So far, all I have updated is the NFL. I found a free source of data going back to 2006 here. That said, here is what I have found:
Bets Against Spread
Bet | Win | Loss | Push | Win rate | Std dev | Num std dev | Return |
---|---|---|---|---|---|---|---|
All home | 1540 | 1602 | 78 | 49.01% | 1.26% | -0.78 | -6.27% |
All away | 1602 | 1540 | 78 | 50.99% | 1.26% | 0.78 | -2.60% |
All favorite | 1499 | 1584 | 78 | 48.62% | 1.27% | -1.08 | -7.00% |
All underdog | 1584 | 1499 | 78 | 51.38% | 1.27% | 1.08 | -1.87% |
Home underdog | 512 | 495 | 25 | 50.84% | 2.23% | 0.38 | -2.86% |
Home favorite | 1004 | 1072 | 53 | 48.36% | 1.55% | -1.06 | -7.48% |
Away underdog | 1072 | 1004 | 53 | 51.64% | 1.55% | 1.06 | -1.38% |
Away favorite | 495 | 512 | 25 | 49.16% | 2.23% | -0.38 | -6.01% |
Home pick | 24 | 35 | 0 | 40.68% | 9.21% | -1.01 | -22.34% |
Away pick | 35 | 24 | 0 | 59.32% | 9.21% | 1.01 | 13.25% |
All | 3142 | 3142 | 156 | 50.00% | 0.89% | 0.00 | -4.44% |
Not surprisingly, underdogs do better than favorites. What is a little surprising is away teams to better than home teams. I also indicate a standard deviation of the win rate. The only categories that are one standard deviation up, assuming every bet had a 50% chance of winning, is all underdogs and away underdogs.
Over/Under
Here is a summary of over/under bets:
Bet | Win | Loss | Push | Win rate | Std dev | Num std dev | Return |
---|---|---|---|---|---|---|---|
Over | 1586 | 1576 | 58 | 50.16% | 1.26% | 0.13 | -4.17% |
Under | 1576 | 1586 | 58 | 49.84% | 1.26% | -0.13 | -4.76% |
I am surprised that over bets very slightly outperformed under bets. I had expected unders to do a little better. Both are very close to the 50% win rate expectation.
Money Lines
With money line bets, not surprisingly underdogs did better than favorites. The following table shows the rate of return on money line bets.
Bet | Return |
---|---|
Underdog | -3.91% |
Favorite | -6.24% |
All | -5.08% |
Next is an updated look at my Probability of underdog winning by spread. The "Prob. win" column is the actual probability an underdog with this spread won. The "Estimated" column attempts to tease out the variance by smoothing out the ups and downs.
spread | spread | games | wins | Prob. Win | Estimated | Fair |
---|---|---|---|---|---|---|
0 | 0 | 154 | 77 | 50.0% | 50.0% | 100 |
1 | 1 | 139 | 69 | 49.6% | 46.4% | 115 |
1.5 | 1.5 | 88 | 43 | 48.9% | 44.6% | 124 |
2 | 2 | 126 | 51 | 40.5% | 42.9% | 133 |
2.5 | 2.5 | 224 | 98 | 43.8% | 41.1% | 143 |
3 | 3 | 517 | 235 | 45.5% | 39.4% | 154 |
3.5 | 3.5 | 279 | 107 | 38.4% | 37.7% | 165 |
4 | 4 | 157 | 59 | 37.6% | 36.1% | 177 |
4.5 | 4.5 | 128 | 47 | 36.7% | 34.4% | 191 |
5 | 5 | 89 | 23 | 25.8% | 32.8% | 205 |
5.5 | 5.5 | 118 | 38 | 32.2% | 31.3% | 220 |
6 | 6 | 133 | 45 | 33.8% | 29.7% | 236 |
6.5 | 6.5 | 147 | 42 | 28.6% | 28.3% | 254 |
7 | 7 | 220 | 51 | 23.2% | 26.8% | 273 |
7.5 | 7.5 | 146 | 36 | 24.7% | 25.5% | 293 |
8 | 8 | 65 | 14 | 21.5% | 24.1% | 315 |
8.5 | 8.5 | 52 | 16 | 30.8% | 22.8% | 338 |
9 | 9 | 58 | 13 | 22.4% | 21.6% | 363 |
9.5 | 9.5 | 48 | 6 | 12.5% | 20.4% | 390 |
10 | 10 | 104 | 19 | 18.3% | 19.3% | 419 |
10.5 | 10.5 | 61 | 15 | 24.6% | 18.2% | 450 |
11 | 11 | 41 | 4 | 9.8% | 17.1% | 483 |
11.5 | 11.5 | 22 | 4 | 18.2% | 16.1% | 519 |
12 | 12 | 13 | 3 | 23.1% | 15.2% | 558 |
12.5 | 12.5 | 25 | 4 | 16.0% | 14.3% | 599 |
13 | 13 | 34 | 6 | 17.6% | 13.4% | 644 |
13.5 | 13.5 | 36 | 4 | 11.1% | 12.6% | 692 |
14 | 14 | 36 | 3 | 8.3% | 11.9% | 743 |
14.5 | 14.5 | 12 | 1 | 8.3% | 11.1% | 798 |
This differs quite a bit from my previous look at this, as seen from the link above. The old data was 1994 to 2013. Again, the new data is 2006 to 2017. For example, I previously said a 7-point underdog had a fair money line at +253. Now I say it is +273. No wonder I haven't been doing well on underdog money line bets (this is not a joke).
Any questions on the NFL. I also want to look at the NBA, NHL, MLB, and NCAAF. I need data for these sports, if anyone has anything up to date.
Sport Name. Alternative Names.
Season start.
Season end.
Differences between conferences, leagues, teams, etc.
General reputation for honesty in the sport.
General reputation for honesty in the officiating.
Sites for further information.
Sites for last minute information.
Quote: FleaStiffFor the revised edition can we have a general introduction:
Sport Name. Alternative Names.
Season start.
Season end.
Differences between conferences, leagues, teams, etc.
General reputation for honesty in the sport.
General reputation for honesty in the officiating.
Sites for further information.
Sites for last minute information.
Why don't you just have him settle the lawsuits now?
Keep in mind that, technically, the book can't use the trademarks NFL, NBA, Major League Baseball, NHL, or NCAA, or any of the professional team or athletic conference names without permission, and while most of the time, the leagues don't really care (the only two phrases I have seen set off alarm bells are "Olympics" and "Super Bowl"), they can play the trademark card if necessary for some other purpose.
A few questions you might want to consider for any chapters sports:
-probability for each margin of victory / push rates / value of half-point on or off each number
-easy to find correlated parlays. Baseball home-and-under, road-and-over, etc.
-How the leagues changes over time can effect databases. Larger sample is obviously better, but having to go back over 10 years means looking at a slightly different game. NFL scoring jumped slightly right after 2006, which I think is the reason for more overs during this specific 12 year stretch
Quote: TomG-probability for each margin of victory / push rates / value of half-point on or off each number
Good suggestion. Previous analysis has shown paying 10 basis point for an extra half point is only worth it off of 3 and 7. Usually, they don't let you buy it off 3.
Quote:-easy to find correlated parlays. Baseball home-and-under, road-and-over, etc.
Yes, I love those baseball correlated parlays. Good suggestion.
Quote:-How the leagues changes over time can effect databases. Larger sample is obviously better, but having to go back over 10 years means looking at a slightly different game. NFL scoring jumped slightly right after 2006, which I think is the reason for more overs during this specific 12 year stretch
A very good question is how far back should you go, assuming time was no issue. As you said, more data is always better, but what if it is stale data? The NFL is not the same as it was before rules were put in place to put a ball and chain on defenses, in an effort to reduce head trauma. Field goal kickers are also much better than they were ten years ago.
The basic info on NFL sports betting that I would like to see is percentage of games decided by 1 point, 2 points, 3points, etc. In other words, as the line shifts from +3.0 points to +3.5 points how much of a percentage advantage is that?
The information that you provide in the tables leads me to conclude that almost none of those win percentages is any different than 50%, and the variations you discern are not distinguishable from statistical noise.
When I sit around with buddies, these are the type of comments that I hear about picking NFL games:
Denver is known to have a larger home field advantage than most teams, as is Miami during the first month of the season (because of the heat).
Home field advantage is arguably less important in the first week of the season when your starters are not recovering from a physically punishing game.
High game temperatures have recently been shown to be slightly correlated with winning UNDER bets, presumably because the heat makes the offensive linemen wilt as the game goes along.
Traveling across multiple time zones leads to a larger disadvantage for the traveling team, particularly for
- East coast teams traveling to the west coast for afternoon or evening games
- West coast teams traveling to the east coast for 1:00 pm games.
Will later chapters in your book address issues like these?
Quote: WizardGood suggestion. Previous analysis has shown paying 10 basis point for an extra half point is only worth it off of 3 and 7. Usually, they don't let you buy it off 3.
Can buy on or off the 3 for 20-cents some places. Seems like that must be a good bet if either the -2.5, +3.5 or +-3 are also good. Most of Las Vegas is 30-cents for the places that allow it.
Any idea what the other numbers are worth?
Home field advantage: Can always take home team winning percentage (58% in NFL, I think) and convert it into a no-vig moneyline, somewhere around -135 to -140. That would be a 2.5 spread (according to wizard of odds). So home field in the NFL *should* be worth 2.5 points based on that. Most people usually say it's worth 3. That would explain why road teams have done slightly better overall since 2006.
But why do home teams have an advantage? Travel and time-zone changes if often cited as one reason. That would mean out-of-division and out-of-conference games would see a bigger home field advantage than games within a division or conference. Is this true? To what extent.
Can also spend some words talking about prop bets. I often like to use the sportsbooks themselves to handicap bets. Always do great on the baseball first inning run. Wait until close to game time, sometimes the total will move quite a bit from the morning, but the score in the first inning prop won't. There should be a good bet to be made. Always a lot of great opportunities for that in the Super Bowl.
Quote: TomGCan buy on or off the 3 for 20-cents some places. Seems like that must be a good bet if either the -2.5, +3.5 or +-3 are also good. Most of Las Vegas is 30-cents for the places that allow it.
Any idea what the other numbers are worth?
Here are the results of a quite a bit of number crunching -- the fair price to pay for a half point off of certain key spreads:
Spread | Fair price |
---|---|
3 | 128.1 |
4 | 116.9 |
7 | 121.9 |
10 | 117.9 |
14 | 117.0 |
For example, to buy the half point off of three (meaning -3.5, -3, +2.5, or +3), a fair price to lay would be 128.1 to win 100, to get you the same return as a random picker without the extra half point, who gets back 21/22 = 95.45%.
The bottom line is that it is only worth it to lay the 120 off of 3 and 7. Definitely do it off of 3 and there it is slightly worth it off of 7.
Quote:But why do home teams have an advantage?
If there are more than a few posts about this, I'll split if off. The book Scorecasting spends many pages on this question. The bottom line is money -- sports makes more money if the HOME team wins. People are willing to pay more for tickets for a winning team. While I'm sure every referee would vehemently deny any bias, they present a very good case the referees call many more penalties against visiting teams and shrink the strike zone for them in baseball, and expand it for the home team. They convinced me.
Quote: WizardHere are the results of a quite a bit of number crunching -- the fair price to pay for a half point off of certain key spreads:
Spread Fair price 3 128.1 4 116.9 7 121.9 10 117.9 14 117.0
For example, to buy the half point off of three (meaning -3.5, -3, +2.5, or +3), a fair price to lay would be 128.1 to win 100, to get you the same return as a random picker without the extra half point, who gets back 21/22 = 95.45%.
The bottom line is that it is only worth it to lay the 120 off of 3 and 7. Definitely do it off of 3 and there it is slightly worth it off of 7.
If there are more than a few posts about this, I'll split if off. The book Scorecasting spends many pages on this question. The bottom line is money -- sports makes more money if the HOME team wins. People are willing to pay more for tickets for a winning team. While I'm sure every referee would vehemently deny any bias, they present a very good case the referees call many more penalties against visiting teams and shrink the strike zone for them in baseball, and expand it for the home team. They convinced me.
That’s a cool chart! I’d love to see a database that has the opening and closing lines so you could analyze what line drift is worth, and test the old adage to bet against the trend if the line drifts by two points.
Quote: Wizard
Not surprisingly, underdogs do better than favorites. What is a little surprising is away teams to better than home teams. I also indicate a standard deviation of the win rate. The only categories that are one standard deviation up, assuming every bet had a 50% chance of winning, is all underdogs and away underdogs.
This one is simple, the public (or books) simply over favor home teams by too much. While it jumps out significantly in the PK category (limited sample size) Away performs better than Home in every other category, as well.
Quote: unJonThat’s a cool chart! I’d love to see a database that has the opening and closing lines so you could analyze what line drift is worth, and test the old adage to bet against the trend if the line drifts by two points.
I got the data here. Click on the name of the spreadsheet just under "download." It has opening and closing lines for only 2014 to 2017. Before that, there is just one line.
I've looked at this before, and line movements are generally in the correct direction. I've never analyzed that two-point rule, but with only four seasons of data showing point movement, I don't think any results would be conclusive. My instinct is that there is generally good reason for big line movements, but not always. The squares will always over-compensate if a factor is all over the news, like when Ray Lewis got suspended.
Quote: Mission146This one is simple, the public (or books) simply over favor home teams by too much. While it jumps out significantly in the PK category (limited sample size) Away performs better than Home in every other category, as well.
I tend to think the home field advantage is overstated in the NFL. The rule of thumb is it is worth three points. However, since 2006, the average home score is only 2.41 points more than away.
Just recently, the NBA has drastically reduced back-to-backs and the popular sharp betting favorite, the 4 games in 5 nights to prpvide more rest for its players. Both of these had a lot of value over the years from my research and backtesting, especially when the team traveling on the backend of the back-to-back was playing in Denver the following night. Now with fewer of these occurrences happening due to the new commissioner cutting back on it, the data will be skewed, so you have to be careful. Also the removal of handchecking and the late 90s and early 2000s resultimg in 'softer' play has also affected the game in so many ways, especially the over/under where teams now can score a lot easuer resulting in more free throws and softer defense resulting in more points.
how and why is it different from "st dev"?
I get that "std dev" means standard deviation
I just don't get the "num" part and what it means. I'm assuming it stands for "numerical". but I still don't understand it.
thanks
Take into account any information or factors that are usually overlooked or incorrectly evaluated in the process that goes into establishing the line.
Sometimes you're a fan of the Purdue Boilermakers and just know more than the bookmakers about what's happening with that team. Or maybe you've discovered that a certain team's secondary struggles to cover tall left-handed wide receivers. Or you believe that the addition of that new player puts his new team beyond "the tipping point" and in combination with the existing players, the team has just gotten much better than it was.
But, you can't just watch a game and say "Wow, the Rams/Eagles are really good" and expect that the line doesn't already reflect the game you just watched pretty accurately. Also, don't expect to get an edge against the line by listening to an ESPN talk show - everybody on ESPN has pretty much the same opinion and every bookmaker and bettor is exposed to that stuff. You've got to find and think about information and analyses that aren't discussed incessantly on ESPN.
Quote: lilredroosterin your main chart what does "num std dev" mean?
how and why is it different from "st dev"?
I get that "std dev" means standard deviation
I just don't get the "num" part and what it means. I'm assuming it stands for "numerical". but I still don't understand it.
That's how many standard deviations the actual results are from expectations. It helps to answer the question of how much of the expected are due to true advantage and how much to luck.
Quote: djatcshopping for the best line on Vegas Dave's picks is the most important thing
Fyp
shopping for the best line = the most important thing.Quote: djatcshopping for the best line is the most important thing
btw,
'the most important thing' is Uncommon Sense
another poorly written and extremely
biased book to avoid reading, imo, of course.
when sports betting becomes involved...
betting on the favorite should be made earlier than later
except when only U know how much U want to win (and how much cash you actually have)...
betting on the dog should be done later than earlier
unless you know Ur gut feeling is from week old pizza
Sally
Quote: RigondeauxFyp
*Diamond Dave or Steve or whatever his name was:
context: I was betting superb owl bets at Westgate and some dude in front of me was saying Diamond Jim says that the Falcons are a sure thing so he was putting money on it. I thought he was just some rando with like 11 bucks but turns out he had a stack of $100s (about 10k) so I guess he's a big time bettor.
" I also want to look at the NBA, NHL, MLB, and NCAAF. I need data for these sports, if anyone has anything up to date."
covers.com is the best site I know for historical stats. they provide them but they don't compile the info. lots of drudgery in going thru them all to get what you want. but anyway they're there. i.e. in their NBA standings pages (linked) they give you each team's ATS and o/u record for each year. in their NBA scores pages (linked) they give you the spread, total and line history on each game. their data goes back several years, I'm not sure how many. in the NBA they don't provide moneyline data.
https://www.covers.com/pageloader/pageloader.aspx?page=/data/nba/standings/2016-2017/league/standings.html
https://www.covers.com/sports/NBA/matchups?selectedDate=2018-1-13
Quote: WizardThis is the kind of thing I spend much of my time on, updating old stuff. The last week or so I've been plugging away at updating my sports betting page. Many things have been changed and updated since I started this thread. Again, I welcome all feedback.
I'm late to the thread, but IMHO a big theme should remain how few games a person should really be betting and how good most lines are. I just re-read my coin-flip season bets in my bloc and had forgotten how close that thing was and how much the vig ate away at your bankroll.
I just read a book on the last days of the Stardust book and the motley crew that made it their life. Theme there was you have to hit the unknown teams the book cannot follow as well and look for the bad lines.
Quote: AZDuffman
Theme there was you have to hit the unknown teams the book cannot follow as well and look for the bad lines.
That is why college football and basketball are so much better to bet on than professional sports. So many more opportunities to find lines that are off.
Quote: DRichThat is why college football and basketball are so much better to bet on than professional sports. So many more opportunities to find lines that are off.
Oh, agreed. Rosenthal once told Spilotro (when they were still in Chicago) there were only 2 good college hoops bets one weekend. Spilotro went nuts.
I played with some simple NFL spreadsheets and it is amazing how teams go to form and how the lines already know this. No wonder after the Stardust closed nobody was hot to take the honor of opening the lines.
Do you have any data to back that up?Quote: mustangsallybetting on the favorite should be made earlier than later
betting on the dog should be done later than earlier
I bet only dogs in NFL but I often make my bets early (like Tuesday/Wednesday). I would change that if I saw supporting data
Quote: Ace2Do you have any data to back that up?
I actually do have some data that could prove or disprove it. Perhaps I'll make that an Ask the Wizard question. My personal opinion is this effect is probably true, in general, but very slight.
In other news, I think I've finished my update of my Betting the NFL page. Many fair lines have moved based on the different period of data. If you bet the NFL at all, I would suggest a revisit of the page if you haven't been there in the last month.
As always, I welcome all questions, comments, and corrections.
Quote: DRichThat is why college football and basketball are so much better to bet on than professional sports. So many more opportunities to find lines that are off.
Obscure sports as well. If you know a lot about professional tennis or golf, I imagine those can be good. Perhaps WNBA or soccer (although that has been growing in interest.) Martials arts.
how do you bet the game(s)?Quote: Ace2Do you have any data to back that up?
the data I have is only for 2 years and is for the NFL money line and point spread open and close.
I did not put it together
as it takes a lot of time and effort.
I was looking into that this season but am finishing my studies on MLB Grand Slam Home Run betting.
I find everyone loves a grand slam!
+EV for last year and this year!
*****
other sports are way different.
MLB has so many games every day and little is done with run lines.
NBA gets weird because of all the travel days and back to back games.
NCAAF and NCAAB has lots of games and that makes many games lines not even move from open to close.
I find so many nowadaysQuote: Ace2I bet only dogs in NFL but I often make my bets early (like Tuesday/Wednesday). I would change that if I saw supporting data
betting the moneyline and the point spread on the same game.
That can get very interesting,
especially when one can bet during the game as long as the game is not a blowout, the money line and point spread changes can get wild.
I know, because I wait until one team is winning, then try to bet the moneyline on them only to have that current play a long pass play for example and the lines are suspended for a short time.
that makes it a no bet, especially if they score a touchdown and just the point spread is available during the game.
Sally
Quote: gordonm888Obscure sports as well. If you know a lot about professional tennis or golf, I imagine those can be good. Perhaps WNBA or soccer (although that has been growing in interest.) Martials arts.
Only hard part there might be finding action.
I did ask, and that is what was briefly explained (given the long lines I didn't pursue it further), but I do not know if the parlay card payouts also differ from an off the board parlay.
They did have a nice feature that it now included a round robin pick...i.e. play a 6 team card, but you could pick for example a 5 team round robin pick and it plays all the 5 team combinations for you (for 6 times the wager.). Saves filling out six cards.
I just goof around with the parlay cards for fun while attaching the game, so no real effect for me. but if places go to this, your 1/2 point parlay card strategy may become a thing of the past in coming years.
I show no significant difference between betting home and road teams. Road teams performed a little better, but was within the margin of error. Not surprisingly, I show under bets performed better than overs. Laying 1.5 runs on the run line was better than getting the 1.5 runs.
Overall, the baseball market is much more efficient than the NFL.
Quote: TomGSome time ago heard some radio interview where the advised that "recreational" bettors would be better off by simply never laying 10+ points in the NFL. Which must be true, because it means less action. Might be something worth looking into a little deeper, though. I think NFL underdogs of 20 or more have a great record, but probably too few games. With the Bills at +17 (and some +17.5s on the cards), might be worth looking into historical records of all games with spreads over 10, 14, 17, 20, and seeing if there is any sort of "basic strategy" on those games
I haven’t looked at any data but have the opposite impression. That really big lines aren’t big enough, really high overs aren’t high enough and really low unders aren’t low enough. I recall a year the Patriots were blowing out everyone but the line never wanted to go much above 14. That was easy money.
Would be really interested to see what the data say.
Quote: TomGIn 2007 the Patriots went 10-9 against the spread while out scoring their opponents by 340 points, or 18 per game. The “easy” money came from betting against them in the second half of the season
Interesting. Thanks for this.
Here’s a question. I think over/unders should have the same “accuracy” and standard deviation as the spread since the two are just algebraic transformations of the same variables: either add or subtract final scores. Is that true in the data?
As always, I welcome all questions and comments.