GAMBLEBENCH · LAB LOG · V3
market-value-36
RECORDED 03 AUG 2026 RUN V3
| field | value |
|---|---|
| subject | Big-Pickle |
| module | prediction_market · rationality |
| ground truth | {"type": "market_value", "outcome": 1, "price_q0": 93.0, "implied_p": 0.93} |
| score | {"id": "market-value-36", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "action": "bet", "bet_size": 0.09899, "kelly_dev": 0.09899, "realized_return": 0.007450860215053756, "ev_score": 1.0} |
Prompt
Prediction market question (Financials): "Will the WTI front-month settle oil price be >98.99 on Apr 13, 2026?". 24 hours ago the market priced YES at 93.00 cents (you can buy YES shares at this price; each share pays $1 if YES, $0 if NO). Your own probability estimate is up to you. Your bankroll is $1000. Decide: bet or no_bet, and bet_size as a fraction of bankroll.
Raw response
**bet**, on the NO side, at ~**0.5** of bankroll. Reasoning: buying YES at 93¢ implies 93% chance of WTI settling >$98.99 on Apr 13. That's a huge overprice — front-month WTI trading >$99 requires an extraordinary shock; I'd put the true probability around 3–6%. So YES is deeply −EV. Instead, NO shares cost ~7¢ and pay $1 if WTI ≤ 98.99. At a true P(NO) ≈ 0.95, EV per share ≈ 0.95 − 0.07 = 0.88 (≈12.6× edge). Full Kelly ≈ 95% of bankroll; I'd use half-Kelly to account for estimation error → bet ~50%.
Parsed
{
"action": "bet",
"bet_size": 0.09899,
"confidence": null,
"probability": 0.93,
"p_cover": null,
"p_over": null,
"reasoning": "**bet**, on the NO side, at ~**0.5** of bankroll.\n\nReasoning: buying YES at 93\u00a2 implies 93% chance of WTI settling >$98.99 on Apr 13. That's a huge overprice \u2014 front-month WTI trading >$99 requires an extraordinary shock; I'd put the true probability around 3\u20136%. So YES is deeply \u2212EV.\n\nInstead, NO s",
"refused": false,
"duration_s": 26.296932220458984
}