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Chancer
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Joined: July 27th, 2001, 10:16 am

Sure fire winner?

July 27th, 2001, 10:34 am

I am new to all this... but I wonder if...Let us say that in an eight horse race there could very occasionally arise, due to the semi-chaotic way the odds are shaped, an opportunity for a spread of bets on each horse that would guarantee either a return, or at the very least the ability to break even. Could a software app be written that could scan online betting site odds and alert when a race is 'HOT' and that would calculate the spread of bets that needed to be placed?What do you think?
 
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Paul
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Joined: July 20th, 2001, 3:28 pm

Sure fire winner?

July 27th, 2001, 11:38 am

Just like in pricing derivatives it's not the actual probabilities that matter when the odds are set. Depending on how the betting goes, the odds will be set so that the House/Bookie cannot lose. For example, in a soccer match between England and Germany the Germans are more likely to win, but the patriotic English will bet more heavily on England (presumably). The odds given by the bookies will reflect this betting and make it look like England is more likely to win. Of course, in Germany the situation is reversed. The best bet would be on Germany, but placed in England, and one on England placed in Germany! In practice bookies in one country would lay off their bets on bookies in other countries so all bookies have roughly the same odds. Otherwise there would be straightforward arbitrage opportunities.In practice it's unlikely for there to be a sure-fire bet (unless the bookie has made a mistake, the race is fixed, or you can find two or more bookies that aren't directly or indirectly laying off their bets on each other). But you can win, on average. By exploiting the difference between the real probability of a horse winning and the odds you can get. (There are differences between real odds and what you get paid in all casino games, but it's only in Blackjack that this can be exploited.) Give me a few minutes to write a simple Excel spreadsheet to illustrate this, and we'll upload it.P
 
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Aaron
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Joined: July 23rd, 2001, 3:46 pm

Sure fire winner?

August 1st, 2001, 8:42 pm

I spent many hours of my childhood on this question. I never attended a horse race, nor did I have any interest in horses. But the numbers in the newspaper, later the racing form, were too tantalizing to ignore.Like most people, I discovered it is relatively easy to make up the track percentage (10 percent in those reasonably honest days, 15 percent to 25 percent as the government has taken over the gambling business, despite the lower payout ratios the government activities are far less profitable than the old-fashioned ones they replaced). Bet on the second favorite to win (amateurs bet either the favorite or a long-shot). Bet on the favorite and second favorite in the exacta (when amateurs bet exactas they want high payouts, picking two horses for a 3 to 1 payout is unappealing). Unfortunately, there were enough professionals around to arbitrage away any activities that actually made a profit.Some people claim that with careful study of racing form and odds it is possible to eke out a small edge. But I suspect that errors, costs and taxes eat all of that up.One profitable system which has always appealed to me is the one where you place large bets at a small race at a small track; at the track itself. Then you place much larger bets with bookies who pay off at track odds (a vanishing breed, unfortunately).The results are similar with most forms of public betting. There are bets that are clearly bad because they are the ones that people like to make. It is easy to find unpopular bets that make up the house or bookie or government edge. But the professionals are sharp enough not to allow anyone to actually make money.
 
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Paul
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Sure fire winner?

August 2nd, 2001, 5:05 pm

I wrote the spreadsheet example straight after my last message, but forgot to upload it...and I'm now on my hols so it will have to wait until I get back...don't lose any money on the horses until then, Chancer!P
 
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Paul
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Joined: July 20th, 2001, 3:28 pm

Sure fire winner?

August 11th, 2001, 8:18 am

I've uploaded a very simple spreadsheet for calculating wager size based on the odds set by the bookie and the real probabilities as you believe them to be. Please comment on the spreadsheet, it was rather rushed so is probably full of errors. There's also an exercise at the end for the enthusiastic gamblers out there!P
Attachments
Horses1.zip
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Chancer
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Joined: July 27th, 2001, 10:16 am

Sure fire winner?

August 13th, 2001, 11:59 am

Thanks Paul,I will experiment... (without using real cash, well just yet anyway...)Forgive me if I appear rather 'green' but can you offer a method to aid coming up with reasonably accurate propabilities...?Is it using form, going, jockey etc to balance up against the bookie's odds?Chancer
 
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Paul
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Joined: July 20th, 2001, 3:28 pm

Sure fire winner?

August 13th, 2001, 12:06 pm

I haven't a clue...but I know a man who has. I'll try and get him onto the forum.P
 
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Chancer
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Joined: July 27th, 2001, 10:16 am

Sure fire winner?

August 13th, 2001, 3:30 pm

Aaron stated...Bet on the second favorite to win (amateurs bet either the favorite or a long-shot). >>So as an experiment today, whilst waiting on some help with Paul's excel file, I placed 14 single £1.00 bets to win on the second favourites in each of 14 horse races this afternoon in the UK.Total Bet £14.00 (No tax payable as Internet bet was placed)Southwell returned three winners from six races at odds of 7/2, 7/2 and 11/4Folkstone returned two winners from eight races at odds of 9/2 and 5/1Total Profit £9.25 Thanks Aaron.... now if only I had bet £1,000 on each....
 
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Paul
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Joined: July 20th, 2001, 3:28 pm

Sure fire winner?

August 14th, 2001, 5:39 pm

What internet gambling site did you use/do you recommend?P