Kelly Criterion
f = (b·p − q) ÷ b
Kelly sizes each bet by your edge. Most bettors use half or quarter Kelly to keep swings smaller.
Questions about the kelly criterion
What is the Kelly criterion?
A formula for the share of your bankroll to stake: f = (b × p − q) ÷ b, where b is decimal odds − 1, p is your win probability and q is 1 − p.
Why use fractional Kelly?
Full Kelly assumes your probability estimate is exactly right, and its swings are large. Half or quarter Kelly gives up a little growth for much smaller drawdowns.
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