Observed win rate

The number of eligible observations used to calculate a rate or performance statistic. Small samples produce less reliable estimates than larger, clearly defined samples.

The minimum win rate needed to offset losses at a stated payout. At an 80% payout it is about 55.56%.

A range expressing uncertainty around an estimated win rate or other statistic. It helps prevent a small sample from being presented as a precise result.

The probability-weighted average net result under stated win, loss, refund, and payout assumptions. A high payout alone does not establish positive expected value.

An evaluation on data that was not used to design, select, or tune a strategy. It separates development results from unseen test results.

An evaluation of fixed strategy rules against historical data using stated entry, payout, timing, and settlement assumptions. It does not prove future results.