Boston Red Sox vs. Toronto Blue Jays: 1st 5 Innings O/U 5.5
Crossbook compares what two exchanges, Polymarket and Kalshi, charge for the same event, and publishes a permanent scored record of its own forecasts under published rules.
Tracked on one venue, with Crossbook's own call on the record.
This market has settled and is no longer listed, so there is no current price to show. What Crossbook called, and when, is below.
Crossbook forecast
- 38.0%against a market price of 34.5% at the timeNO
Logged 13 Aug 2026, 14:56 UTC · Brier 0.1444
- Reference class is league-average F5 scoring: ~50-55% of a ~9-run game occurs in innings 1-5, giving a mean near 4.8 and P(6+ runs) around 40-44% with typical run-distribution overdispersion; that is my independent anchor absent game-specific data.
- Signal I do NOT have: starting pitchers, lineups, umpire, and Toronto weather/roof status for this specific date; these routinely swing F5 over probability by 10-15 points, so my inside-view adjustment is mostly a reversion toward the informed market rather than a true independent read.
- The market's 34.5% is below my naive ~43% anchor; the plausible cause is known same-day information (e.g., a strong pitching matchup or run-suppressing conditions) that I cannot observe, so I blend ~60/40 toward the market, landing near 38% rather than fading it to base rate.
What would change it: Confirmed starting-pitcher matchup and weather/roof report: a bullpen game or hitter-friendly wind would push this toward 48%+, while two frontline starters plus cold/wind-in conditions would justify the low-30s or lower.
Settlement source
Context
This market has settled. The page is kept as a record of what the market said while the question was open, and of what Crossbook called.
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