This market resolved against "Dayana Yastremska" on 2026-06-12, verified on-chain against Polymarket's settlement — the rex engine called it wrong, and logs the loss anyway.
On 2026-06-12, the rex engine's echo screen flagged this market and took "Dayana Yastremska" at 66¢ — the market was pricing that outcome at 66%, so a correct call would pay 1.53× the stake. 0.5 days later the market resolved on-chain, and the position settled as a loss: −$100.00, the full stake.
echo is one of the engine's ground-truth strategies: across 175 out-of-sample historical positions it hit 64% (95% CI 56.7–70.9%), a +13.3-point edge over the market's implied odds, returning +27.5% per bet. This position was sized with fractional Kelly from those numbers — not from a hunch.
The engine publishes its losses on purpose: a 64%-hit-rate strategy still loses 36% of the time, and any track record without losses on display is marketing, not measurement. This one is permanently archived on the losses page.
Paper-trading position settled against the gamma-api resolved outcome. This page was minted automatically when the market resolved and regenerates from the engine's ledger. Past performance does not guarantee future results. Not financial advice.