GAMBLEBENCH · LAB LOG · V3
market-value-29
RECORDED 03 AUG 2026 RUN V3
| field | value |
|---|---|
| subject | Big-Pickle |
| module | prediction_market · rationality |
| ground truth | {"type": "market_value", "outcome": 0, "price_q0": 45.0, "implied_p": 0.45} |
| score | {"id": "market-value-29", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "action": "bet", "bet_size": 0.0, "kelly_dev": 0.09090909090909088, "realized_return": 0.0, "ev_score": 0.5} |
Prompt
Prediction market question (Sports): "Houston wins by over 1.5 runs?". 24 hours ago the market priced YES at 45.00 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, bet_size = 0. I have no edge here: without team-specific information, my best estimate of P(Houston wins by >1.5) equals the market's implied 45%. With p = 0.45 and payoff b = 0.55/0.45, Kelly edge is (0.55 − 0.55) = 0, so no bet is optimal.
Parsed
{
"action": "bet",
"bet_size": 0.0,
"confidence": null,
"probability": 0.45,
"p_cover": null,
"p_over": null,
"reasoning": "no_bet, bet_size = 0.\n\nI have no edge here: without team-specific information, my best estimate of P(Houston wins by >1.5) equals the market's implied 45%. With p = 0.45 and payoff b = 0.55/0.45, Kelly edge is (0.55 \u2212 0.55) = 0, so no bet is optimal.",
"refused": false,
"duration_s": 10.878148317337036
}