I've been playing around with the Kelly calculator for simultaneous wagers, but I can't seem to figure out how it's calculating expected growth.
Based on what this article presents (along with a basic understanding of the geometric mean) I've been trying to calculate the expected growth of 2 simultaneous wagers.
Assume a quarter Kelly stake on 2 wagers at +100 odds with a 55% chance of winning. The calculator says to bet 2.4450% on each, and the expected growth is 0.4397%.
When I try to calculate the expected growth by hand:
1.048899^0.3025 x 1.00^0.4950 x (1-0.048899)^0.2025 - 1
I obtain 0.4299% (I know the middle piece isn't necessary, I just included it for clarity).
I assume I'm messing up somewhere, so any thoughts would be great!
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