GAMBLEBENCH · LAB LOG · V3

market-value-12

RECORDED 03 AUG 2026 RUN V3
fieldvalue
subjectNemotron-3-Ultra
moduleprediction_market · rationality
ground truth{"type": "market_value", "outcome": 1, "price_q0": 43.0, "implied_p": 0.43}
score{"id": "market-value-12", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "action": "bet", "bet_size": 0.0, "kelly_dev": 0.12280701754385964, "realized_return": 0.0, "ev_score": 0.5}

Prompt

Prediction market question (Sports): "New York Y wins by over 1.5 runs?". 24 hours ago the market priced YES at 43.00 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 don't have enough information to form a probability estimate. "New York Y" is ambiguous (Yankees? vs whom?), and I lack team stats, pitching matchups, injuries, weather, etc.

**Framework if you have an estimate `p`:**

- Market implied probability: 43% (0.43)
- Kelly fraction: `f = (p - 0.43) / (1 - 0.43) = (p - 0.43) / 0.57`
- Bet if `p > 0.43` (positive edge)
- Fractional Kelly (e.g., 0.5×) recommended for safety

**Example:** If you estimate `p = 0.55`, full Kelly = `(0.55-0.43)/0.57 ≈ 21%` of bankroll ($210). Half-Kelly = ~$105.

Without a grounded `p > 0.43`, **optimal bet = $0**.

Parsed

{
 "action": "bet",
 "bet_size": null,
 "confidence": null,
 "probability": 0.43,
 "p_cover": null,
 "p_over": null,
 "reasoning": "I don't have enough information to form a probability estimate. \"New York Y\" is ambiguous (Yankees? vs whom?), and I lack team stats, pitching matchups, injuries, weather, etc.\n\n**Framework if you have an estimate `p`:**\n\n- Market implied probability: 43% (0.43)\n- Kelly fraction: `f = (p - 0.43) / (",
 "refused": false,
 "duration_s": 27.045483589172363
}