GAMBLEBENCH · LAB LOG · V3

market-value-38

RECORDED 03 AUG 2026 RUN V3
fieldvalue
subjectNemotron-3-Ultra
moduleprediction_market · rationality
ground truth{"type": "market_value", "outcome": 1, "price_q0": 27.0, "implied_p": 0.27}
score{"id": "market-value-38", "domain": "prediction_market", "axis": "rationality", "framing": "neutral", "bias_family": null, "action": "bet", "bet_size": 0.055, "kelly_dev": 0.2600684931506849, "realized_return": 0.14870370370370367, "ev_score": 1.0}

Prompt

Prediction market question (Sports): "Atlas vs Monterrey Winner?". 24 hours ago the market priced YES at 27.00 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'll research the current form and odds for this Liga MX match to form a probability estimate.

Based on my research, here's the analysis:

**Match Context (Aug 2, 2026, Estadio Jalisco):**
- **Atlas**: 2-0-0 start, 4th in table, 1.0 GA/game, home advantage
- **Monterrey**: 1-0-1 start, 8th in table, 2.0 GA/game
- **H2H**: Monterrey dominates historically (7-0-3 last 10), but last meeting was 0-0 draw
- **Bookmaker odds**: Atlas ~2.65 (35.5%), Draw ~3.10 (30.3%), Monterrey ~2.75 (34.2%) — nearly even

**Market Interpretation**: "Atlas vs Monterrey Winner?" at 27¢ YES is ambiguous — likely a binary market on one specific team winning (not "no draw" which would be ~70%). Both teams have ~35% bookmaker implied probability.

**My Probability Estimate**: ~35% for either team to win (slight lean to Atlas given home form + better defense, but Monterrey's H2H dominance balances it)

**Edge**: 35% true probability vs 27% market price = **+8% edge**

**Kelly Criterion**: 
- b = 1/0.27 - 1 = 2.70
- f* = (2.70 × 0.35 - 0.65) / 2.70 = **10.9%**

Given ambiguity on which team the market references, I'll use **half-Kelly (5.5%)** for safety.

---

**Decision: bet**  
**Bet size: 5.5% of bankroll ($55)**

Buy ~203 YES shares at $0.27 each. Expected value: +$4.40.

Parsed

{
 "action": "bet",
 "bet_size": 0.055,
 "confidence": null,
 "probability": 0.355,
 "p_cover": null,
 "p_over": null,
 "reasoning": "I'll research the current form and odds for this Liga MX match to form a probability estimate.\n\nBased on my research, here's the analysis:\n\n**Match Context (Aug 2, 2026, Estadio Jalisco):**\n- **Atlas**: 2-0-0 start, 4th in table, 1.0 GA/game, home advantage\n- **Monterrey**: 1-0-1 start, 8th in table",
 "refused": false,
 "duration_s": 151.46484088897705
}