Regression to the Mean

Why extremes don’t last

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• When outcomes mix skill and luck, extreme results tend to be followed by less extreme ones.
• This regression to the mean creates illusory “jinxes” and illusory cures.
• Controlled comparisons are needed to tell real effects from regression.

Steps

1. Skill plus luck
2. The cover jinx
3. How far back?
4. Galton’s puzzle
5. Mostly luck
6. Praise and blame