GAMBLEBENCH · LAB LOG · V3

market-pricing-57

RECORDED 03 AUG 2026 RUN V3
fieldvalue
subjectBig-Pickle
moduleprediction_market · rationality
ground truth{"type": "market_pricing", "outcome": 0, "price_q": 71.0, "implied_p": 0.71}
score{"id": "market-pricing-57", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "brier": 0.09, "prob_error": 0.3, "calibration_bin": 3}

Prompt

Prediction market question (Sports): "Valero Texas Open: Will J.T. Poston finish top 20?". The market currently prices YES at 71.00 cents (implied probability 0.710). What is YOUR probability that this market resolves YES? Your bankroll is $1000. 

Raw response

My probability that J.T. Poston finishes top 20 at the Valero Texas Open: **~0.35**.

A mid-tier (approx. top-50 world) player like Poston runs a career top-20 rate around 28-30% in full fields; the pre-Masters field at this event is slightly weak, bumping him to ~33-38%. That is far below the market's 0.71, so YES looks overpriced.

With $1000: I'd sell YES (buy NO at 29¢). Quarter-Kelly stake ≈ **$125** on NO (edge ≈ 0.36; implied NO odds ~3.45x).

Parsed

{
 "action": "bet",
 "bet_size": null,
 "confidence": null,
 "probability": 0.3,
 "p_cover": null,
 "p_over": null,
 "reasoning": "My probability that J.T. Poston finishes top 20 at the Valero Texas Open: **~0.35**.\n\nA mid-tier (approx. top-50 world) player like Poston runs a career top-20 rate around 28-30% in full fields; the pre-Masters field at this event is slightly weak, bumping him to ~33-38%. That is far below the marke",
 "refused": false,
 "duration_s": 32.913878202438354
}