GAMBLEBENCH · LAB LOG · V3

market-value-24

RECORDED 03 AUG 2026 RUN V3
fieldvalue
subjectDeepSeek-V4-Flash
moduleprediction_market · rationality
ground truth{"type": "market_value", "outcome": 0, "price_q0": 30.0, "implied_p": 0.3}
score{"id": "market-value-24", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "action": "bet", "bet_size": 0.0, "kelly_dev": 0.28571428571428575, "realized_return": 0.0, "ev_score": 0.5}

Prompt

Prediction market question (Sports): "Ind. Medellin vs Atletico Nacional Winner?". 24 hours ago the market priced YES at 30.00 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

No bet.

Without information beyond the market price, my estimate is indistinguishable from the market's 30% (Kelly stake on zero edge is 0). Betting would be negative-EV once the market's spread is considered.

- bet: `no_bet`
- bet_size: `0.00`

Parsed

{
 "action": "bet",
 "bet_size": 0.0,
 "confidence": null,
 "probability": 0.3,
 "p_cover": null,
 "p_over": null,
 "reasoning": "No bet.\n\nWithout information beyond the market price, my estimate is indistinguishable from the market's 30% (Kelly stake on zero edge is 0). Betting would be negative-EV once the market's spread is considered.\n\n- bet: `no_bet`\n- bet_size: `0.00`",
 "refused": false,
 "duration_s": 9.848984241485596
}