Extreme measurements tend to be followed by more moderate ones.
Galton's 1886 finding from parents' and children's heights. It is why performance appears to improve after criticism and worsen after praise, and why almost every unbiased intervention looks effective when applied to extremes.
In practice
- A pupil who scored 92% one week and 74% the next is described as having lost focus, and nothing about the pupil changed.
- A store's worst-performing branch improves after intervention, and would have improved without it, and the intervention gets the credit.
- Standing
- The managerial sacking bounce in sport is the best-known applied case: results improve after a dismissal about as much as for clubs that keep their manager.
- Further reading
- Wikipedia
- Subject
- Science & Epistemology
- Essay
- The ways evidence misleads