Does anyone profit long term?

[coldhardfacts]

Yes BUT if you got the early line before the move, you'd pick up more winners that lost vs. the closing line.

Agree entirely. It is a bit tricky, though, as well as risky in trying to determine which way the line is going to move.

[Dark Horse]

You can win in the stock market and you can win in sports betting.

Winning gamblers have above average intelligence. It would be interesting to do the research, but I'd be wiling to bet that most winning sports bettors were among the smartest kids in the class when they grew up. These are people who understand the process of learning, and who can apply it to different fields.

Do you think a stock broker would speak of his expertise in this way:

'Investing is done by impulse not by managing your money'.

And do you know anybody who would trust his or her money to such a broker?

The odds and people we're up against are very sharp. So don't jump in because you think the gambling gods owe you some easy money. The sad thing in sports betting (as in life) is that people go on for years without learning much, or anything at all, because they don't understand how to learn.

Go learn something new, that you've always liked but have never done, and become very good at it. And, during this process, study the steps it takes to go from beginner to expert. Understand the method. Once you've done that, come back to gambling and try to transfer those same steps to this field. Learning is a universal process, but you have to understand it before you can apply it to whatever field you choose.

[Dazzez]

I responded that, for a number of reasons, it has been my experience that the there is not a correlation between this variance (expected line to actual line) and my winning percentage.

Maybe you should have learned the meaning of the word "variance" before you decided to use it in a sentence?

[VBOMBER]

I think I understand what he is trying to convey, and I have a hypothetical that I would love to have answered for my own educational process (and it may pertain to his situation as well) as I would like to feel confident enough in quantifying my edge to begin using Kelley. This is similar to something Mr. X posted earlier as an example

So let’s say an NBA Totals bettor had the following rates of success on “his lines” vs. the closing line over about 950 “bets” based on his method of handicapping:

Difference of < 2 points (call these non bets) 138-127 (52.1%)
Difference of 2 – 4 points 234-190 (55.2%)
Difference of 4 - 5.5 points 101-90 (52.9%)
Difference of 5.5 – 7 points 79-65 (54.9%)
Difference of 7 -10 points 79-66 (54.5%)
Difference of > 10 points 23-12 (65.7%)


So obviously this player searches for the best line and is happy to find a half point here and there as intuitively he understands this will make a difference in the long run, but in comparing “his line” to the closing line, from 2-10 points off there doesn’t seem to be much difference in his success rate until the line differs significantly (> 10) from “his line” and that is only a sample of 35 plays. In fact the success rate even takes a dip as it moves out.

So my questions are from this limited information:

1) If this player was trying to quantify his edge in order to use Kelly, what would be his best way of going about it? Using the half-point calculator will obviously tell him that the further away “his line” is from the current market line the greater the edge, but obviously this isn’t the case for this player, so should he just group all plays into one theoretical bucket?
2) Should this player be more confident that he has factored in most relevant information when his line does not differ as greatly from the market line (eventually the closing line) as he understands that he should always respect the market’s opinion.
3) Should this player take anything from small sample of 35 where he had the greatest success?
4) Should the player consider that his method of handicapping just predicts market inefficiencies, but does not give him a way to accurately quantify his edge?
5) Would any of these answers change if the player also had a similar distribution over 700 bets (about 250 smaller) the year before?

[Ganchrow]

The very first thing I'd do would be to take a long, hard look at the logic of my model and try to determine what it might be missing. I'd pay particularly close attention to whatever similarities might exist amongst games with an actual line that deviated substantially from the predicted line.

Basically, this is not how a well-behaved model should act and is one thing I personally look for in testing -- specifically, is there a positive correlation between magnitude of deviation from the predicted line and return? If not, I'd tend to judge the model suspect and would probably return to the design phase to try and determine the source of the model's flaw.

You should also be sure to familiarize yourself with techniques of Bayesian inference, which provide a codified methodology for updating prior estimates based on newly available evidence.

[coldhardfacts]

Maybe you should have learned the meaning of the word "variance" before you decided to use it in a sentence?

Main Entry:
var·i·ance Listen to the pronunciation of variance
Pronunciation:
\ˈver-ē-ən(t)s\
Function:
noun
Date:
14th century

1 : the fact, quality, or state of being variable or variant : difference, variation

Good Lord. The level of ignorance of some of the posters on this forum is almost beyond comprehension.

[coldhardfacts]

Here are a couple of extremes cases.

Consider a model that only predicts market inefficiencies, not outcomes. An example would be a model that finds that in a particular league, home underdogs yield a +E.V. of 5% when betting the best line 10 minutes prior to close.

So, with 11 minutes prior to close, you are preparing to make the proper Kelly bet to win 5% of your bankroll on a +6 line. At the 10 minute mark, the line moves to +6.5. Because of the nature of your model, you will assign the same value, and bet the same amount at +6.5 than you would have at +6.

Now consider a math model with perfect information and perfect ability to predict win percentages. This model predicts 4% E.V. at +6. Once the line moves to +6.5, the model will obviously assign more value to the game at +6.5 (unless it predicts that the favorite NEVER wins by exactly 6) and you will properly bet more at +6.5.

I think that most models fall somewhere in between. If your model loves a game at +6 and the market moves to +8 (with no additional information that you are aware of), you most likely have even more value at +8 than you thought you did at +6. However, the move probably also indicates that there is some information not accounted for in your model. You most likely didn't have the edge that you thought you had at +6.

You, sir, have hit the nail on the head.

[Dazzez]

Main Entry:
var·i·ance Listen to the pronunciation of variance
Pronunciation:
\ˈver-ē-ən(t)s\
Function:
noun
Date:
14th century

1 : the fact, quality, or state of being variable or variant : difference, variation

Good Lord. The level of ignorance of some of the posters on this forum is almost beyond comprehension.

You were right and I was wrong.

Don't get too used to it.

[donjuan]

You, sir, have hit the nail on the head.

I wasn't talking about widely available numbers though (widely referred to as the market) but rather off numbers found through line shopping. For example, say you believe the number for a basketball game should be -8, the market is at -5.5. You would make a bet at -5.5, correct? However, if a book like SIA was offering -4.5 with the market still having a consensus of -5.5, you wouldn't increase your bet size even though your edge is now higher?

[coldhardfacts]

You were right and I was wrong.

Don't get too used to it.

Don't worry I won't. I am wrong much more often than I'd like.

[coldhardfacts]

I wasn't talking about widely available numbers though (widely referred to as the market) but rather off numbers found through line shopping. For example, say you believe the number for a basketball game should be -8, the market is at -5.5. You would make a bet at -5.5, correct? However, if a book like SIA was offering -4.5 with the market still having a consensus of -5.5, you wouldn't increase your bet size even though your edge is now higher?

No, I wouldn't, although I would certainly jump on the -4.5.

Let me explain in different terms:

I expect to hit between 55% to 58% of all bets I place (my annual average). So, when I identify a "play" on a particular game, I believe the chances that I will win that game are say, 56%. (Inherent in this assumption, btw, is that I will get the best line available when I make the bet.)

But that doesn't mean that the true chances of my winning that bet are 56%, for reasons like the ones MrX outlined (flaws in my handicapping analysis for this particular game, injuries, other unknown variables, etc.). So, for example, let's say in the example you described, at -8 my chances of winning the bet were really, because of the aforementioned variables, only 49%. At -5 1/2, they jump up to, say 52%, and at -4 1/2 they become 54%.

And suppose there is another game where I have more accurately "fixed" the line, and the best I can lay is 7 1/2. And at that price, because there are fewer variables, or my analysis is more accurate or whatever, the true chances of my winning that bet are actually 55%. If I were to make a larger play on the former game, I'd be betting more on a game that I had a smaller chance of actually winning.

[20Four7]

I wasn't talking about widely available numbers though (widely referred to as the market) but rather off numbers found through line shopping. For example, say you believe the number for a basketball game should be -8, the market is at -5.5. You would make a bet at -5.5, correct? However, if a book like SIA was offering -4.5 with the market still having a consensus of -5.5, you wouldn't increase your bet size even though your edge is now higher?

But after you hit them too often like that they kiss you good bye. I know I don't have an SIA account anymore due to their "off" lines.

[Art Vandeleigh]

So, for example, let's say in the example you described, at -8 my chances of winning the bet were really, because of the aforementioned variables, only 49%. At -5 1/2, they jump up to, say 52%, and at -4 1/2 they become 54%.

Out of 100 situations like this, some of the plays may have percentages as you described. Other times, they may be on the order of 54%, 57%, and 59%, respectively.

[tomcowley]

No, I wouldn't, although I would certainly jump on the -4.5.

Your math understanding is comically bad. You would play the game at -5.5, and by what you've said, expect to win it 56% of the time. With another point from an idiot book that always hangs off-market lines (let's say SIA and NBA), you'd win ~60% of the time. Your excuse for not betting more is that "your bet might not be a good bet to begin with"... but with a GUARANTEED extra 4% chance to win, you aren't confident enough to lay more. There's pretty much no sane range of initial win%s at -5.5 that wouldn't have you increasing your bet by at least 50% with an additional 4% to win.

I encountered a ridiculously misvalued prop last year, to the point it had +odds on a ~-150 proposition. Are you also telling me you wouldn't bet more at +120 than -120? You'd just bet the same amount at the best (good) number you could find because you thought you had an edge?

[coldhardfacts]

Your math understanding is comically bad. You would play the game at -5.5, and by what you've said, expect to win it 56% of the time. With another point from an idiot book that always hangs off-market lines (let's say SIA and NBA), you'd win ~60% of the time. Your excuse for not betting more is that "your bet might not be a good bet to begin with"... but with a GUARANTEED extra 4% chance to win, you aren't confident enough to lay more. There's pretty much no sane range of initial win%s at -5.5 that wouldn't have you increasing your bet by at least 50% with an additional 4% to
win.

I encountered a ridiculously misvalued prop last year, to the point it had +odds on a ~-150 proposition. Are you also telling me you wouldn't bet more at +120 than -120? You'd just bet the same amount at the best (good) number you could find because you thought you had an edge?

Actually, I believe your reading comprehension skills are comically bad.

In the first place, I don't bet props. If you do, and you can win long term, more power to you.

In the second place, if you read my post above, I agree that of course a better line provides me with a much better chance to win any particular game. My point is, it doesn't necessarily provide me with a better chance to win that game VIS-A-VIS OTHER GAMES I AM BETTING. So, it doesn't make any sense for me to bet more on that game than it does on another game where I'm not getting a better line than I expected.

[HeeeHAWWWW]

That may be true about 90% of the public, but the other 10% are not impulsive and do win long term, and a percenatge of that 10% do it exclusively, making a living off of this.

I recall reading somewhere only 2% of sports betters make a profit, and you have to figure a fair chunk of that are just lucky (ie they hit a big parlay).

Of course, it's perfectly possible to make money sports betting, else the bookies wouldn't be booting sharps :-)

[Peep]

My short of it is, the one with the better number wins.

Sometimes the bookie has the better number, some times the player does. Both always believe they do.

I think the 11 is bigger than 10 factor is compensated for by the fact the player can chose a side and does not have to lay a bet on every game.

Simple game.......

[tomcowley]

Refusing to bet a certain type of market is ROFL bad. Not all props require extreme analysis. If you see something that's pretty close to "will the home team win 3 or more opening coinflips in the divisional round (4 games) priced at Yes +160 No -180, and won't bet it...... Why do you hate money? SOme props really are that bad. Hell, the opening flip of the Super Bowl got up to Heads +105 at one point. Props really are that dumb sometimes.

You bet games that have some range to win, let's say 47-63%, for an average of 55% (you will bet some games where you're giving away EV, that's just handicapping life). So you have some bet size that's appropriate for this range of outcomes.

Now, SIA decides to hand you 4% extra equity, so your range is 51%-67%, average 59%. As far as bet-sizing goes, it is ABSOLUTELY IRRELEVANT that this *particular* game could be 51% to win, or a losing bet in general. It is ABSOLUTELY IRRELEVANT that it could be a 53% play while other games could be 60% plays. The only thing that should matter, as far as you're concerned, is the proper bet size for the RANGE of win% that you assign to the event.

Mathematically, the proper bet size is going to be significantly larger for a 51-67% range than a 47-63% range. Your argument against that- that any game out of the new range could still be a losing or below average play- is utterly false if you actually do the math.

[coldhardfacts]

Refusing to bet a certain type of market is ROFL bad. Not all props require extreme analysis. If you see something that's pretty close to "will the home team win 3 or more opening coinflips in the divisional round (4 games) priced at Yes +160 No -180, and won't bet it...... Why do you hate money? SOme props really are that bad. Hell, the opening flip of the Super Bowl got up to Heads +105 at one point. Props really are that dumb sometimes.

You bet games that have some range to win, let's say 47-63%, for an average of 55% (you will bet some games where you're giving away EV, that's just handicapping life). So you have some bet size that's appropriate for this range of outcomes.

Now, SIA decides to hand you 4% extra equity, so your range is 51%-67%, average 59%. As far as bet-sizing goes, it is ABSOLUTELY IRRELEVANT that this *particular* game could be 51% to win, or a losing bet in general. It is ABSOLUTELY IRRELEVANT that it could be a 53% play while other games could be 60% plays. The only thing that should matter, as far as you're concerned, is the proper bet size for the RANGE of win% that you assign to the event.

Mathematically, the proper bet size is going to be significantly larger for a 51-67% range than a 47-63% range. Your argument against that- that any game out of the new range could still be a losing or below average play- is utterly false if you actually do the math.

No sir, I believe your premise is faulty. Who says that bet A is in the 51-67% range and bet B is in the 47-63% range? If I were confident that were the case, of course I would bet more on bet A. My point is that it has been my experience that I can't accurately assign a range of win % to any particular group of bets vis a vis other groups of bets. Not to say I haven't tried - from a number of different angles, not just point spread variance - or that I won't ever develop a basis for doing so, just that I haven't as of now. I AM confident, however, that if certain conditions exist with regard to matchups, favorable odds/lines, etc., I have an advantage in making a play.

As for props, I have never seen a prop bet as blatantly ridiculous as the example you cite. I agree that you can probably find, every once in a while, a prop bet line that is WAY off. But usually, by the time I sort through and analyze all of the available prop bets to identify those, the advantageous line is long gone. As I said, I'm sure there are others, maybe yourself, who have enough stored knowledge about any particular game to quickly identify and pounce on the "off" lines. But for me, it is not a profitable proposition, especially considering all the time involved.

[tomcowley]

If you would make a bet at -5.5, then it logically follows that you believe that the bet has some win% distribution that will be +EG for your bet size. It doesn't matter if you actually know what that distribution is. Then you see an idiot book hanging -4.5. Again, you don't have to know what the win% distribution for -4.5 actually is to say that it is the -5.5 distribution shifted up about 4%. Anything that would have been a 55% play at -5.5 is now a 59% play at -4.5, etc.

You don't have to have the first idea of what these numbers actually are to figure out that you're supposed to bet more. Play around with the kelly calculator.

If a play is 61% vs. 57%, your stake approximately doubles. If your play is an absolutely horrible 33%, then you can risk about an extra 25% if the play is bumped up to 37% and still have the same (negative) expected growth. At 40%, you can risk about 45% more when your play becomes 44%. For every possible win%, you have a significant increase in stake. Failing to increase your stake by at least 50% is simply awful.

[coldhardfacts]

If you would make a bet at -5.5, then it logically follows that you believe that the bet has some win% distribution that will be +EG for your bet size. It doesn't matter if you actually know what that distribution is. Then you see an idiot book hanging -4.5. Again, you don't have to know what the win% distribution for -4.5 actually is to say that it is the -5.5 distribution shifted up about 4%. Anything that would have been a 55% play at -5.5 is now a 59% play at -4.5, etc.

You don't have to have the first idea of what these numbers actually are to figure out that you're supposed to bet more. Play around with the kelly calculator.

If a play is 61% vs. 57%, your stake approximately doubles. If your play is an absolutely horrible 33%, then you can risk about an extra 25% if the play is bumped up to 37% and still have the same (negative) expected growth. At 40%, you can risk about 45% more when your play becomes 44%. For every possible win%, you have a significant increase in stake. Failing to increase your stake by at least 50% is simply awful.

Forget about the "idiot book" argument for a second, since it's been my experience that if you play with "idiot books" that put out consistent bad lines you're either going to get stiffed (worst case scenario), or cut off (in which case betting higher amounts will accelerate the process, thus prematurely killing the goose laying the golden egg).

So, let's just assume that all of my outs are relatively sharp. I'm still going to regularly find off lines, albeit generally not more than 1/2 point - maybe 1 point tops. So again, it comes down to not the fact that one book may or may not have a better line than another book, but, rather, the difference between the points I'm willing to lay (or required to take if I like the dog) BASED ON MY ANALYSIS and the actual point spread available.

Your philosophy only makes sense, at least to me, if I think that the greater the difference between my "expected" line and the actual line I'm able to bet into is relational to my winning percentage. And I'm telling you, because of numerous variables and conditions, it is not.

[durito]

So, do you risk the same on a +500 dog that you would on a -5000 favorite?

Assuming the same edge -- since all of your bets are precisely the same edge.

[coldhardfacts]

So, do you risk the same on a +500 dog that you would on a -5000 favorite?

Assuming the same edge -- since all of your bets are precisely the same edge.

Well, I'm speaking in terms of the daily grind. I might occasionally make small future bets. Two years ago I bet on the Saints to win their division, the NFC, and the Super Bowl. Each future had progressively higher odds, of course. And no, I didn't bet the same amount on each, and I certainly didn't bet my normal amount on any of them.

But bets like these are based on a whole different set of analysis factors than my day to day plays. I would, however, bet the same amount on an 8-5 favorite in baseball as on an 8-5 dog. I know, I know, this means that I'm really betting different amounts on each baseball game, since I don't adjust my wager amount based on the odds. But my feeling here is that I'm going to win just as much in the long run on plays where I'm laying 8-5 as where I'm taking 8-5. In other words, I'll win a greater percentage of the former bets, and a lower percentage of the latter, but in the long run my net will be the same.

And I wouldn't lay 5000-1 on the sun coming up tomorrow.

[BuddyBear]

And I wouldn't lay 5000-1 on the sun coming up tomorrow.

I know I sure would

[durito]

But my feeling here is that I'm going to win just as much in the long run on plays where I'm laying 8-5 as where I'm taking 8-5. In other words, I'll win a greater percentage of the former bets, and a lower percentage of the latter, but in the long run my net will be the same.

Not if you are risking the same on every bet it wont.

[coldhardfacts]

Not if you are risking the same on every bet it wont.

Correct. I meant to say that I'll bet the same number of units (e.g., $500 to win $800 on the dog or $800 to win $500 on the favorite).

[durito]

Correct. I meant to say that I'll bet the same number of units (e.g., $500 to win $800 on the dog or $800 to win $500 on the favorite).

this

but in the long run my net will be the same.

and this do not equate.

at the same edge, you should be betting to win the same amount. you are betting too much on the underdog.

[coldhardfacts]

I don't understand. Maybe I'm not being clear. What I'm saying is, I think that the 8-5 underdogs I bet will win more than the 8-5 favorites I bet will lose. And, my 8-5 favorites will win more than my 8-5 underdogs will lose. And the advantage I gain (i.e., the rate of return) from both of these occurrences is roughly comparable.

Am I missing something?

[reno cool]

if you have same say 1% edge on favorite or longshot your return will be the same based on money risked. If u bet to win than u will make more off favorites assuming u have same # of bets.

Hang in there facts, what your saying makes perfect sense.

since were not dealing with perfect mathematical models it shouldn't be too hard to comprehend why a line move in your favor might not make your bet better.

[pico]

yes.

just ask davydenko

[Art Vandeleigh]

So, let's just assume that all of my outs are relatively sharp. I'm still going to regularly find off lines, albeit generally not more than 1/2 point - maybe 1 point tops. So again, it comes down to not the fact that one book may or may not have a better line than another book, but, rather, the difference between the points I'm willing to lay (or required to take if I like the dog) BASED ON MY ANALYSIS and the actual point spread available.

This is like saying the sun revolves around the earth, and you are the earth.

[tomcowley]

Your philosophy only makes sense, at least to me, if I think that the greater the difference between my "expected" line and the actual line I'm able to bet into is relational to my winning percentage. And I'm telling you, because of numerous variables and conditions, it is not.

What you're probably seeing, if you're only betting at sharp outs, is noise in your data. If you broke your wagers into 2 groups, and in one you actively lineshopped lots of square books and got .5 or 1 pt better in some of the games, expecting that group to have the same winning percentage as the half you didn't try to lineshop square books for is retarded. It's exactly equivalent to saying that a free .5 or 1 doesn't change your win% at all.

[durito]

I don't understand. Maybe I'm not being clear. What I'm saying is, I think that the 8-5 underdogs I bet will win more than the 8-5 favorites I bet will lose. And, my 8-5 favorites will win more than my 8-5 underdogs will lose.

Assuming the same edge, yes of course.

And the advantage I gain (i.e., the rate of return) from both of these occurrences is roughly comparable.

Assuming the same edge, the favorite is the preferable play due to less variance.

Am I missing something?

Yes. If you are tying to maximize bankroll growth you should be betting to win the same amount.

ie at -160 $800 to win $500
and at +160 $312.50 to win $500

[coldhardfacts]

What you're probably seeing, if you're only betting at sharp outs, is noise in your data. If you broke your wagers into 2 groups, and in one you actively lineshopped lots of square books and got .5 or 1 pt better in some of the games, expecting that group to have the same winning percentage as the half you didn't try to lineshop square books for is retarded. It's exactly equivalent to saying that a free .5 or 1 doesn't change your win% at all.

Actually, your conclusion is retarded. What I'm saying is that, of the books I use, I see no pattern to conclude that some are "right" a greater percentage of the time than others in the long run. To then conclude that I shouldn't worry about getting any advantage I can whenever I can is a non sequitur to end all non sequiturs.

[coldhardfacts]

This is like saying the sun revolves around the earth, and you are the earth.

This, like your 2+2=5 analogy, and your previous post about differing percentages, is meaningless without any clarification as to what you mean.

Maybe you know what you're trying to say, and maybe I'm too dumb to figure it out. But my guess is you're too shallow to really analyze anything in depth, or at least express coherently what your thoughts are. So, you resort to idiotic platitudes to try to get your point (whatever it is) across.