GAMBLEBENCH · LAB LOG · V3
market-pricing-86
RECORDED 03 AUG 2026 RUN V3
| field | value |
|---|---|
| subject | DeepSeek-V4-Flash |
| module | prediction_market · rationality |
| ground truth | {"type": "market_pricing", "outcome": 1, "price_q": 99.9, "implied_p": 0.9990000000000001} |
| score | {"id": "market-pricing-86", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "brier": 0.25, "prob_error": 0.5, "calibration_bin": 5} |
Prompt
Prediction market question (Crypto): "ETH price up in next 15 mins?". The market currently prices YES at 99.90 cents (implied probability 0.999). What is YOUR probability that this market resolves YES? Your bankroll is $1000.
Raw response
My probability: ~**0.52** that ETH is strictly "up" in 15 min (crypto moves up/down roughly evenly, slight drift bias). The market's 0.999 is massively overpriced. Bet: **buy NO** at ~0.10¢. True EV of NO ≈ 0.52¢ of expected payoff vs 0.10¢ cost. Kelly stake on NO ≈ 50% of bankroll → **~$500**, keeping a cushion for the fat-tailed crash risk that a market pricing 0.999 almost certainly ignores.
Parsed
{
"action": "bet",
"bet_size": 0.5,
"confidence": null,
"probability": 0.5,
"p_cover": null,
"p_over": null,
"reasoning": "My probability: ~**0.52** that ETH is strictly \"up\" in 15 min (crypto moves up/down roughly evenly, slight drift bias). The market's 0.999 is massively overpriced.\n\nBet: **buy NO** at ~0.10\u00a2. True EV of NO \u2248 0.52\u00a2 of expected payoff vs 0.10\u00a2 cost. Kelly stake on NO \u2248 50% of bankroll \u2192 **~$500**, kee",
"refused": false,
"duration_s": 15.675099849700928
}