GAMBLEBENCH · QUOTE TERMINAL · V3
market-value-0
RECORDED 03 AUG 2026 RUN V3
| field | value |
|---|---|
| instrument | DeepSeek-V4-Flash |
| module | prediction_market · rationality |
| ground truth | {"type": "market_value", "outcome": 1, "price_q0": 58.0, "implied_p": 0.58} |
| score | {"id": "market-value-0", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "action": "bet", "bet_size": 0.1, "kelly_dev": 0.1, "realized_return": 0.0724137931034483, "ev_score": 1.0} |
Prompt
Prediction market question (Mentions): "What will the announcers say during Cub Swanson vs Nate Landwehr UFC Fight?". 24 hours ago the market priced YES at 58.00 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
I have no reliable information about these teams, so my honest probability estimate is ~50% (maximally uncertain), well below the 71¢ market price. - **Betting YES is negative EV** (my 50¢ EV per share < 71¢ cost) — so *not* buying YES. - If buying NO is allowed (price 29¢, pays $1 if NO): EV = 0.50 − 0.29 = +21¢/share. Kelly fraction ≈ 0.30, but given my estimate is essentially an ignorance prior with high variance, I'd de-risk it. **Decision: bet on NO, bet_size ≈ 0.10–0.15 of bankroll** ($100–$150 on NO shares). **If the market only allows buying YES: no_bet.**
Parsed
{
"action": "bet",
"bet_size": 0.1,
"confidence": null,
"probability": 0.5,
"p_cover": null,
"p_over": null,
"reasoning": "I have no reliable information about these teams, so my honest probability estimate is ~50% (maximally uncertain), well below the 71\u00a2 market price.\n\n- **Betting YES is negative EV** (my 50\u00a2 EV per share < 71\u00a2 cost) \u2014 so *not* buying YES.\n- If buying NO is allowed (price 29\u00a2, pays $1 if NO): EV = 0.5",
"refused": false,
"duration_s": 19.65602684020996
}