# Chance this is luck

The odds that the winner you picked was luck.

The probability of backtest overfitting, PBO.

This check was called Probability of overfitting.

## Pass level

- Chance this is luck: at most 50%
- Blocks the history is cut into: 16

Thresholds version 1.19.0

A test that stops at this check reads Killed at the expensive tier.

- [Forge help ↗](https://oathra.app/en/forge/methods#chance-this-is-luck)