This math proves Gambling is pointless

[Rich Boy]

There are tons of people out there who want to "beat the book" and make money betting on sports, but lets look at the numbers...


Say you:

• Have a $10,000 bankroll
• Get -105 on all bets
• Can consistently pick 52% winners
• Bet according to Kelly Criterion
• Make 5 wagers per day

This means:

• You will wager $158 per game
• Profit $1.19 every time you wager (on average)
• After 1 year you will profit $2171 (1825 wagers)

Is it really worth it? Sweating out 1825 wagers for 2 grand?

And this is extreme cases, most people will not pick 52%. The probability of picking 52% or more after 1825 wagers is 4.5%

The probability of even profiting over 1825 bets is only 15%

These are the numbers, this is the truth.

[Emily_Haines]

Many players can pick better than 52%.

Plus we can bet different amounts.

Your math is flawed.

[MonkeyF0cker]

I'm not sure where you're getting that number from but that's not even what you would make at half Kelly. At full Kelly in your example, your expected growth would be $5603.31. If you hit 53% with all of your other numbers intact, your expected growth would be $101,159.12.

Also, if you're betting professionally, you're generally going to make well over 5 plays a day.

Is it still not worthwhile?

[Rich Boy]

Many players can pick better than 52%.

Do you have any proof to back this up?

[Nicky Santoro]

richie, what kinda post is that? 5 bets a day? what if you find 14 good bets a day with value? only lay -105?? what if you can get games at +106 at matchy, or 1 pt better than the consensus line at -110, i'd bet it...

richie, delete this thread.. i dont like it..

[Rich Boy]

I'm not sure where you're getting that number from but that's not even what you would make at half Kelly. At full Kelly in your example, your expected growth would be $5603.31. If you hit 53% with all of your other numbers intact, your expected growth would be $101,159.12.

Also, if you're betting professionally, you're generally going to make well over 5 plays a day.

Is it still not worthwhile?

Let me break down my math so you can see how I came up with the numbers.

prof=e^(p*ln(bankroll+bet*(d-1))+(1-p)*ln(bankroll-bet))-bankroll

This is the formula I used to calculate my expected profit per wager.

bet = bet size
p = probability of winning
d = odds of the wager

With a 52% chance of winning at 1.952 odds, your bet size according to full Kelly is $158 (with a $10,000 bankroll)

and the profit per wager is $1.19

[MonkeyF0cker]

Rich Boy,

Check the Kelly calculator in Betting Tools to calculate your expected growth for these types of hypotheticals.

[Rich Boy]

Im just trying to show that even if you manage to get an edge, it will be small at best.

In this example the edge is 1.5%, which doesn't result in much profit...

If anyone has some insight or anything to add, I would appreciate it.

[rick_213]

You don't want to insult the gambler. He is never wrong..hehehe

[james4512]

if i had a 10,000$ bankroll omg that would be the day. My big plays would be bread winners

[MonkeyF0cker]

Let me break down my math so you can see how I came up with the numbers.

prof=e^(p*ln(bankroll+bet*(d-1))+(1-p)*ln(bankroll-bet))-bankroll

This is the formula I used to calculate my expected profit per wager.

bet = bet size
p = probability of winning
d = odds of the wager

With a 52% chance of winning at 1.952 odds, your bet size according to full Kelly is $158 (with a $10,000 bankroll)

and the profit per wager is $1.19

You've merely calculated expected value. You need to calculate expected growth.

See this post from Ganch: http://forum.sbrforum.com/handicappe...on-part-i.html

[reno cool]

sounds like you're flat betting.

Monkey, how do you get 1000% growth with 53%. nevermind

[acw]

Interesting to see that many do pay attention to their expected advantages. I know many advantage gamblers that never really go forward, because they just cannot work out their edge.

[betplom]

[Justin7]

52% is fine. Raise your bankroll to $200k, make 10 plays a day...

[tacomax]

Do you have any proof to back this up?

Simplistically, you can think of it as a normal (bell curve) distribution. The mean winning % is 50. One one end of the scale, you get the really bad bettors who can't resist the Yankees or the Lakers every day (I mean, how could that lose?) and hit 46%. In the middle you've got the people who make randoms picks and hit for the mean. And then you've got the people who actually analyze the lines and place value bets - they hit 54%. It's that easy. Knowing how to do it is difficult. Understanding how they theoretically could do it is not difficult.

[jjgold]

Stop making things complicated

watch and study Nicky

follow line movements at multiple books

have 7 top outs/stores

[G's pks]

Rich boy...not all of us overbet.... Not everyone an action junkie...