Learn/kelly
What is Kelly sizing?
How much of the roll
Kelly says: stake in proportion to your edge. Full Kelly is a loud roommate. We default to a quarter of it.
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slice
4% edge at 2.20 — don’t send the whole pie
Full Kelly ≈ 3.3% of the roll.
We use a quarter: 0.8%. Loud enough to matter, quiet enough to survive a red week.
The formula is edge divided by (decimal odds minus one). A 4% edge at 2.20 is a small slice, not a swing at the fences.
Full Kelly maximises growth on paper and maximises heartburn in a real book with limits and losing weeks. A quarter is how we size the Value board.
Locks are not Kelly. They are a split. The Arb sizer already dutch-books the roll so both doors pay the same.
takeawayQuarter-Kelly on Value. Use the sizer on arbs and middles. Never invent two different totals in your head for a lock.