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Well, this was supposed to be a thread to help those new to racing. You would have to bet for a
very
long time before you could say with any confidence that your "value" selections were just that, value. In the example I gave from the Racing Post website the 8/1 shot finished fourth, with the three horses ahead of it in the market filling out the first three, as their very own betting line suggested. Now, was that the right bet or not ? Who knows ?! You could simply be throwing money away on horses you have no real right to be betting.
Yes, it is a thread to help those new to racing. I wish someone had told me about the mathematics of betting when I first started. What you told readers of this thread was WRONG. What you are still telling them is WRONG.
With any 8/1 shot, the only thing that matters is whether the punter believes it has a better or worse than 11.1% chance of winning. If yes, he/she should back it, if not he should
not
.
You are using a race where you know the result, in practice nobody knows when placing a bet if a horse is going to win oe not.
Say the other three are 6/4, 7/2 and 5/1. The punter may well know those three individually and collectively have a better chance than his 8/1 shot. But if the punter does NOT believe the 6/4 shot has a better than 40% chance of winning it is a poor bet. If the 7/2 shot is not believed to be a better than 22.2% it is a poor bet. If the 5/1 shot is not believed to be a better than 16.7% it is a poor bet.
One race result does not matter. A punter should be trying to win more than 40% of his bets @ 6/4, 22.2% @ 7/2, 16.7% @ 5/1 and 11.1% @ 8/1; that is all that matters. It is up to him/her to find horses that fit the bill.
If a punter can not see past one race then he/she is doomed to failure.
Value Is EverythingWhen I back a horse I like to think it has a
very good chance
of winning, not simply
a chance
, and that doesn’t necessarily mean only ever backing short priced fancies either. Your method is all very well with years of racing experience behind you, but for a newbie its toxic as it soon begins to erode ones judgment.
It is telling punters falsehoods that is "toxic" Bluebook, once a "newbie" knows the truths of the mathematics of betting – he/she can make use of it.
Of course "experience" helps to evaluate form. You would not expect a trainee stockbroker to know everything there is about shares. But given the RIGHT advice and tools he/she can (after an apprenticeship) start profiting. Please Bluebook, do not make it harder for apprentices.
If you want to back these shorter priced horses just because they have a better chance of winning and not bothering whether they’re value or not – Then even if you are "experienced", you will NOT make a profit in the long run Bluebook.
Value Is EverythingWell, it looks like we’ll have to beg to differ on this one, but for the record :
I’ve never told anyone in this thread to back underlays. In the Racing Post example I gave I simply pointed out that backing the first three in the market was not an option ( all underlays ) while backing the fourth horse wasn’t particularly ssensible either since although
theoretically
overlayed was still a heavy favourite to lose.
Now, you say that the 8/1 shot should be backed. But here’s the thing : let’s say we repeat the race ten times and the 8/1 shot loses in all ten. Were we wrong in our estimate of its chances ? Who knows ? A ten-race sample is simply too small to tell, one way or the other. Well, what about a twenty-race sample then ? Better, but still not conclusive. And that’s just those we make 6/1 that are sent off 8/1 !
I note that Mark Cramer never advocated backing a horse at 100/1 simply because one thinks it should be 50/1. He always set a limit of 6/1 on his contenders, 8/1 in a contentious race. Any horse’s price he set above 6/1 was never a bet, even if he made the horse 12/1 and it went to post at 33/1.
A punter should be trying to win more than 40% of his bets @ 6/4, 22.2% @ 7/2, 16.7% @ 5/1 and 11.1% @ 8/1; that is all that matters. It is up to him/her to find horses that fit the bill.
I agree with the above wholeheartedly, but I repeat : when can you be
sure
that 11.1% of your horses are winning at 8/1 ? Unhappily for some, not until they’ve pissed away their bank betting on 8/1 shots they
thought
should be 6/1 but were actually no better than 10/1, say.
Perhaps those punters would be better served waiting for 8/1 shots they believe have an excellent shot of winning, not merely a "chance", that’s to say a race in which by careful form study they’ve managed to narrow the field down to just a couple of live contenders.
The point I’m raising is a perfectly valid one, but you seem determined not to acknowledge that there is a problem.
Let’s have a look at what you said on page 1 Bluebook.
Clearly, as the number of horses increases our chances of guessing the winner drop markedly. Given most horse races have at least eight runners, giving us just a 12.5% chance of guessing the winner, why would we wish to bet on a horse race as opposed to betting on red or black at roulette ?
Just because the number of horses is 8 does not mean the chance of "guessing the winner" is 12.5%. Not all horses have the same chance of winning.
The answer is that in most races only a handful of runners hold a realistic chance of winning, and if you can establish which horses those are you can increase your
a priori
chance of success.
A punter needs to have an idea of all the horses chances (not just those with a "realistic chance", because each one effects the chances of the others.
Ideally, in a race with any number of runners, from two to forty, we would like to be able to narrow the field of possible winners down to just one. However, in most races there are at least two realistic contenders, and more likely three or four. Still, if you start off with 12 runners and manage to boil down the field to just four contenders, you’ve increased your percentage chances of winning from just 8.3% to 25% !
Oh dear Bluebook, NO you have not "increased your percentage chances of winning from just 8.3% to 25%". Elementary mistake. Not all the 12 runners will have an 8.3% chance of winning. NO horse has zero chance of winning either, so you can NOT just dismiss 3/4 of the field and say they won’t win. Not only is that working out wrong, but you’ve come to the conclusion that all 4 you do believe have a "chance"… have exactly the same chance.
Given our
a priori
chances are greater in small field races, should we stick to betting in those contests ? Not necessarily. There’s nothing intrinsically wrong with making selections in bigger field races as long as you remember this : in order to make betting worthwhile you have to rule out as many horses as possible,
NO you don’t! You can NOT "rule" anyone out, every horse has a chance of winning and must be allowed for in any evaluation of the percentage chances of the field. By all means don’t bet on the outsiders if that’s the way you personally want to bet. But their chance still need to be calculated, because it effects the others chances.
say nine in a twelve-runner race, leaving a short-list of three. The trouble with having to rule out so many runners is that there’s a greater chance of us making a mistake and ruling out the winner as we go. Arguably the same could happen in just a three-runner contest, but it is nevertheless less likely.
Still, the trouble with only ever betting in small field races is that as the size of the field decreases so do the odds, while the opposite is true in bigger field races. A winner in a four-runner race is less likely to return as much as one in a twelve runner contest.
What can we conclude from the above ?
1. Our chances of winning are better in small-field races but the odds are likely to be shorter. To profit from these races our stakes must usually be greater.
2. In bigger-field contests our chances of winning decrease so it is imperative we narrow the field down to the least number of possible winners as we can, ideally just the one, but most likely two to four. Any more than that and we’re starting to guess. Since the odds tend to be greater in these races we can hope to make decent profits with relatively small stakes, if we so wish. We also have the chance now of betting each-way, but more about that later.
NO, the only rule is: To make an over all profit, any available odds for the selection/s must be bigger than the punter’s opinion of the odds.
Value Is EverythingPerhaps the easiest way to think about value is this. If you fancy a horse and feel there is only one other horse that has any real chance of beating yours, odds of evens + are quite acceptable. If there are two dangers, now your looking at 2/1 or better ( you have a 1 in 3 chance of winning ); three dangers = 3/1, and so on. Once you perceive there to be more than three dangers you’d probably be best passing the race altogether.
What!?? That’s absolute rubbish! Just because you’ve narrowed the field down to two, does not mean you can totally dismiss the rest as having zero chance of winning. Neither can you make the conclusion your selection has a 50% (Evens) chance. The same with your "1 in 3" can not be brought down to the basic "2/1". NOT ALL HORSES HAVE THE SAME CHANCE. The same with 3/1 etc.
Let’s say I work out a race as this (percentage, equivelent price, available price):
A 20% 4/1 (3/1)
B 9% 10/1 (14/1)
C 5% 20/1 (16/1)
D 4% 25/1 (50/1)
E 22% 7/2 (11/4)
F 15% 11/2 (6/1)
G 8% 12/1 10/1)
H 8% 12/1 (17/2)
I 5% 20/1 (20/1)
J 4% 25/1 (16/1)With your oh so simplistic way of looking at things – You may well "narrow it down" to two horses, A and E. (Even on my working out those two have by far the best chance of winning). Yet you seem to believe that means they have both got a 50% (Evens) chance. So 3/1 and 11/4 are according to you brilliant bets? And dismiss all the rest as Zero chance of winning. In fact, the chance of all the ones you dismiss as ZERO chance add up. By my reckoning to a combined 58% chance of winning (or to put it in fair odds terms 8/11). Or may be you think it can be narrowed down to 3? With F now included, after all, F has a much better chance than the others. So according to you those 3 possibles are fair 2/1 chances? Even now the ones you dismiss as 0% have by my workings out got a combined chance of 43% (around 11/8), that’s almost twice the chance of E at 22% (or as you now believe 33% 2/1)
It is equally important to know what value
isn’t
.
Yep, value isn’t what you’re making it out to be Bluebook. To work out value a punter must do just that, work it out, not have a far too simplistic selection method that is supposed to find "value".
Always bear in mind the
percentage
chance the odds suggest a horse has of winning. Many people believe that a horse they think should be 20/1 is great value at 50/1 ; not so. Why ? Simply because the horse only has a 6.1% chance of winning in the first place. The 50/1 odds say its chances are just 2% ; wrong to be sure, but the difference is just 4.2%.
Eh?
Where the xxxx did 6.1% come from? 20/1 in fair odds terms is 4.8%. And yes, 50/1 is 2%. So the difference is 4.8 – 2 = 2.8%. You may not think this is a big difference. I don’t know how many 100% books you’ve done Bluebook; but let me tell you at big odds like this a 2.8% difference is an easily good enough margin for error. At big odds you don’t need as big a margin for error as shorter prices. Because they’re easier to quantify, ie the difference of 2.8% is over 58% of 4.8 (2.8 ‘/, 4.8 = 0.583). You’re rarely going to be 58% out in your assessment of a horse’s chance at this kind of price.Now take the case of a horse you think should be evens which is actually 6/4. That represents a whopping 10% difference ( 50% as opposed to 40% chance ). That
is
value, despite the lower odds.
A similar error is made ny people who create their own odds line ( see just such a mistake on Racing Post tv ). They price a race up as follows :
Horse A 2/1
Horse B 9/4
Horse C 5/1
Horse D 8/1
Horse E 16/1
Horse F 33/1The bookies odds are as follows :
Horse A 15/8
Horse B 2/1
Horse C 4/1
Horse D 10/1
Horse E 12/1
Horse F 20/1Only horse D’s odds are better than those from the odds line, 10/1 as opposed to 8/1. Many now reason as follows : "horse D is value since I think it should be 8/1 ( 11.1% ) when it is actually 10/1 with the bookies ( 9.1% ); they have underestimated its chances. That will be my selection". WRONG ! Take another look at your odds line ! You believe that horses A, B and C have a combined chance of nearly 81% of winning this race, so why on earth would you then back horse D ?! In order for it to win it needs three horses to run below form – unlikely. Don’t make this mistake – many do.
NO, it does not neccessarily need "three horses to run below form", there are many reasons why this horse could’ve been priced up at 10/1 and the others 15/8, 2/1 and 4/1. Known ability is just one possible reason.
One can argue that for some punters (particularly newbies) 2% difference between 8/1 (11.1%) and 10/1 (9.1%) is not enough of a margin for error with selections in this price region. But that was NOT the reasoning you put forward Bluebook. You can NOT argue the horse believed to be a fair 8/1 shot is a poor bet, just becuse it has "nearly an 81% chance of losing".
Value Is EverythingYour method appears to boil down to this : throw enough crap at the wall and some is bound to stick.
Here’s a hypothetical Derby field :
1. The Derby’s Most Likely Winner : Evens
2. Next Most Likely : 2/1
3. Good chance : 4/1
4. Reasonable Shot : 6/1
5. Looks a bit outclassed : 9/1
6. Tilting at Windmills : 14/1
7. Class 4 handicap winner : 50/1
8. Class 6 selling winner : 500/1
9. Class 6 selling winner : 500/1Okay. This looks like a two-horse race between 1 and 2 with 3 and 4 holding an outside chance. Who cares what is a "fair" price for horses 5-9 !? But more to the point, how can ANYONE say what a fair price might be for the two selling class entrants, for example ? More realistic is to say : horses 5-9 have a combined chance of, say, 15% of winning this race. To nit pick as to which horse out of 7,8 and 9 has the best chance of
winning
is ludicrous and a waste of valuable time.
A punter should be trying to win more than 40% of his bets @ 6/4, 22.2% @ 7/2, 16.7% @ 5/1 and 11.1% @ 8/1; that is all that matters. It is up to him/her to find horses that fit the bill.
I agree with the above wholeheartedly, but I repeat : when can you be
sure
that 11.1% of your horses are winning at 8/1 ? Unhappily for some, not until they’ve pissed away their bank betting on 8/1 shots they
thought
should be 6/1 but were actually no better than 10/1, say.
Perhaps those punters would be better served waiting for 8/1 shots they believe have an excellent shot of winning, not merely a "chance", that’s to say a race in which by careful form study they’ve managed to narrow the field down to just a couple of live contenders.
The point I’m raising is a perfectly valid one, but you seem determined not to acknowledge that there is a problem.
Bluebook,
Of course, nobody can be "sure" of anything, it is always an informed opinion. But if you want to put it that way…
It is just as difficult to be "sure" of what is a fair 40% 6/4 shot as to be "sure" of what is a fair 11.1% 8/1 shot. May not seem that way to punters. Easy to fool themselves in to thinking 6/4 shots are easier to predict, purely because they will obviously have far more 6/4 winners than 8/1 winners.Of course punters can "wait for 8/1 shots they believe have an excellent shot of winning", if that is what they want to do. It is up to every punter what margin for error he/she wants to build in to their form study. However, you weren’t talking about "margin for error" in your earlier posts… And in practice there are perhaps (yearly) only one or two (if that) 8/1 shots that I make as much as fair 20% chances, let alone an "excellent shot of winning". So are punters going to want so few bets?
Value Is EverythingHere’s a hypothetical Derby field :
1. The Derby’s Most Likely Winner : Evens
2. Next Most Likely : 2/1
3. Good chance : 4/1
4. Reasonable Shot : 6/1
5. Looks a bit outclassed : 9/1
6. Tilting at Windmills : 14/1
7. Class 4 handicap winner : 50/1
8. Class 6 selling winner : 500/1
9. Class 6 selling winner : 500/1Okay. This looks like a two-horse race between 1 and 2 with 3 and 4 holding an outside chance. Who cares what is a "fair" price for horses 5-9 !? But more to the point, how can ANYONE say what a fair price might be for the two selling class entrants, for example ? More realistic is to say : horses 5-9 have a combined chance of, say, 15% of winning this race. To nit pick as to which horse out of 7,8 and 9 has the best chance of
winning
is ludicrous and a waste of valuable time.
136.7% book!In practice Bluebook, the "seller" winners will both be worked out as worse than 0.05% (2000/1) in my 100% book, so you are right, there is no point in giving a percentage to anything worse than a 2000/1 chance. Unless the "Class 4 handicap winner" has improved (in defeat) since his handicap win or won his race with head in chest or likely to improve greatly… Then in practice the horse will have around a 0.1 1000/1 or 0.2% 500/1 chance. So very easy and quick to give a percentage to. And therefore even if available at bigger than my 100% book price – the margin for error would make it impossible to back.
To have an arbitrary amount of 15% for 5 to 9 is not a good idea and far from being "realistic". There are so many things to take in to account and the difference between a good and bad price is so small that such guesswork spoils the assessment… Not only for these horses, but also of numbers 1 to 4; as a smaller or greater percentage (for 5 to 9) than they should be… will inevitably make those 1 to 4 wrong too. Resulting in the time spent being pointless.Value Is EverythingI would not be as hard on you Bluebook, if it was not for the thread title. It would be unfair for newbies to gain false information.
Value Is EverythingBe as hard as you like, I still think your betting approach is flawed. Remember Dick Turpin ?
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