.

Working