Swing
Study notes and tools, separate from the day-trading screener on /trade.
Kelly position sizer
The optimal bet fraction for a given edge, and what happens to it when your estimate of that edge is wrong.
55%
2.0 : 1
Full Kelly
32.5%
$16,250
Half Kelly
16.3%
$8,125
Quarter Kelly
8.1%
$4,063
Most practitioners size at half Kelly or less — full Kelly is only correct if your win-rate estimate is exactly right.
Growth rate vs. bet size
The peak is the optimal fraction. Past it, growth falls — that's the cliff.
If your win-rate estimate is off
Sized for a 55% win rate. Shows growth if the true rate turns out different — full Kelly vs half Kelly.
Binary win/loss model, full risked amount lost on a loss. Estimate your inputs from a large enough sample — small backtests overstate confidence.