Framework
A winning streak is a fact—but not always a reliable signal. This article explains how regression to the mean applies to football, and how data and AI help distinguish solid dynamics from temporary overperformance. Foresportia is an analysis support tool: no promises, no certainties.
Introduction: streaks as a frequent trap
When a team wins five matches in a row, the instinctive conclusion is “they are on fire.” The issue: a streak can be fueled by micro-events (penalties, red cards, extreme efficiency) without any real improvement in underlying performance.
A data-driven approach avoids this illusion by focusing on underlying indicators (xG, shots, chance quality) and signal stability over time.
Why streaks fascinate us—and mislead us
- Outcome bias: overvaluing the final score while ignoring performance quality.
- Small-sample bias: 4–5 matches contain a lot of noise.
- Narrative bias: constructing explanations even when randomness is sufficient.
The statistics that really matter behind a streak
- xG for / xG against: chance creation and concession.
- Shot quality: dominance versus efficiency.
- Over/under-performance: goals scored vs expected goals.
- Opponent strength: was the streak built against weak teams?
Regression to the mean, explained simply
In statistics, exceptionally high (or low) values tend to move back toward the average unless a durable structural change exists.
In football, this often appears as:
- teams scoring far more than their xG suggests,
- temporary goalkeeper overperformance,
- clean-sheet streaks despite conceding many chances.
Conclusion: results are not enough
A winning streak can reflect genuine momentum—or a fragile overperformance. Data helps separate the two by focusing on underlying signals and accepting uncertainty.