jesse
@ February 8, 2013


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This season, I made weekly predictions of Super Bowl, conference, and division odds for all 32 teams. Now that the season is over, I can evaluate how these predictions performed.

pred vs act occurrence.JPG

The predictions did reasonably well, but in general I tended to be overconfident in my predictions - that is, events were less likely to occur at the high end, and more likely to occur at the low end. There is no single bad-luck event I can point to. Baltimore winning the Super Bowl (and the AFC, for that matter), Washington winning the NFC East, and Denver winning the AFC West were all events which I viewed as highly unlikely either on (and other than Denver, I kept on viewing it skeptically right up until it happened). A further analysis points to exactly where the pain was.

pred vs error.JPG

Almost all of my error was concentrated in events which I predicted would occur between 0-5% of the time. Some of these I was quick to correct (preseason I predicted Atlanta would win the NFC South only 4.8% of the time, but that was up to 92% by week 4). Others it took me awhile to correct (my preseason odds for Washington winning the NFC East were 2.2%, but this was still as low as 3.8% after Week 12). Others I never corrected (in my final simulation after Wild Card weekend, out of 500 runs, Baltimore won the Super Bowl exactly zero times - my computer really hated Baltimore). Despite this late season error, I did get more accurate as the year wore on.

season quarter vs error.JPG

This data will be useful for calibrating my model. It also means that, next season, I should be more accurate. Or maybe next year a mediocre 3-6 team won't suddenly finish the season 7-0 and take the NFC East. (Sorry, still bitter.) (Go Giants.)

 

 



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jesse
@ January 4, 2013


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I looked at NFL win total bets twice: once in June when the lines first came out, and again in August after bettors had some time to chew on them and we got some movement. Now, since I was testing out some betting strategies, I didn't actually play these, but it is still valuable to go back and review my performance.

The idea was that I picked my 10 favorite plays in June, and then if the line moves in August were favorable, I grabbed them again. These are the plays I end up with.

Atlanta Falcons OVER 9 wins (+105) (June line) - win
Miami Dolphins OVER 7.5 wins (-110) (June line) - loss
Miami Dolphons OVER 6.5 wins (+140) (August line) - win
New Orleans OVER 10 wins (-125) (June line) - loss
New Orleans OVER 10 wins (+125) (August line) - loss
Kansas City UNDER 8 wins (-110) (June line) - win
Tampa Bay UNDER 6 wins (-120) (June line) - loss
Tampa Bay UNDER 6 wins (+105) (August line) - loss
San Fransisco OVER 10 wins (+105) (June line) - push
San Fransisco OVER 10 wins (+110) (August line) - push
Indianapolis UNDER 5.5 wins (-135) (June line) - loss
New York Giants UNDER 9.5 wins (-120) (June line) - win
Denver UNDER 9.5 wins (-120) (June line) - loss
Denver UNDER 9 wins (-110) (August line) - loss
St. Louis UNDER 6 wins (-120) (June line) - loss

This... was a disaster. These plays went 4-9-2 for a value of -4.81 betting units. On average, my preseason predictions were off by +/- 3.1 wins. Since the league wins 8 games on average almost by definition (STUPID TIES notwithstanding), +/- 3 is pretty goddamn terrible. Pointing out that my plays are disastrous might be fun for you, but the idea in making predictions is to not only dance around when they are successful, but acknowledge when they have failed so that future predictions may be improved. Let's consider what, to me, appears to be a rather apparent influence on the success or failure (mostly failure) of my predictions.

Of the 32 NFL teams, 6 began the season with new quarterbacks via either the draft or trade. (Not included on this list are teams that changed quarterback via competition, such as Tennessee or Arizona, because replacing a QB this way is unlikely in my opinion to drastically change the quality of play). 7 teams also had new coaches (I am including New Orleans on this list). There is some overlap here, so this covers a total of 11 NFL teams. Here's the list: DEN, NO, IND, JAX, TB, STL, WAS, MIA, OAK, CLE, and SEA.

Average preseason error for these 11 teams: 3.96 wins
Average preseason error for remaining 21 teams: 2.63 wins

This is too big a difference to ignore. Clearly, my system does a very poor job of considering the impact of changes at the quarterback and head coaching spots. What does my top 10 list of June look like if I exclude these 11 teams?

KC UNDER 8 wins (-110)
NYG UNDER 9.5 wins (-120)
SF OVER 10 wins (+105)
PHI UNDER 10 wins (+105)
NE UNDER 12 wins (-110)
ATL OVER 9 wins (+105)
CHI UNDER 8.5 wins (+105)
GB UNDER 12 wins (-110)
PIT OVER 10 wins (-125)
DET OVER 9.5 wins (+105)

In these 10 bets, I would have gone 5-3-2 for +1.75 BU. Stopping at 10 bets is sort of arbitrary. If I include bets for all 21 teams not included on the list above, and exclude those bets which I calculate have a negative value due to the vig, I would have added the following plays:

MIN OVER 6 wins (+100)
CIN OVER 7.5 wins (-130)
BAL OVER 10 wins (-110)
TEN OVER 7 wins (-130)

These plays bring my record to 8-4-2 for +2.52 BU. That's a pretty nice record, in my opinion. (Based on the August lines, I would have gone 7-5-3 for +2.12 BU - and even more dramatic is that on those 11 excluded teams I would have gone 2-2-7.)

Of course, it would be better if my system wasn't so deficient that it can't properly calculate the impact of a new coach or QB. Solving that dilemma will also improve my overall performance because these teams all play each other and interact with each others performance. But reviewing my predictions and identifying deficiencies is an important part of the process.



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jesse
@ December 28, 2012


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I haven't updated this in a few weeks because it didn't really need updating. Denver, New England, Houston, San Fransisco, and Atlanta, in some order, were the top 5 for three straight weeks. And then, suddenly... they weren't.

week 16.JPG

I was actually on the Seattle bandwagon pretty early. In fact, after week 3 I thought there was value in betting them to win the NFC championship and the Super Bowl. But then they sort of faded, and the computer model put them to the side. At least, that was the case before they ran off 3 straight blowouts and climbed all the way to the top of the rankings.

Okay, so technically they are at the top, but it is very close to a 3-way tie between Seattle, New England, and Denver - all are within a couple of percentage points, which is most certainly within the margin of error. What I find amazing about the computer model's projection is that they are the favorite to win the Super Bowl at this point, even though they are NOT the favorite to win their division (the odds of this happening, which require Arizona to beat San Fransisco along with a Seattle victory this weekend, are only 9%). So, Seattle is even with New England and Denver, even though those teams have a good chance at a first round bye and will play at least 1 game at home in the playoffs.

Poor Houston, on the other hand, has had a rather precipitous fall from the top. While they were never the favorite, they had spent 11 straight weeks in the top 5 (including 5 weeks at number 2) before falling off with 2 losses in their last 3 games. I've seen alot of people walking around town proudly wearing their "Houston Texans AFC South 2012 Division Champion" t-shirts. Wear it proud, Houston: it's looking like that's all you are going to get this year.



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jesse
@ December 5, 2012


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week 13.JPG

First, the teams that are completely done. Zero shot. Mark it down.

PHI, WAS, DAL, CAR, NO, DET, MIN, STL, AZ, MIA, NYJ, BUF, TEN, JAX, CLE, SD, KC, OAK.

That's 18 of the leagues' 32 teams. Some of them haven't officially been eliminated from contention yet (DAL, NO, and WAS are still alive for the NFC wild card, and DAL and WAS could still win the NFC East), but they have been eliminated by sucking. Let's look at the rest of the teams, in increasing likelihood of claiming a title this year.

TIER 4: Technically alive, but on life support

IND, PIT, CIN, TB, SEA, BAL

Atlanta is getting all the press for being a fraudulent 1-loss team, but NOBODY in the league is a bigger phony than the Baltimore Ravens. "Finding a way to win" is a euphemism for "lucky as shit." Remember that.

TIER 3: The Lurkers

NYG, GB

NYG has spent some time in the upper tier this year, but when they lay eggs like they did against WAS this past weekend it is hard to take them seriously. Of course, they did beat Green Bay two weeks ago. The Pack and the Bears have a roughly equal shot at the division title, but Chicago is actually better, so I give them much more chance of actually advancing and winning the Super Bowl.

TIER 2: The Contenders

ATL, CHI, SF, HOU, DEN

4 of 5 have a hammerlock on their respective divisions, with only the NFC North still in question. However, all 5 have some question marks. Atlanta has wins of 1, 2, 3, 4 and 4 points this year. The wins count, but they also point out that their record may outstrip their true talent level. Chicago is 8-4, but 7 of them have come against teams that are already out of the Super Bowl hunt. They are 1-4 against contenders. 3 of those losses have come by at least a touchdown (not counting the overtime Seattle game this past weekend). San Fransisco has somehow embroiled itself in a quarterback controversy with 5 weeks left to go*. Houston and Denver have looked the most impressive, but neither has looked as good as the top team.

(*quick sidebar: if Alex Smith loses his starting job to a concussion injury, the only logical conclusion is for players in the future, specifically San Francisco players, to try and conceal future head injuries for fear of losing their jobs as well. Not only is this bad for player health, but it may turn out to be bad for the team in the long run as well. I do not like the decision by John Harbaugh.)

TIER 1: The Favorite

NE

After some early season stumbles that saw their odds drop, a 6-game winning streak since starting 3-3 has put them back at the top of the league (they were also my preseason favorite to take the title). They are sure to win their division. The only mark against them at this point is that they will have to fight to get a first-round bye.



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jesse
@ November 20, 2012


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Up until two weeks ago, this space had been reserved for a weekly posting of fake LVH SuperContest picks and an update on Super Bowl standings. A run of... let's say poor performance took me out of the fake running, so I took a week to recharge and come back strong with some updated standings. Let's take a look.

week 11.JPG

 

What strikes me most since the last update is the disappearance of one-time runaway favorite, the Chicago Bears. The reasons for this are pretty straightforward: after spending 4 straight weeks atop the standings, they lost two in a row to the Texans and San Francisco, the last one via blowout. Green Bay, meanwhile, has gone on a 5-game winning streak to pull into a tie for the division lead. Not only is Chicago no longer the Super Bowl favorite, I now have them as a 2-1 underdog to win their division.

That leaves Houston as a narrow favorite, just edging out San Fransisco, for the Super Bowl lead. Houston just keeps winning and winning and winning, and any AFC team looking to knock them off is now likely to have to do it at Reliant Stadium. This stranglehold on the division, home-field advantage, and a first-round bye are what is currently keeping them separate from the rest of the pack of AFC contenders.

Denver, for their part, continue to be a study in how Bayesian statistics works. At the beginning of the season, I rated their chances of winning the Super Bowl at something not exactly equal to, but very close to, 0%. This initial position (bias, if you prefer) against Denver means that it took 8 weeks before I even start considering them as a contender. They have now finally reached a point where they can no longer be ignored.



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jesse
@ November 8, 2012


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Let's just get this ugliness over, shall we?

Last week: 1-4 (20%), Overall: 23-20-2 (53.4%), Fake rank: 225 (out of 745)

Ugh.

week 9.JPG

To make matters worse, the Giants took a huge hit to their Super Bowl chances by surrendering a 10-point, 4th-quarter lead to the Steelers. They are basically off the board - in 100 simulated runs, they won zero of them. Part of this is because the Bears are basically sucking up all the oxygen in the room - they are winning the NFC in half of my simulated runs, leaving table scraps for Atlanta, San Fransisco, Green Bay, and the Giants to fight over.

On the flip side, a team that has managed to claw back into their division race with a win is San Diego, who spent he last 3 weeks in a freefall after collapsing late against Denver. Their odds of winning the division nearly doubled after their win last week, increasing from 17% to 31%. Still, Denver remains the favorite for the AFC West. That, along with the AFC North, which is basically a coin flip between Baltimore and Pittsburgh right now, are the only divisions that remain meaningfully competitive at this point.



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jesse
@ October 31, 2012


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I recovered from my 1-3-1 performance last week with another 3-2 week.

Last week: 3-2 (60%), Overall: 22-16-2 (57.9%), Fake rank: 99 (out of 745)

This week's picks:

AZ +11
MIN +4.5
BUF +10.5
KC +7.5
CAR +3

Yes, I picked Arizona again, even after that abominable performance on Monday night. I also have a terrible track record picking against Houston, but here I am again with Buffalo +10.5. So...3-2 again? I'm happy with 3-2 again.

week 8.JPG

 

Am I alone here in not really believing in the Falcons? Nobody from last week's top 5 lost (Houston was on a bye week), but San Fransisco's path to the NFC West became much clearer with losses by both Seattle and Arizona. New England continues to benefit from a weak division. At this point, the odds are being driven by standings, since the following divisions show a winner with 90%+ confidence at this point:

NFC East (Giants win 98% of 100 simulations run)

NFC South (Atlanta, 96%)

NFC North (Chicago, 93%)

NFC West (San Fransisco, 100%)

AFC South (Houston, 100%)

I left New England (89%) and Denver (82%) off this list. The only truly competitive division at this point appears to be the AFC North, with PIttsburgh (37%) and Baltimore (61%) slugging it out.



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jesse
@ October 25, 2012


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With tipoff about a week away, its time to warmup the NBA gambling engine with some win total predictions.

This is my second year with this model, but it is still a work in progress. Personally, it looks to me like it doesn't respect the... curviness that an NBA season seems to have. Just to make sure I wasn't imagining things, I checked the win totals from the last full season, 2010-2011.

 

nba win totals.JPGIt's a subtle difference, but you can see that my model expects there to be one really good team (the Chicago Bulls, by the way), a couple of awful teams (Charlotte and Brooklyn), and then everybody bunched a little closer than usual. Part of this may be the effect of using some data from a strike-shortened season to do my evaluation. Part of it could be a bad model. Or, it could actually be saying that there is more talent than usual spread out around the league and it will be a closely contended season. That, as they say, is why they play the games.

As for the over/unders, here are my projections, listed in order of how strongly I feel about the bets, strongest first. Note that the site I got my lines from had Dallas and Minnesota currently off the board due to injuries.

Brooklyn UNDER 44.5 +110
Houston OVER 30.5 +110
Philly OVER 46.5 +100
Denver UNDER 50.5 +105
Atlanta OVER 42.5 -120
L.A. Lakers UNDER 57.5 -120
Miami UNDER 60.5 -105
Orlando OVER 23.5 +100
OKC UNDER 60.5 -130
Portland OVER 33.5 -110
Chicago OVER 47.5 -135
Boston UNDER 50.5 -110
Toronto OVER 33.5 -140
Washington OVER 27.5 -115
Phoenix OVER 33.5 -110
Memphis UNDER 48.5 -115
Charlotte UNDER 19.5 -120 (I really can't believe I'm taking under on this number)
Indiana OVER 51.5 -115
Milwaukee OVER 36.5 -135
Detroit OVER 31.5 -125
L.A. Clippers UNDER 49.5 -115
Sacramento UNDER 30.5 -105
San Antonio UNDER 55.5 +110
Utah UNDER 42.5 +105

Based on the juice, I've taken an unpopular opinion on Brooklyn, Houston, Philly, Denver, San Antonio, and Utah. I've taken a VERY popular opinion on Milwaukee, Toronto, Chicago, and OKC.

Again, the point here is not to actually bet these lines - it is for me to make a public prediction which I can evaluate at the end of the year to see if I am doing a good job of handicapping these teams.



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jesse
@ October 24, 2012


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 I was due for a losing week, I guess. The lines this week were very sharp: 5 games ended within +/- 1 point of the number. I picked 3 of those games for the SuperContest, and went 0-2-1 in those games. And yes, I'm aware these are bitter whiney sour grapes and I don't care.

Last week: 1-3-1 (25%), Overall: 19-14-2 (57.6%), Fake rank: 154 (out of 745)

This week's picks:

JAX +14

TB +6.5

AZ +6.5

IND +3.5

SEA +2

 

week 7.JPGA new challenger has emerged!

Making their first appearance on the big board are the Chicago Bears, who ROCKET to the #1 spot. This despite 3 of the teams they jumped ahead of winning, and another having a bye week (and still being 6-0). So what's going on here? Is my model whacked?

Well, that's always one possible answer. To consider other possible answers to the question, I ran two versions of my model this week. In addition to the final one, I ran one before the Monday night game, so I could separate out how the Bears performance in that game impacted their standings, vs. what was happening around them in the league. To facilitate this, here is a detailed chart of Chicago's progress.

  chicago week 7.JPG

Let's start by looking at their week-to-week win projections. Chicago's stock has been rising steadily ever since their week 2 loss to Green Bay. This building process is important. Much of sports analysis seems to take place in a vacuum. To use their week 2 opponent as a particularly illustrative example, one week, the Green Bay Packers are losing at Seattle on a bogus official's call, and the punditry is asking what has "happened" to Aaron Rodgers and the Packers. Then the reigning MVP throws 9 TDs and 0 INTs in his next two games, and the story is, do the Packers have their groove back? Both statements were dumb.

Instead, each piece of new information should build upon itself. Based on the Packers recent track record, a couple of early season wins should not be looked upon as the new normal, but as a bump in the road. Even the Saints 0-4 start may have less to do with Bountygate as it did with fluky luck.

That being said, we are now nearly halfway through the season, and your record at this point matters. The Saints are 4 games behind the Falcons with 9 left to play. Thus, their odds to win the division are only 3%. The Packers are trailing the division leading Bears AND the Vikings, leaving only a 7% slice of the division pie for them.

Getting back to my main point: each new data point should move the needle, but by how much? How much data does it take to convince us that what we are seeing is real?

In the case of the Bears, the answer was "alot". But once the model is convinced, each new datapoint will go a long ways towards convincing it that what it is seeing is real. Last week, the Bears were projected to win 10.6 games on average. After everybody else had played, but before the Monday night game, this number was 12.2. After the Monday night game, this increased to 13.2.

Why did they go from 10.6 to 12.2 before they even played? Let's look at their schedule moving forward: Carolina, Tennessee, Houston, San Fransisco, Minnesota, Seattle, Minnesota again, Green Bay, Arizona, Detroit. Collectively, these teams went 6-3 (excluding Detroit). But that doesn't tell the whole story. Only one team (Houston) looked truly impressive in victory. Everybody else either lost, or won by a touchdown or less. After putting a win in the books and Detroit looking pathetic, they gained another game in their expected outcome. Out of the 2.6 win increase modeled for Chicago, only 1.0 had anything to do with their performance Monday night. The other 1.6 had to do with what the rest of their future opponents did, which, other than the Texans, was be mostly mediocre.

This jump from 10.6 to 13.2 basically explains everything else. They went from being projected as the 4th best team in the league to the best. This gives them, on average, better playoff position, more bye weeks, and more home games, in addition to the model just thinking they are better to begin with.

On the one hand, the model's change in opinion regarding Chicago was very drastic this week. On the other, it took several wins in a row before the needle moved on Chicago at all, meaning it wasn't REALLY that drastic. The initial skepticism it had regarding Chicago meant that it took a few weeks to catch up to what somebody with a stronger starting opinion about Chicago might have already thought.



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jesse
@ October 17, 2012


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After 6 weeks of SuperContest picks, making 5 picks a week, I have picked 30 underdogs.This was not a conscious, purposeful decision. I just kept liking underdogs (this week is no different, by the way). Last week was an underdog pickers dream: dogs when 11-2 against the spread. 11-2!!! Unbelievable. So, my record last week must have been 5-0, right? At the very least 4-1?

Nope. 3-2. Only 2 underdogs failed to cover last week, and I picked both of them.

Last week: 3-2 (60%), Overall: 18-11-1 (62.1%), Fake rank: 58 (out of 745)

This week's picks:

BAL +6.5
SEA +7
AZ +6.5
NYJ +10.5
CLE +3

sb week 7.jpg
This was a topsy-turvy weekend by any account, including mine. Of the 5 teams I forecast as the top 5 super bowl contenders, 4 of them lost. Only Baltimore avoided making it a clean sweep, and even then it was a gift from the Cowboys. So why, you may be wondering, did New England's super bowl odds shoot up, from 25% last week to nearly 35% this week?
 
Well... BECAUSE it was such a topsy-turvy weekend. Right now, the NFC appears to be the superior conference to the AFC. But it is for precisely this reason that New England is the Super Bowl favorite - they have an easier path there than any of the NFC contenders. There are currently only 2 teams in the AFC with a winning record: Houston (5-1) and Baltimore (5-1). In the NFC, we have New York (4-2), Atlanta (6-0), Chicago (4-1), Minnesota (4-2), Arizona (4-2), Seattle (4-2), and San Francisco (4-2) - that's 7 teams.
 
However, only one of them can make the Super Bowl. Collectively, their odds of winning it are 39%. But 3 of them are in the same division! Only 6 of them can even make the playoffs, and with 11 weeks to go, there is lots of time for things to change.
 
Now, let's consider New England. In their 3 wins, they have won by margins of 22, 24, and 10 points. In their 3 losses, they have lost by margins of 2, 1, and 1 point. Yes, a win is a win and a loss is a loss, but looking forward, the Patriots look significantly better than their 3-3 record. Baltimore counts among their 5 wins margins of 1 point (over the Patriots), 3 points, and 2 points. Who do you think is going to be the better team going forward?
 
In fact, it seems to be that New England and Houston are likely the class of the AFC (I think my forecast model is being too bearish on Houston at this point). Baltimore is a paper tiger with injuries that will start catching up to them, and soon. Probably this Sunday against Houston.



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