Question about Kelly and calculating your edge

[Stocks]

If someone has a 55% winning percentage at average odds of -107 and they want to bet Atlanta Braves +150.

What is your overall edge?

How do you find your win probability for that game?

Is your overall edge 3.3% and if so would your win probability for a +150 game be 43.3%

or

Is your overall edge is 3.3% and your win probability for a +150 game would be 41.32%

Thanks

[Romanov]

Past winning percentage has nothing to do with edge. If the individual game has a 55% probability to go one way and you can get it at -107:

.55/(107/207) - 1 = edge = 6.4%

Or if you somehow had a game with 55% prob and odds of +150:

.55/(100/250) - 1 = edge = 37.5%

[Stocks]

Are you sure past performance has nothing to do with edge? If you bet 5000 baseball games and hit 55% at -107 wouldn't it be safe to say you have a 3.3% edge in baseball?

55% at -107 odds = 3.3% edge (overall edge)

Atlanta +150 = 40% (breakeven point)

40% x 3.3% = 41.32% (win probabilty)

1.50 x 41.32% = 0.6198 (betting odds x win probabilty)

1 - .4132 = 58.68% (losing probabilty)

0.6198 - .05868 = 0.033 (betting odds x win prob - lose prob)

0.033 / 1.50 = 0.022 (number above / betting odds)

Answer 2.2%

That was the same answer I got on the kelly calc

[Stocks]

Ok I see how you got the 6.4% but couldn't we still say we would have an average 6.4% edge in each game?

[Romanov]

Ok I see how you got the 6.4% but couldn't we still say we would have an average 6.4% edge in each game?

each game is an independent event (kinda) so no.

[FourLengthsClear]

Using a historical record as a basis for establishing an edge for future matches is not recommended.

You can say that your edge to date has been 6.4% (+/- the effects of variance).