so i was scrolling across facebook one day and i came across the sportsbet multi-page and i saw a couple of these posts and i thought why are these people so proud of getting ripped off do they not realize they're pretty much just being scammed the average bloke donates about twelve hundred and sixty dollars to the bookies from their gambling habits and that's quite a lot of money if you think just because you watch some sports and you're a bit of a fan you think you might know when a bet is a sure thing or a lock or a guaranteed and when you do end up losing you just say oh it was just down to bad luck well you're actually probably one of the favorite customers that bookies like to prey on in today's video i'll be proving mathematically how bookies are ripping you off and bleeding you dry i put a knife in opened up those wands you were bleeding it all out hi everyone my name is shane and i've been doing match betting or arbitrage betting for a while now which relies heavily on understanding mathematical probabilities and payoffs to make a profit from the bookies first let's start with a single example of a 50 50 bet we can easily find this for example on a coin toss or when there's two teams playing against each other and there's only two possible outcomes and the favorite team is given the handicap and it makes the odds more closer to very much 50 50. firstly in all the examples i'm showing you here the odds are not the fair rides of two which we should be obviously expecting but rather they're less than two for example 1.90 or 1.87 and you can clearly see that this is not fair so how much exactly are they ripping you off by we can work this out by using something called ev which stands for expected value it's a term commonly used in finance and investment industries and is used to calculate the expected profit or loss without regarding the risk or the variance involved in the long term luck doesn't play much of a part at all and it actually fades the longer you bet for to calculate ev you do the sum of the probabilities multiplied by the respective payoffs whether that be a profit or loss you can be pretty sure that from the bookies each one of these ev calculations is going to be negative so you're expecting to lose money so let's say you place 10 on a 50 50 bet for example in this case the line bet there's a 50 chance you make nine dollars which is 1.9 minus one times your stake and there's a 50 chance you don't make anything and lose your initial stake of ten dollars so the expected value in this case becomes 4.50 minus five dollars which is negative fifty cents on a ten dollar bet you might think this is only fifty cents or five percent of your bet stake but this is just the beginning and it gets a lot worse we can then extrapolate this ev calculation to every other bet market out there for example head to head correct score big win little win first scorer and everything else this is because we can actually find the exact probability of an outcome occurring by using the betting market or the betting exchange the betting exchange represents the fair market prices similar to what a stock market is like there's people willing to buy or bet on for a certain price and there's people willing to bet against or sell at a certain price here on this betting exchange the blue means back or bet on similar to what you would do on the bookie site and pink here means lay or bet against as you can see i can back italy to win at two dollars and 32 cents on the pink or lay side i can bet against italy at odds of 2.34 for this to happen someone wants to bet on italy to win if the odds are 2.34 and we will be the bookmaker effectively in this case by taking their bet therefore we can see from the back and the lay side the fair price of italy to win is somewhere in the middle the midpoint so 2.32 plus 2.34 is 2.33 these are known as the market odds and we can pretty much just treat these as the fair rods since this is the sum of pretty much a lot of people's opinions it's similar to looking at for example the price of after pay stock people are willing to buy it at this price and people are willing to sell it at this price so that means the fair price is probably somewhere in the middle we can then easily convert from odds to probabilities using the simple equation probability equals 1 over the odds now let's take a look at the bookies odds we will see that for each the odds are less than the odds on the market so we are already getting a little bit ripped off here the odds of 2.2 for italy to win means for example for a 10 bet we will get 12 profit if they do win and lose our 10 stake if it happens to be a draw or spain wins i.e italy doesn't win we can then calculate our ev so the first term of our ev is our 12 profit multiplied by the likelihood of that happening which we calculated using one over the fair odds which gives us 42.9 percent and we minus the other outcome which is our a loss of 10 multiplied by the probability of that happening which is every other outcome except for italy to win which means it's 57.1 and we sum up these two terms to give us negative 0.562 this is like buying something that should be worth 9.44 but the bookmakers are charging you 10 instead this is even worse when it comes to high odd events for example let's take a look at the correct score markets as an example here nil nil is paying odds of six but the probability is one over the average of nine and nine point four which is one over nine point two as you can see from the betting exchange again we can now calculate our ev the first case if we do win the bet we will win fifty dollars our sixty dollars winnings minus our ten dollar stake is our profit of fifty dollars multiplied by ten point nine percent and the other outcome is we lose our ten dollar stake and the likelihood of that happening is eighty nine point one percent this therefore gives us an ev of negative three dollars and forty six cents per ten dollar that we place which means we expect to lose about thirty five percent of our money or we're getting ripped off by about thirty five percent now after the higher events it gets even worse let's say we want to do a multi-bet because it's more exciting and higher risk means higher reward right it's true but it means higher rewards for the bookies and not you the punter let's consider a two leg multi we're gonna place ten dollars with the first leg of the malti being belgium to win one nil against france and our second leg is for italy and spain to play out to a nil or draw these are uncorrelated since they are completely separate events so you might think odds of 39 which is 6 times 6.5 is fair but it's not the fair rods as we saw on the market were 9.2 and 9.8 so the real odds of both happening is 9.2 multiplied by 9.8 which is 90.16 this means that true probability is 1 over 90.16 which is 1.109 percent we then do the ev calculations on a 10 bet we see that in the long term if we keep placing these bets we're going to be losing 5.66 per 10 that we place which is expecting to lose more than half our money in the long term it gets even worse for three leg and four leg multis here we can see that for a three leg multi where we've put the initial two legs from our previous two leg multi plus we've added in for a horse called antonio giovanni to win which is paying five odds we see that we are have the potential to make 1 940 profit but the probability of this happening is so small if we look at the actual fare odds from betfair or the betting exchange this is like 0.161 percent and if we do the ev calculation in this case we can see that on average we're expecting to lose 6.88 this is now like buying something that's actually only worth 10 minus 6.88 which is only worth three dollars and twelve cents but the bookies are charging us still the full ten dollars and you can pretty much just think of it as a donation to the bookies if you're ever putting on a 10 leg multi or higher so why are these odds so bad for maltese it's because it's compounding and multiplying by itself over and over again how much you are getting ripped off by each time and that's why bookings make so much money off people yes every now and then you might have one person or two win a huge multi and this will go on to the sportsbet multi page or they might even post something where they were just one leg away to make it seem like can be ever so close to winning and maybe just by putting in 10 you can make many thousands but for every one of those people there's probably a hundred thousand or even millions of people who've lost money instead and of course they're not going to be showing their bets this is why betting can be very dangerous so the best way to stop losing money is pretty much well firstly to stop betting altogether this way you can't be giving any more money to the bookmakers you can also use the betting exchange that i showed you earlier but this is a very very dangerous tool even though the odds are generally fairer there is commission that you have to pay also it is very very easy to make mistakes and get ripped off and lose a lot of money there are also other routes such as arbitrage betting or matched betting which means betting in such a way that you're guaranteed a profit no matter what but it involves very complex strategies and betting on multiple outcomes so i highly recommend that you make sure you understand everything and learn all the knowledge before getting into that as well now if you still want to bet and just go for a punt then by all means do whatever you want but just know that the odds are very much against you and the more legs that you're adding to your maltese the more you're getting ripped off by hope you guys can all learn something and see some mathematics being used in an interesting way if you enjoyed this video then make sure to give it a big like down below and subscribe to this channel to not miss out on my future content where i give other money making tips and educational advice as always take care and i hope to see you guys in the next video