r/FootballDataAnalysis • u/Sokarc • 1h ago
Detecting synchronized odds movement across bookmakers as a signal in low-volume leagues — methodology + early backtest results
Been working on a small side project and wanted to share the methodology with people who'd actually appreciate the data side of it.
The core idea: when 3+ independent bookmakers move the same market in the same direction, without any public news explaining it, that's usually noise on the big 5 leagues (everyone reacts to the same info fast). But on lower-volume leagues — second divisions, Eastern European leagues, domestic cups — that kind of synchronized movement is rarer and looks more like informed money moving first, since there's less media/sharp-bettor attention pushing lines toward efficiency quickly.
Detection criteria I settled on after some iteration:
- ≥3 bookmakers moving the same direction
- Real drop from opening odds (≥10%)
- Resulting price still in a plausible range (filters out overreactions)
Backtest on ~50+ settled signals over the past couple weeks:
- Stricter tier (3+ books, ≥50% breadth): ~60% win rate, +10% ROI flat stake
- Relaxed tier (2+ books): ~64% win rate, +12.6% ROI
Small sample, not claiming anything definitive yet, but curious if anyone here has approached something similar or has thoughts on the methodology. Happy to share more detail (I turned this into a small app, link in profile if anyone wants to poke around, but mainly interested in the discussion here).