Sharps! Kelly Help

[FreeFall]

So I've finally decided to move away from flat betting to kelly.

I have my slow line for an NBA total at 183.5 -120
My Market is at 180 -105

for kelly I need
f* is the fraction of the current bankroll to wager;
b is the net odds received on the wager (that is, odds are usually quoted as "b to 1")
p is the probability of winning;
q is the probability of losing, which is 1 − p.
f* = bp-q / b

In the case above my b is -120 to 1.8333333:1. I then use b as = 1.83333333
my p is the probability of winning which is 61.17% which I got from RBS half point calculator when using 180 -105 and changing the odds to 183.5.
then q is 1-61.17 which is .3883

thus we have f* = ( (1.8333333 * .6117) - (.3883) ) / (1.8333333)
= .3998

that would mean I'd bet 39% of my bankroll on this? Where am I going wrong with my formating?

 

[reno cool]

figure out your edge and bet to win that amount

 

[Potato]

Wat r fair oddz @ 183.5 on teh h-p-c?

 

[reno cool]

you're saying you have an 11.9% edge at -120. would mean you risk 14.28% of bankroll for full kelly. that's my understanding

 

[FreeFall]

figure out your edge and bet to win that amount

well if I expect this to win 61% of the time from the RBS half calc then it would be .6117-(120/220) for a .066 6.6% bet on it? That seems high

you're saying you have an 11.9% edge at -120. would mean you risk 14.28% of bankroll for full kelly. that's my understanding

Can you write out how you got those numbers? Where did you find 11.9% endge?

Wat r fair oddz @ 183.5 on teh h-p-c?

I'm not sure if you're being serious of a smartass. Either way I don't really have much to help answer your question.

 

[reno cool]

61% X 1.83 =1.119 11.9% edge. that is high. you sure you actually have a 61% chance?

 

[MonkeyF0cker]

b = 0.83333333

That's your problem.

 

[MonkeyF0cker]

figure out your edge and bet to win that amount

Nevermind. Misread. :thumbsup:

 

[Potato]

 

[MonkeyF0cker]

LOL. When I do it with the Half Point Calc it says 7.94% edge with a 58.86% win rate (assuming its 180 -105/-105).

In any case, I wouldn't put much stake in that calculator. It only does push rates. It's not a distribution that allows you to move too far from the median with accuracy.

 

[Potato]

Potato did +105/-105 since he was never given the fair odds.

It's outdated since Ganchrow left the forum. Potato just uses Pinny dynamics.

 

[FreeFall]

b = 0.83333333

That's your problem.

Thank you! That made it 5% of my BR which makes more sense, but is rather high. I'm used to running 1-2.5%, do you guys use that as the to win amount or risk?

 

[FreeFall]

that isn't working in your browser. You can tell by the 0%s in the edge column.

 

[MonkeyF0cker]

The problem with using Pinny dropdowns is that you really can't use it for something like this - a 3.5 point differential.

 

[MonkeyF0cker]

that isn't working in your browser. You can tell by the 0%s in the edge column.

It's working. The 0%'s are because he used a no-vig line.

 

[MonkeyF0cker]

Thank you! That made it 5% of my BR which makes more sense, but is rather high. I'm used to running 1-2.5%, do you guys use that as the to win amount or risk?

Hmm. I get 14.574% at full Kelly with the numbers you posted...

 

[choo]

In any case, I wouldn't put much stake in that calculator. It only does push rates. It's not a distribution that allows you to move too far from the median with accuracy.

important stuff, imo.

 

[FreeFall]

Hmm. I get 14.574% at full Kelly with the numbers you posted...

yeah I was wrong I just re ran it in excel had my formula setup wrong. Still isn't that a rather high number to be risking on one play?