Podcast: New Orleans and Super Bowl win probabilities

New Orleans might be the most complete NFL team on both sides of the ball. I break down the Saints and their odds to win the Super Bowl.

To listen, click on the right pointing triangle.

Atlanta coach Mike Smith made the correct, aggressive call

On 4th and inches
Smart coach makes aggressive call
Life spits in his face

In overtime against the New Orleans Saints, the Atlanta Falcons faced a 4th and inches from their own 29 yard line. Atlanta coach Mike Smith decided to go for it, which backfired when running back Michael Turner gets stuffed for no gain. (See 3:25 of these highlights from the game.) New Orleans promptly drove down the field and kicked a game winning field goal. The media has showered Smith with the acidic criticism. It’s almost like ESPN’s Trey Wingo has coached in the NFL and won more than two of every three games. From an analytic perspective, Brian Burke at Advanced NFL Stats explained that going for it was the right call. Mike Smith probably doesn’t read those types of blogs or know that going for it gave him a 47% chance to win the game while punting left the Falcons a 42% chance. But Smith may have known that the New Orleans defense ranks last in the NFL in rush yards per attempt. And he certainly knows that our football obsessed culture loves the aggressive, down hill running game that characterizes many successful NFL offenses. So why don’t people appreciate the same aggression in play calling? No matter what the numbers say, if a team can’t make a 4th and inches against the worst rush defense in the league, it doesn’t deserve to win the game.

NFL Rankings, Week 5

Okay New England, we get it.  You’re good at football.  And St. Louis, it is likely that you’re already thinking more about the race to acquire Andrew Luck than the race to make the playoffs.  But today I’m not interested in the highs and lows of The Power Rank, I’m taking a shot at it’s sweet, juicy center.

To get a look at what truly constitutes the center of the Power Rank grouping, I used a mathematical formula for Standard Deviation, something that defines the variation from the mean (or average) in a data set.  If you’re enough of a nerd to not stick your tongue out at that definition and want to know more, you can look at Wikipedia’s explanation.

If you’re like me and most math classes made you go crossed-eyed and start drooling on yourself, all you really have to understand is that the bulk of a group (about 68%) falls within 1 standard deviation of the mean on either side, and that the bulk of the remainder (about 27%, for a total of 95% of the whole) falls within 2 standard deviations of the mean.

In other words, teams whose rating falls within 1 standard deviation of the mean (always 0.0 for the Power Rank) are all horribly mediocre.  Ok, that’s my inner pessimist coming out.  A more optimistic view for Eagles and Falcons fans might be to say that they are “on the bubble” when it comes to elite NFL teams (or horrible NFL teams, but we won’t dwell on that).  On the other hand, teams that exceed 2 standard deviations of distance from the mean are truly in a class of their own, either high class or low class depending on which side of the curve they are on.

That’s about as much explaining as I can do, although further questions about the mechanics of this process can be emailed to Ed, who will no doubt be able to give you a thorough explanation of the math that goes into this process.  For my part, I just plug numbers into a free online calculation program and analyze the output.  Ah… sweet, sweet technology.

On to football.

The standard deviation in this week’s power rank is 5.49.  That means that the bulk of teams will fall between 5.49 and -5.49, almost all teams will fall between 10.98 and -10.98, and teams beyond those ratings are truly special.

Congratulations to the Patriots (#1, 15.79) and the Packers (#2, 11.31) for pushing the limits and existing beyond the norm.  Perhaps even more congratulations are deserved by St. Louis (#32, -9.89) for not exceeding the norm…

Very few teams fall between the first and second standard deviations.  On the high side only Baltimore, Detroit, and New Orleans (by a hair) make the grade as especially good teams, whereas on the low end Denver, Arizona, Cleveland, Kansas City, Seattle, and St. Louis all currently qualify as truly not very good teams.

That leaves the other 21 teams in the true statistical middle of the road.  Being in the middle isn’t all that bad, as you are supposedly as close to the top as you are to the bottom.  This is great news for 2010’s weekly bottom dweller Carolina, who finds themselves just within the boundaries of that first standard deviation, but not great news for teams hoping to return strong and make another playoff run like Pittsburgh, Atlanta, or Philadelphia.  Most importantly for these middling teams, their current ratings are not a death warrant for the season, they have no cause for alarm and no need whatsoever to join in the chase for the Andrew Luck Sweepstakes.

A few things to consider for these middle teams:

1.  The current standard deviation is almost 1 point bigger than it was at the end of last year when it ended up at 4.59.

2.  At the end of last season The Power Rank was a little more balanced with one team above 2 standard deviations (New England) and one team below (Carolina).  Currently the two teams exceeding 2 standard deviations from the mean are both on the high side. Most likely, either New England or Green Bay will fall back into the sweet center during the season.

3.  When one (or both) of the juggernauts fall they will bring that standard deviation down with them.  This will cut some teams out of of the running for average status (look out Indianapolis, Jacksonville, and Carolina!) but on the upside a few teams may be thrust into greatness without needing to earn it (it may finally be the year for Houston or San Diego to go all the way).

4.  When the standard deviation shrinks a couple struggling teams may also become hopeless.  But come on, we are only one quarter of the way through the season!  Now is the time for Vikings fans to Ponder over whether or not they can finish out 12-4, Miami fans to Marshall their courage, and Colts fans to…  oh, who am I kidding?  Without Manning they have lost their identity…  they should focus on battling St. Louis and Kansas City in the race for the #1 draft pick in 2012.

Homefield Advantage in the NFL

It’s a nebulous topic.  Whether it’s Our House, The 12th Man, or any other name homefield advantage is an intangible that’s often invoked in football.

This season I attempted to use the Power Rank’s neutral site predictive capability and account for home field advantage…  and failed.  I added an arbitrary three points for the home team, a practice that is relatively common when setting a betting line, but a practice that is hardly scientific.

Rather than develop a complex mathematical matrix to divine the true value of the homefield advantage (I’m just not that smart…  I’ll let Ed work on that!) I decided to poke back into the recent history of the NFL to see is homefield advantage is a truly intangible myth or if it is a real and tangible aspect of the game which might one day be quantifiable.

I gathered data from NFL.com for the years 2002-2010, the only years that represent the current 32 team configuration of the league.

The first thing I wanted to look at was regular season performance.

Since 2002 home teams have won over 57% of the time, while road teams have won only about 43% of the time.  That’s a fairly strong indication that homefield advantage is tangible and meaningful, especially since every year has produced winning records for the home team.  The worst year for home teams since 2002 was 2006, when home teams won barely more than 53% of the time.

There’s a lot that goes into why playing at home is advantageous, from the comfort of your own familiar locker room to the jet lag (or lack thereof) of a coast-to-coast trip to field conditions.  One of the biggest and most obvious advantages is the crowd noise produced by a home team’s fans.  I wondered if this factor would increase the homefield advantage during the playoffs, when fans are going to be louder and more interested in every play of each game.

Here are the results for homefield advantage in the playoffs since 2002, with 2010 incomplete (and not counted):

This time there’s an even stronger correlation between home team and victory in the final win percentage, but the playoffs have special conditions that must be considered before jumping to the conclusion that the correlation is in fact stronger.  First of all, in the regular season the home team is more or less random, whereas in the postseason the home team is determined by the strength of their regular season finish…  usually.

In most cases homefield advantage in the playoffs is awarded to the team with the best record (or by tiebreakers if they had the same record) but this is not always the case.  Division winners are awarded home field advantage over wild card teams regardless of record.  That’s why the 11-5 Saints visited the 7-9 Seahawks, the 10-6 Packers visited the 10-6 Eagles (who they had beat on tiebreakers), the 12-4 Ravens visited the 10-6 Chiefs, and the 11-5 Jets visited the 10-6 Colts last week.

So in the wild card round, you have teams with better records visiting arguably worse teams that won their division.  The results from these four games last week?  A 1-3 record for home teams, with the Seahawks pulling of a somewhat miraculous win over the Saints.

So I also broke down the records of wild card games by homefield:

Not only is this correlation weaker than the homefield advantage in the regular season, its also generally weak.  52.8% versus 47.2% doesn’t create insurmountable odds.  In fact, the odds for an away team to win in the wild card round are about equal to the odds of beating the house on a casino Roulette wheel (with 0 and 00 spaces).

So what happens in the divisional and conference championship rounds when homefield advantage almost always goes to the team with a better record?

Now the correlation is at its strongest, but again the home team is already coming in favored since they usually have a better record, especially in the championship round when the home team always has the better record.

Does this just mean that the better team is winning?  I don’t think so.  The correlations here are significantly larger than the correlation in the regular season, and as all football fans know, the best team doesn’t always show up and win.  I’d attribute the correlation in the later playoff rounds to a combination of the two:  a better team playing at home has a very significantly better chance of winning in the playoffs.

So what does that mean for this week?  All of this week’s match ups feature a weaker team visiting a stronger team.  This is the kind of correlation we see in the conference championship round of the playoffs, about a 69% chance for the home team to win versus 31% for the away team.

Seattle losing to Chicago and New York losing to New England seem like safe bets this week by conventional wisdom, but the other two games are less certain.  Baltimore finished with the same record as Pittsburgh and lost the division on tiebreakers.  The  Power Rank’s #2 team Green Bay visit the Falcons, who needed a few lucky breaks to win at home against the Packers in week 12 this season.

If one of these potential upsets occurs, the record for better teams playing at home this week will be 0.750, close to the expected 0.688 correlation that is shown in the conference championship rounds of the last eight playoffs.

So it seems that homefield advantage is certainly tangible, and is particularly strong when it favors an already superior team (according to record) in the playoffs.

NFL Rankings, Week 14

In the immortal words of Leonard Nimoy:  I am about to boldly go where The Power Rank’s predictive capability has never gone before.

OK.  So that might be a slight misquote, but I’m sure if the NFL were popular on Vulcan he very well might have said it.  After all, how could Spock resist the logic of The Power Rank algorithm?

A few weeks ago, I discussed playoff predictions and how The Power Rank’s best teams didn’t quite match up with the current playoff scenario at the time, in a very incomplete season.  This week I’ve used The Power Rank’s week 14 ratings to project the victors of all games in the final three weeks of the season and calculated who will make the playoffs based on those projections.

One important modification had to be made, however, as The Power Rank’s ratings only account for a game in a neutral location.  A common practice for football bettors is to give an automatic three points to the home team to compensate for the home field advantage.  I used that convenient number to do the same with The Power Rank’s ratings when projecting the outcome of the remaining games in the season.

This three point home field bonus was surprisingly not a factor in most of the games.  Instances where it did change the outcome of a game were generally very good match ups that will certainly be big games in the upcoming weeks.

Home Field Upset Number One – Bears (#12) over Jets (#10) in week 16.  A battle between two of the NFL’s nastiest defenses fighting for a playoff spot in late December…  it could be the tag line for a movie.

Home Field Upset Number Two – Rams (#25) over Chiefs (#16) in week 15.  The Rams make a huge jump through that tightly packed middle to beat cross-state rivals.  If this prediction is correct it locks up the Ram’s playoff spot and shuts Kansas City out.

Home Field Upset Number Three – Giants (#14) over Eagles (#6) in week 15.  This one is huge.  With the three point bonus, New York edges out Philly by a mere .08 points.  If this tiniest of margins helps sway the game in favor of the Giants it will not only edge Green Bay (#3) out of the playoffs but also make a tie for division winner between the Eagles and Giants in overall record, head-to-head record, and division record.  Even though both teams make the playoffs either way, a Giants win could bring the seeding into question.

Home Field Upset Number Four – Buccaneers (#21) over Lions (#19) in week 15.  This…  is not an exciting game.  The Lions proved last week against the Packers that they could be potent playoff spoilers, but The Power Rank suggests that the Lions won’t thaw in time to win when visiting sunny Tampa Bay.  This win helps Tampa eventually climb to 10-6, but they still fall short of the playoffs unless…

Non-Upset Big Game Number One – Buccaneers (#21) at New Orleans (#8) in week 17.  The Power Rank predicts a solid victory for the Saints, but consider this a March Madness style play-in game.  The Power Rank predicts both NFC South teams will enter this game at 10-5, meaning the winner will move on and the losers will go home.  If both teams do show up tied expect a battle.

Check out the predictions for Week 15 here.

On to the winners…

The AFC doesn’t have many surprises as the top ranked teams finish strong and secure their playoff spots.

The NFC is a bit more jumbled.  #3 ranked Green Bay feels the sting of five losses by a total of 16 points and doesn’t make it.  Making Packer and Buccaneer fans especially angry is St. Louis limping in with the NFC West title and an 8-8 record.

So, 10  of the Power Rank’s top 12 are expected to make the cut.  The exceptions are Green Bay (#3) and Cleveland (#11), with the Giants (#14) and St. Louis (#25) taking their place instead.

1. New England, 11-2, 9.29
2. Pittsburgh, 10-3, 5.98
3. Green Bay, 8-5, 5.69
4. Baltimore, 9-4, 5.22
5. Atlanta, 11-2, 4.78
6. Philadelphia, 9-4, 4.12
7. San Diego, 7-6, 4.09
8. New Orleans, 10-3, 3.03
9. Indianapolis, 7-6, 2.87
10. New York Jets, 9-4, 1.83
11. Cleveland, 5-8, 1.53
12. Chicago, 9-4, 1.50
13. Tennessee, 5-8, 1.42
14. New York Giants, 9-4, 1.20
15. Miami, 7-6, 1.07
16. Kansas City, 8-5, -0.96
17. Houston, 5-8, -1.12
18. Oakland, 6-7, -1.15
19. Detroit, 3-10, -1.19
20. Dallas, 4-9, -1.22
21. Tampa Bay, 8-5, -1.52
22. Jacksonville, 8-5, -1.71
23. Buffalo, 3-10, -2.43
24. Minnesota, 5-8, -2.52
25. St. Louis, 6-7, -2.63
26. Cincinnati, 2-11, -3.03
27. Washington, 5-8, -3.23
28. San Francisco, 5-8, -3.59
29. Seattle, 6-7, -4.38
30. Denver, 3-10, -4.52
31. Arizona, 4-9, -7.01
32. Carolina, 1-12, -11.39