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Author Topic: Betting probability of a win????
Mikebyrne
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Icon 1 posted August 14, 2009 09:01      Profile for Mikebyrne     Send New Private Message       Edit/Delete Post   Reply With Quote 
When I look at the odds for a football match they are presented as (for example):

Liverpool: 5/6

Draw: 5/2

Spurs: 10/3

How could I work out the % chances of a win based on the odds??

ie Liverpool 70%
Draw 20%
Spurs 10%

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TheMoMan
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Icon 1 posted August 14, 2009 09:12      Profile for TheMoMan         Edit/Delete Post   Reply With Quote 
_____________________Mikebyrne ________________

Liverpool: 5/6 5/6= .83666%


Draw: 5/2 5/2= 250%

Spurs: 10/3 10/3= 333%

____ However this is the betting odds, and sometimes the players don't read the betting papers. They just go out and play their game, and the results are paid by the bookies.

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Mikebyrne
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Icon 1 posted August 14, 2009 09:27      Profile for Mikebyrne     Send New Private Message       Edit/Delete Post   Reply With Quote 
TELL ME ABOUT IT MO!!!

I understand that 5/6 represnts a payout of 0.83 etc but I was jst wondering how I could compare all three odds and turn them into percentages ie 70% - 15% -15%

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Stereo

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Icon 1 posted August 14, 2009 09:51      Profile for Stereo     Send New Private Message       Edit/Delete Post   Reply With Quote 
I'd go for lower common denominator. First reverse the odds, since the more chance of an outcome, the lower the payout, then get them on equat "footing":

Liverpool: 6/5 -> 12/10
Draw: 2/5 -> 4/10
Spurs: 3/10
Total: 19/10

Of course the total is greater than one, but that's the reverse payout. Now, you take each occurence on the total. (Results rounded to the unit.)

Liverpool: 12/19 -> 63%
Draw: 4/19 -> 21%
Spurs: 3/19 -> 16%

Again, that's how *I* think it's best done, but I could be wrong. I haven't touched that for years.

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The Famous Druid

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Icon 1 posted August 14, 2009 16:30      Profile for The Famous Druid     Send New Private Message       Edit/Delete Post   Reply With Quote 
quote:
Originally posted by Mikebyrne:
How could I work out the % chances of a win based on the odds??

You can't.

The odds quoted are the prices bookies offer, in their effort to maximize their own profit. It's a balancing act between offering 'good odds' (to entice mugs to bet) and 'bad odds' (to reduce their payout after the game). The probability of the team winning is a relatively minor factor in the bookies calculations, it's more about punter psychology.

For example, Long-shot bias is a fairly well-known phenomenon in the gambling biz. In plain English, long-shot bias says punters are idiots, they'd rather bet on the long-shot that pays 20:1 than the 'sure thing' at 5:4, even though the probability of the long-shot winning is way less than 5%.

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If you watch 'The History Of NASA' backwards, it's about a space agency that has no manned spaceflight capability, then does low-orbit flights, then lands on the Moon.

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Mikebyrne
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Icon 1 posted August 14, 2009 16:52      Profile for Mikebyrne     Send New Private Message       Edit/Delete Post   Reply With Quote 
I've been using the formula (1-N/(N+M)*100 to get my percentages based on the odds.

Therefore

Team A at 2/7 = 78%

Draw 5/1 = 18%

Team B 18/1 = 5%

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littlefish
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Icon 1 posted August 14, 2009 23:33      Profile for littlefish   Author's Homepage     Send New Private Message       Edit/Delete Post   Reply With Quote 
I hope you realise that this is not a realistic view of the world.

Firstly, the probability of the actual outcome must be higher than the odds or the bookie makes no money. Bookies make lots of money.

Secondly, there is no way of predicting the future. Bookmakers do not know what the odds are, they take a conservative punt at it, but they change their odds according to what people bet on. If too many people are betting on one outcome, the bookie will decide that he is being too generous and lessen the odds. Basically, the odds are set by the hive mind.

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Mr. Geek 2U
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Icon 1 posted August 16, 2009 16:43      Profile for Mr. Geek 2U     Send New Private Message       Edit/Delete Post   Reply With Quote 
Mo-Man,

You seem pretty good with those numbers.

I live in Michigan and I am wondering what are the odds that the Detroit Lions will win a game this year?

THATS Mr. Geek 2U!

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My friends call me Skippy

Posts: 260 | From: Kalamazoo | Registered: Aug 2009  |  IP: Logged


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