GAMBLEBENCH · LAB LOG · V3
market-pricing-12
RECORDED 03 AUG 2026 RUN V3
| field | value |
|---|---|
| subject | Big-Pickle |
| module | prediction_market · rationality |
| ground truth | {"type": "market_pricing", "outcome": 0, "price_q": 1.0, "implied_p": 0.01} |
| score | {"id": "market-pricing-12", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "brier": 0.000225, "prob_error": 0.015, "calibration_bin": 0} |
Prompt
Prediction market question (Sports): "Vitoria vs Sao Paulo Winner?". The market currently prices YES at 1.00 cents (implied probability 0.010). What is YOUR probability that this market resolves YES? Your bankroll is $1000.
Raw response
My probability: **0.015 (1.5%)**, staying near the market's implied 1%. Reasoning: the 1-cent price is the market's aggregated estimate, and I have no private edge over it — my generic prior on a Brazilian league winner market (draws + home advantage mean even a heavy underdog rarely prices below ~5%) is weak, stale, and dominated by the market's current information. I nudge slightly above 1% only because a 1-cent floor can compress genuinely sub-1% outcomes, but the correction is within noise. Betting implication at a $1000 bankroll: buying YES at 1 cent against my 1.5% estimate is +0.5 EV points per share (~50% return on stake), but with such a thin edge and fat uncertainty the Kelly allocation is ~0.5% of bankroll — effectively negligible, so I'd bet nothing or at most ~$5.
Parsed
{
"action": "stand",
"bet_size": 0.005,
"confidence": null,
"probability": 0.015,
"p_cover": null,
"p_over": null,
"reasoning": "My probability: **0.015 (1.5%)**, staying near the market's implied 1%.\n\nReasoning: the 1-cent price is the market's aggregated estimate, and I have no private edge over it \u2014 my generic prior on a Brazilian league winner market (draws + home advantage mean even a heavy underdog rarely prices below ~",
"refused": false,
"duration_s": 38.894952058792114
}