Sample Size

The number of bets behind a record. Small samples are dominated by variance and can look great or terrible by luck alone; a track record only becomes meaningful over hundreds of graded bets.

• Variance — The luck-driven swing of results around their long-run expectation. Even +EV bettors have losing stretches from it.
• Win Rate — The share of settled bets that won (pushes and voids excluded). Read alongside ROI and units — a high win rate on heavy favorites can still lose money.