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Beating the bookies – how the online sports betting market is rigged

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Re: Beating the bookies – how the online sports betting market is rigged

#131

Post by mateo411 »

DSMan195276 wrote: post #78
darepublic wrote: post #62

Earlier quoted context omitted.

I guess you could always count from the sidelines and bet only in advantage spots. Not very practical I suppose but card counting in general seems pretty implausible these days

One strategy I know of is to have multiple people. One person sits at the table and always bets low, the other always bets high but only sits down if the person at the table signals to them that the odds are good (They can be off doing other stuff while the low-better is doing the counting, so they're not just standing around waiting). You're still right though, the odds aren't that great and once they get a hint you…

That's what the MIT blackjack team did in the 90s.

Re: Beating the bookies – how the online sports betting market is rigged

#132

Post by phillc73 »

andr3w321 wrote: post #104
LittlePeter wrote: post #100

Earlier quoted context omitted.

How would I go about contacting you?

Contact info is in profile but andr3w321 at gmail

People say their contact details are in their profile, but I never see contact details in any profile I view. Am I missing something?

Re: Beating the bookies – how the online sports betting market is rigged

#133

Post by phillc73 »

eric_h wrote: post #108
phillc73 wrote: post #32

Earlier quoted context omitted.

Betfair merged with Paddy Power, not Ladbrokes. They probably stopped offering their service in Canada due to unclear licensing and operating regulations for their Exchange product. It has happened in a number of other jurisdictions too. What you need is a good friend or relative in the UK or Ireland, and a VPN. However there are now other exchange betting options, with at least some degree of liquidity - Betdaq, Sma…

Minor nitpick re: horse racing: it's "totalisator" (usually abbreviated as "tote") and refers to the machine that keeps track of the pools and odds, and the term for the betting pool type is "parimutuel". Fun fact: totalisators were originally mechanical computers that were used to price betting pools around the turn of the 20th century ( http://www.computerhistory.org/atchm/racetrack-betting-mecha... ).

Thanks for the correction. I put that, and other spelling errors in that post, down to fat fingers on a mobile keyboard.

Re: Beating the bookies – how the online sports betting market is rigged

#134

Post by the_cat_kittles »

chillydawg wrote: post #101
the_cat_kittles wrote: post #92

Earlier quoted context omitted.

im actually curious how accurate the lines they show are, vs if you used their api. do you know? theres a lot of noise in them as far as i can tell- just wondering if its real or if they are jiggling the numbers around to make it look more appealing.

Site Vs API are identical. There may be some extra latency (order of milliseconds) on the site due to render time etc but they both use the same underlying data source.

interesting. have you used both? just curious how you know

Re: Beating the bookies – how the online sports betting market is rigged

#135

Post by the_cat_kittles »

phillc73 wrote: post #96
the_cat_kittles wrote: post #92

Earlier quoted context omitted.

im actually curious how accurate the lines they show are, vs if you used their api. do you know? theres a lot of noise in them as far as i can tell- just wondering if its real or if they are jiggling the numbers around to make it look more appealing.

Do you mean the Betfair lines? I think their market is pretty accurate. More so than many traditional bookmakers, although a lot of them use Betfair to make their own markets now, so there's very little chance of arbitrage between them. I've written an R library for the Betfair API[1], which I use every day to retrieve prices. https://www.github.com/phillc73/abettor

sorry i meant accurate in terms of what they show on the site vs what you can actually get when you try to trade. someone else answered that they are indeed accurate- has that been your experience?

Re: Beating the bookies – how the online sports betting market is rigged

#136

Post by PaulRobinson »

watoc wrote: post #126
PaulRobinson wrote: post #122

A bookmaker's tissue prices (the initial market prices they offer up), are not intended to be a measure of probability. They are meant to be a measure of expected Weight of Money (WoM). A bookmaker's job is not to accurately reflect odds of occurrence, but to ensure a balanced book of liabilities. There are many books covering this going back hundreds of years and is the principle discovery of those who gathered at T…

Interesting. You say: "The bookmakers don't care - you've helping get turnover up, and they know increasing turnover through the market is the best way to get balanced liabilities." And then: "1. Bookmakers will eventually end up closing their accounts, because winners are never welcome long-term." Is there any rational behind bookmakers not welcoming long-term winners? It seems like a bookie is very similar to a mar…

Over the short-term people adding WoM and bringing the book into line with other bookmakers is welcome, because it means the market is becoming more efficient.

At the micro level then, turnover is welcome. But as the old adage goes "turnover is vanity, profit is sanity"

At the macro level somebody has to say "how do we maximise profits or at least minimise losses?" and picking off accounts that are costing you money is an easy step to take.

The ideal client for a bookmaker is an idiot with a strong view. They don't want people who will consistently win, because it's taking up WoM for other customers who could be invited with those more generous odds and who _don't_ consistently win.

Re: Beating the bookies – how the online sports betting market is rigged

#137

Post by greggarious »

Personally I've come to find poker is the only reliable way to "beat the house". But that's because you're not beating the house, but other players - the house gets their rake.

If you play a tight-aggressive game in venues the pros avoid (anyplace with less than $2/hour comps in Vegas) you can do decently. Not get rich, but make a few hundred in an afternoon.

Re: Beating the bookies – how the online sports betting market is rigged

#138

Post by solatic »

danmaz74 wrote: post #110
solatic wrote: post #105

Earlier quoted context omitted.

Casino licenses are contingent upon offering a fair game at stated odds. The odds are allowed to benefit the house, of course, since that's how running a casino becomes a sustainable, profitable enterprise, but the stated odds cannot be dynamically changed in the middle of the game to benefit the house. Published blackjack odds depend on "dumb" reshuffles. If the house is "smartly" reshuffling the deck to reduce hous…

Correct me if I'm wrong, but I think that not being allowed to count means that you should treat odds as if the cards were extracted from an infinite stack with a given statistical distribution of cards. Reshuffling when you only extracted a low number of cards from a finite stack basically approximates the infinite stack, so, the odds should be exactly as expected.

Except that the stack isn't infinite. There's a statistical difference between playing off a physical deck and playing off a random number generator, and in a physical deck, the dealing of various cards increases the relative odds that the other cards will come up later in the deck. It's the statistical foundation upon which card counting works.

Imagining that the physical deck is a virtual deck does not make it so. In an RNG-populated/virtual deck, there is a small but still real chance that, for instance, 20 aces could be dealt in a row, which is why game programmers use techniques like shuffle bags to prevent that from happening. An "infinite" physical deck, that was actually "infinite", would suffer from the same problem, and would need a physical solution, which would affect the odds which the casino is legally obligated to publish and adhere to.

Re: Beating the bookies – how the online sports betting market is rigged

#139

Post by Bromskloss »

au_gambler wrote: post #27

> A strategy intended to beat the bookmakers at predicting the outcome of sports games requires a more accurate model than the ones bookmakers have developed over many years of data collection and analysis. I disagree with this assumption and I think they have painted themselves into a corner because of it. To illustrate, imagine charting win rates against bins of price-implied-chances. $3 horses win roughly 33% of t…

> I would love to chat with anyone else applying tech/math to beat the bookies. Sorry for the throwaway, I'll put a contact in my profile.

How's that contact information coming along? :-)

Re: Beating the bookies – how the online sports betting market is rigged

#140

Post by phillc73 »

the_cat_kittles wrote: post #135
phillc73 wrote: post #96

Earlier quoted context omitted.

Do you mean the Betfair lines? I think their market is pretty accurate. More so than many traditional bookmakers, although a lot of them use Betfair to make their own markets now, so there's very little chance of arbitrage between them. I've written an R library for the Betfair API[1], which I use every day to retrieve prices. https://www.github.com/phillc73/abettor

sorry i meant accurate in terms of what they show on the site vs what you can actually get when you try to trade. someone else answered that they are indeed accurate- has that been your experience?

The Betfair prices depend on market depth. It's data available through the API, so you can have a pretty good idea of what price you will be able to strike for any given bet size.

My experience with traditional bookmakers has been severely limited or closed accounts very quickly. I haven't used a traditional bookmaker for a few years now, betting solely on the exchanges and 90% of the time with Betfair. I do still have a Corals account, which was somewhat un-restricted through leveraging a contact within the company, but I think my max bet is only £200. As I haven't used it for while, I don't like the chances of it staying that way if I started pumping winning bets through it.

There have been various investigations conducted on Betfair prices, and they are usually a few ticks above traditional bookmaker odds. However, the over round on highly liquid Betfair markets is only 1%-2%, whereas a traditional bookmaker is generally significantly higher, more like 110%-120%, depending on the event.

One way to extract the best results from traditional bookmarkers, as far as horse racing is concerned, is to bet with Best Odds Guaranteed. In this scenario, you'll receive a winning payout at the highest price the selection reached, rather than the price at which you struck your bet. This works best in overnight markets, that is placing bets the night before the race. However, this route is also one of the quickest to restriction and closure.

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