How it works
Six cards.
We publish when the sim is 80% or higher and the price is not heavy juice. Otherwise we sit. Sit is the product. The rest of the paper is one click down.
1. Batter vs pitcher
Each PA is a multinomial: strikeout, walk, HBP, single, double, triple, home run, or out. Probabilities are log5 combinations of batter rates and pitcher K/9, BB/9, HR/9, then shifted for platoon (same-hand Ks up, extra-base hits down). Known arsenals — Rodón slider, Gausman splitter, Sánchez sinker/change — weight the matchup toward the pitch types that batter actually sees.
2. Decay
Starters are pulled on pitch count, times-through, and blowout rules. After the hook, the bullpen inherits with a fatigue score from recent run environment. A velocity/spin flag (ERA spike vs season) taxes K rate and inflates HR and walk rates on the way out.
3. Weather physics
Stadium feed temp, wind, and condition go into density altitude. Lower air density, hotter air, and wind out to center field raise the HR multiplier; a 15 mph blow-out at Wrigley is not a 15 mph blow-out at Oracle. Humidor parks (Coors, Chase, Globe Life) cut the coefficient of restitution. Domes ignore wind.
4. The umpire
Home-plate assignment comes off the MLB officials feed. Wide zones add Ks and kill walks (Under lean). Tight zones do the opposite (Over lean). The shadow zone is the highest-leverage inch in the sport and books are slow to fully price it.
5. True vs the window
Fair odds are the no-vig inversion of simulation frequencies. DraftKings, FanDuel, BetMGM, bet365, Fanatics, and Caesars print live. We never invent a second book by shading DraftKings. Edge is true probability minus market implied. Green cells on Markets are +EV. We bet the difference, not the narrative.
6. The 80% desk rule
We publish when the sim is 80% or higher and the price is not heavy juice. Otherwise we sit. Posted moneyline, posted total, and run line are checked first. 80.0 is a lock unless the price is heavy juice. If the posted Under is not the number on the card (8.0 or 8.5 when that is the total), we sit. We do not lock an 11.5 alternate as an official ticket. Official tickets lock one hour before first pitch, then freeze. They are graded against the final and cannot be edited. Every ticket is saved with the sim snapshot at lock (mean total, true win, weather, umpire, starters) and kept on the ledger.
Full methodology
7. 65% desk book
If a side is at least 65% but under the 80% floor, it is written into a real book: pick, game, posted %, fair and posted price, close (or “no posted book (alternate)”), grade, units. Stake is 1u default, 0.5u when the fair or posted price is −200 or shorter. The book is append-only — oldest stays, misses stay, running units walk the list. It is never stamped as an official ticket and never enters the 80% win–loss record.
8. Alerts
Official: one LOCK when a ticket freezes, one SIT per sport-date after 7pm ET. Desk pass: one digest per sport per slate, not one mail per play. Never a 65% lean on the official list.
9. Stake
Official tickets and the 65% book. 1u default. 0.5u when the fair or posted price is −200 or shorter. No bankroll dashboard — the desk sits, it does not size a season for you.
10. The public board and the desk pass
Logged out: tonight’s LOCK or SIT, the official ticket (side, lock, best number, units, hash, freeze), W–L, sit count, CSV, one Markets True demo. Signup is free. 65% rows, full Markets True, lab, snapshots, extra alerts stay on the desk pass after Stripe confirms that email paid $39/mo or $299/yr. Official 80% is not paywalled.
11. Dual engine
The public 80% ledger sits when the market is priced. That record is the product. The desk pass is a separate 65% book. It never writes the official ledger.
12. Invisible context
Travel-fatigue scores road clubs on rest, extras, time-zone shift, and early getaways. Umpire cards now shift in high leverage (RISP, two outs, late innings) and carry a catcher-framing proxy. Weather uses density altitude plus humidity and barometric pressure so Coors air is not Tropicana air even at the same wind reading. Carry is reported in inches.
13. Derivative markets
NRFI, first-five moneyline and total, and first-15-pitch strikeouts are priced off the same plate-appearance sim. Books often shade those off a static template. Those markets live on the desk, not on the official 80% book.
14. The lab
The lab lets you shift wind and humidity and re-run worlds. Locked 80% tickets do not move. Desk 65% is not official and never writes the 80% ledger.
Live inputs: MLB Stats API, live books (DK / FD / MGM / bet365 / Fanatics / Caesars). Research only. Not a sportsbook. 21+. Operated by Jay.