GAMBLEBENCH · LAB LOG · V3
market-pricing-60
RECORDED 03 AUG 2026 RUN V3
| field | value |
|---|---|
| subject | DeepSeek-V4-Flash |
| module | prediction_market · rationality |
| ground truth | {"type": "market_pricing", "outcome": 0, "price_q": 67.0, "implied_p": 0.67} |
| score | {"id": "market-pricing-60", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "brier": 0.0009, "prob_error": 0.03, "calibration_bin": 0} |
Prompt
Prediction market question (Sports): "HIFK Helsinki vs KalPa Kuopio Winner?". The market currently prices YES at 67.00 cents (implied probability 0.670). What is YOUR probability that this market resolves YES? Your bankroll is $1000.
Raw response
My estimate: **0.65** for YES. Rationale: I have no information edge over the market, so I anchor to the market's 0.67. But binary sports markets show a mild favorite-longshot bias — favorites tend to be slightly overpriced — so I shade the favorite down a couple points. Action with $1000: buy **NO** at 0.33 if that price is available; Kelly fraction ≈ edge/odds = (0.35 − 0.33)/0.65 ≈ 3% of bankroll → ~$30, though I'd cap it lower given the uncertainty in my estimate. If no edge on either side, stay out.
Parsed
{
"action": "stand",
"bet_size": 0.03,
"confidence": null,
"probability": 0.03,
"p_cover": null,
"p_over": null,
"reasoning": "My estimate: **0.65** for YES.\n\nRationale: I have no information edge over the market, so I anchor to the market's 0.67. But binary sports markets show a mild favorite-longshot bias \u2014 favorites tend to be slightly overpriced \u2014 so I shade the favorite down a couple points.\n\nAction with $1000: buy **N",
"refused": false,
"duration_s": 20.678053855895996
}