[Mahowny82]

Hello all,

I'm trying to calculate the edge I had in my past betting sample but I get stuck.

I'm just going to throw some numbers here:

Made bets: 1490
Winning bets: 550
Average winning odds: 3.39.
Commision: 5% of profit on winning bets....

What's the correct way to calculate my past edge?

Also with these numbers how much percentage of my bankroll should I bet to make my bankroll grow optimally? (assuming edge stays the same etc)

Thanks

[allin1]

550 / 1490 = 0.369 so almost 37% win rate
if 5% commision is only on profit, then the real average winning odds are 3.27 <1+(3.39-1)*(1-0.05)>
implied probability (not including juice) for 3.27 is 30.5% <1 / 3.27>

if you have a 37% win rate for implied probability of 30.5% then you could say you have a 6% edge but including juice it would probably be around 4%.

I am not sure if this is accurate. Some professionals will definitely do this differently.

for your last question I recommend

[Mahowny82]

Thanks for your response, it was very helpfull.

Not sure what you mean by juice though. You already accounted for the 5% commission?

I will take a look at that video tomorrow!

Thanks

[allin1]

if you have 3 way odds: 2.6 , 3.2, 2.9

the implied probabilities without juice are

1 / 2.6 = 0.3846 ---> 38.46%
1 / 3.2 = 0.3125 ---> 31.25%
1 / 2.9 = 0.3448 ---> 34.48%

If you add those up you have 1.0419 or 104.19%. That's the juice.

In order to get the implied probability considering the juice you have to divide the implied probs to 1.0419

0.3846 / 1.0419 = 0.3691 ---> 36.91%
0.3125 / 1.0419 = 0.3000 ---> 30.00%
0.3448 / 1.0419 = 0.3309 ---> 33.09%

36.91% + 30.00% +33.09% = 100%

[Mahowny82]

Aha I understand what you mean now about the juice... thanks.

I watched the video and I think I understand most of it now. Lets see if I'm doing it right.

I bet on a exchange and I pay 5% commission on winning bets. I mostly bet on horse racing.

If I want to use Kelly and I THINK

I've got an 3% edge and the odds I can bet at are 3.39. How much of my bankroll should I bet?

33.58-3.39 - (1-0.3358) / 3.39 = 8.71%

Am I doing it right?

[allin1]

the real odds for 3.39 - 5% commision are 3.27 if you are paying 5% of your profit.

1 / 3.27 = 0.305 that's 30.5% implied probability without counting juice

considering the juice I will presume the actual implied probability is somewhere around 32.5% but you can calculate it with the method described previously

add to that your 3% edge and you will have 35.5% and you will use in formula 0.355

kelly:

[ 0.355 x 2.27 - (1-0.355) ] / 2.27 = 0.07

so you should bet a maximum of 7% of your bankroll

considering that these calculations are not completly accurate you can use half kelly and bet just 3.5% or something near to that.

it depends what kind of odds you bet if from 1400 bets you have made 800 at odds around 2, 200 at odds around 3.7 and 400 at odds around 6 then things change and I wouldn't even know how to estimate your edge.