Eagles vs. Saints: The Day After

Unfortunate ending to a really entertaining season, but can’t say it was that surprising.  In fact, the only surprise is in how little blame there is to be placed (as long as you’re not a WIP lunatic).  The fact is, the Eagles played a relatively good game yesterday.  The problem is, so did the Saints.  Clearly both teams were very evenly matched and the Saints just happened to be winning when the music stopped.  Tough break, but don’t overreact.  Picking it apart a bit:

– A lot of people on Alex Henery’s case, which is a little unfair.  I’m certainly not a Henery fan (and think he’ll have to compete for a job next year), but we can’t pretend that a 48 yard kick in 20 degree weather is an easy shot.  For example, look at this chart from an article at AdvancedNFLStats.com from 2012:

Screen Shot 2014-01-05 at 2.23.54 PM

I’m not exactly sure what the data set is, but assuming it’s reasonable, that means the kick was, at best, a roughly 50/50 proposition.  If anything, Chip might deserve a bit more blame for kicking it instead of going for it.

The lack of touchbacks hurt as well, but again, kicking in 20 degrees is difficult, and I’m not sure how many other kickers would have done much better (definitely some, but my guess is not a lot).

– Nick Foles took a bad sack just before the previously mentioned FG attempt.  Again, though, it’s pretty hard to be mad at that.  He’s a young player who made a mistake due to inexperience.  It happens.  He also looked like he missed a few opportunities downfield, but I can’t say that with much confidence without an All-22 review.  Regardless, when you play a low-risk game, you’re going to miss some of those shots.  That’s part of the trade-off for not throwing any interceptions.

– The kick-coverage killed them at the end of the game.  The Eagles were one of the weaker STs units in the league this year.  So not surprise there.  Once again, it’s hard to blame the team.  The roster just isn’t that deep, which we’ve known for a while.  That hurts STs.  Another draft or two should fix that, it just wasn’t possible to do in one offseason.

– Roc Carmichael was victimized on a key 3rd and 12, and had a terrible mistake in punt coverage (when he kicked the ball into the End Zone).  But….it’s ROC CARMICHAEL!   This gets back to team depth.  If the roster was deeper, Carmichael wouldn’t have been on the field, and maybe those plays get made.  CB depth has to be near the top of the list for offseason needs, so I expect that to be remedied as well.

– The offense was very inconsistent, and downright nonexistent early on.  The Saints, though, were the 10th ranked defense by DVOA coming into the game.  They were missing Kenny Vaccaro, but the fact is, that was a good defense.  Putting up 24 points isn’t a great performance, but it’s also not bad.  The Saints allowed more than 24 points just four times this year.  

– Riley Cooper had a bad drop.  No real defense here, other than to say that all WRs drop passes sometimes.  Also, the Eagles still took the lead after that play.  It was a bad mistake, but no team is perfect (the Saints certainly had some similar mistakes as well).

There were other issues as well, but the overall message is: the game unfolded pretty much as we expected.  I’ll soon start going through the season in more detail and we can talk about what improvements should be made (I’ve got some different ideas than most), but for now, you should feel encouraged, despite the loss.  Here:

– Your 2nd year, 6’5″ Quarterback just and one of the greatest seasons (albeit abbreviated) in the history of the league.

– You have perhaps the best coach in the league (outside the untouchables like Belichick, Payton, Harbaugh).

– The rest of the division is a mess, and there’s very little chance that the Eagles don’t open as NFC East favorites next season.

– Nick Foles is 24 years old.  LeSean McCoy is 25.  Zach Ertz is 23.  Brandon Boykin is 23.  Fletcher Cox is 23. Mychal Kendricks is 23. Lane Johnson is 23.  Jason Kelce is 26.

That’s a pretty good “core”.  Add in potential contributors Bennie Logan and Earl Wolff (both 24), and I’m not sure there’s a team better positioned for the next 5-6 years than the Eagles.

Moreover, D-Jax is only 27.  So is Connor Barwin.

Lastly, Chip Kelly is only 50 (young in HC years), and just won 10 games in his first year.

Wild Card Weekend: Eagles v. Saints Pre-game Notes

Finally here. I don’t know about you, but it feels like the Dallas game was a LONG time ago. In no particular order, here are some things to think about heading into tonight’s game:

– Brian Burke from AdvancedNFLStats.com has done some research on dome teams playing in cold weather.  I won’t spoil the surprise, but it’s really good news for Eagles fans.

– I tweeted this yesterday, but since 2005, home teams that were 2.5 point favorites have won 50.6% of the time.  Combined with the variance numbers I showed you yesterday in my odds breakdown, that mean tonight really is a “anything can happen” game.  It could be a blow out for either team and it wouldn’t surprise me.

– Jimmy Graham gets a lot of attention, but you should worry more about Darren Sproles.  Graham is going to do damage, there’s almost no way around it.  However, it’s the secondary weapons we have to eliminate.  Sproles tops the list because the Eagles just don’t seem that concerned with RBs out of the backfield.  Also, I feel like I’m the only one harping on Kenny Stills.  He’s a rookie and he didn’t have that many catches this year (32), but he averaged 20 yards per reception and scored 5 TDs.  Anytime Stills is one-on-one with a safety I’ll be holding my breath.

– Lots of comments on my Blitz Theory post, some of them very good, some of them dumb as hell (at BGN, not here).  It needs work, but a lot of people have asked how I would apply it to Drew Brees.  Drew Brees is a great QB, therefore minimizing time becomes vital.  He just won’t miss many windows if he has time to throw, so sitting back in coverage is dangerous.  So don’t be upset if Davis blitzes a fair amount.  HOWEVER, one thing I didn’t discuss was TYPE of blitz.  That’s a whole different analysis.  Against Brees, I’m terrified of the CB and S blitz.  I wouldn’t use them.

The Double-A gap blitz that Davis also likes is very risky, since Brees is smart enough to diagnose it quickly and it leaves a lot of open space for him to hit.  BUT, remember that Brees is pretty short (6’0″…maybe).  That means it’s tougher for him to throw over people. If the blitzers are cognisant of that (get their hands up), the Double-A blitz may not be as bad a call as it seems.  Of course, it should be used sparingly and only when the Eagles NEED a big play.

– Keep an eye on the kickers.  This shapes up to be a close game, and in very cold weather, kicking is more difficult (especially distance).  Alex Henery has been good recently, but I still don’t trust him from beyond 40 yards.  However, the Saints haven’t exactly been consistent in that department either.  They fired their kicker (Garrett Hartley) and signed Shayne Graham in week 16.  Graham doesn’t have a cannon either.   His career long is 53 yards, though he did hit nine 50-51 yard FGs last year for the Texans (his previous season high was 4).

A side effect of both kicking games is that we’re likely to see several 4th down conversion attempts.  I just don’t see either of these guys attempting a 50 yard FG.  As unfortunate as it would be, the game might come down to which team converts (in other words…luck, well mostly).

– I’m going to keep saying it until it happens:  A surprise onside kick would be huge.  With a bad defense (Eagles) going against a very good offense (Saints), field position means relatively little.  In other words, the 25 yards you sacrifice from NOT recovering an onside kick doesn’t mean that much.  I’d gladly trade that for a close to 50/50 chance at stealing a possession.

Note: The Eagles ARE still a bad defense.  A lot of people have been arguing otherwise, but Football Outsiders has them ranked 23rd by DVOA (they finished 26th last year).  The team has been trending significant upwards (ranked 12th after week 9 I believe), but remember all of the key offensive players the Eagles haven’t had to play against due to injury.  Aaron Rodgers, Adrian Peterson, Demarco Murray, Reggie Bush….

– I’m leaving it there.  You can find all of the normal pre-game analysis elsewhere.  This game has all the ingredients for a true classic, hopefully it lives up to its potential (with an Eagles win of course).

Eagles vs. Saints: Odds Breakdown

blew it last week, missing on both the spread and O/U (very rare, at least this season). I blame Patrick Chung…but I did overlook the recency effect of the Bears game. Probably wouldn’t have effected the final pick, but may have changed the expected safety margin.

Anyway, that’s all in the past. Unfortunately, this week is difficult, for several reasons I’ll explain below. I’m assuming everyone has already read a ton of breakdowns, so I’ll keep the stat comparisons to a minimum, let’s just get the basics out of the way:

The Eagles are favored by 2.5. The Over/Under is 53.5 or 54, depending on the source.

– Eagles rank 8th overall by DVOA, the Saints rank 4th.

– The Eagles offense ranks 2nd. The Saints defense ranks 10th.

– The Eagles defuse ranks 23rd. The Saints offense ranks 5th.

– The Eagles STs rank 25th, NO ranks 24th.

– The Eagles point differential this year is +60. The Saints is +110.

Overall, the Saints have been the better team, though the only significant advantage is presented by the weakness of the Eagles defense. However, as everyone’s heard by now, the Saints offense has been MUCH better at home than on the road this year. If that’s meaningful (and not just a statistical fluke), it could go a long way towards equalizing the only significant difference in these two teams. Also, this is my favorite stat for this week (for Eagles fan’s confirmation bias):

In playoff games when the weather was 35 degrees or below, dome teams have won 3 of 25 games. – Chase Stuart

Now, let’s actually analyze this a bit.

The Spread

The following numbers show why this game is a terrible one to bet on:

NO – 14.7% (25th)

PHI – 30.1% (32)

Any guesses as to what those represent? It’s something I’ve talked about relatively recently. Maybe this will make it easier:

I’m talking about the performance Variance of each team, as measured by Football Outsiders. Put simply, these are two of the least predictable teams in the league. For projection purposes, that’s obviously a bad thing (in this case, sometimes you can benefit from high-variance). As you can see in the rough approximation I’ve drawn above, while the Saints are the slightly better team, there is a LOT of room for overlap here, and the spread is just 2.5 points.

So, I’ll make a score projection anyway, but it will warrant less confidence then usual.

Player-wise, Kenny Stills scares me a lot, as the PHI safeties don’t have the speed to stay with him. Darren Sproles does as well, because the defense has struggled to cover RBs out of the backfield. Graham will get his, but if the Saints win, it’ll be because one of those two guys (if not both) do some serious damage.

There are two games on the Saints schedule this year that stand out as good comparisons for this week. In weeks 5 and 6, the Saints played Chicago and New England, both on the road. Chicago’s defense ranks 25th, two spots below the Eagles. The Saints scored 26 points against them in a win. New England’s defense is ranked 21st, two spots higher than the Eagles. The Saints scored 27 points against them in a loss. Unfortunately, those games took place relatively early in the season. However, the Saints do not have any major injuries (though Pierre Thomas might sit out), and the team that took the field in those games is very similar to the one that will play against the Eagles.

Overall, the Saints are averaging 25.9 points per game, but just 17.75 on the road. Note, however, that those road games included contests against Seattle, Carolina, Tampa Bay, the Jets, and the Rams. Those 5 teams are all ranked in the top 12 in defensive DVOA.

As a result, I think we should put more stock into the overall average and the games against the Bears and PatriotsThat gives us a projection of 26-27 points.

Meanwhile, the Eagles are averaging 27.6 points per game. As far as key guys, I’m looking to Zach Ertz and Brent Celek. Shady should have a big game, but that’s expected. After watching the Cowboys, I’m sure the Saints will look to pressure Foles, which means he’ll need outlets. If I’m Kelly, I use the TEs to chip the DEs/LBs, then leak into the middle of the field, 5-10 yards from the line. Foles’ height and the shotgun snap should allow him to hit this area despite having defenders in his face, and both Celek and Ertz can be dangerous after the catch (though for different reasons). The normal screen game would make sense, but it’ll likely be a focus of the Saints defensive game-plan.

Looking for comparable team match-ups, the week 6 game against Tampa Bay stands out. While it was on the road, it was against the 8th ranked defense (2 spots above NO), andNick Foles was the starter at that point. In that game, the Eagles scored 31. More recently, the Eagles scored 24 points at home against Arizona, the 2nd ranked defense in the league, and 34 points at home against Detroit, a defense that ranks 4 spots below NO.

That gives us a range of 24-34. Adjusting those boundaries to account for the difference in opposing defense, we get a range of 27-31 points.

Taking the midpoints of both projections, we get a combined projection of:

Eagles 29 – New Orleans 26.5

Does that look familiar? (I swear I didn’t back into it). While 29 points is a very unlikely football score, remember that we’re more concerned with the DIFFERENCE and not the actually values. Here, it’s 2.5 points, which is exactly what the spread is.

So, to sum up the spread, we have a projection that lines up EXACTLY with the spread. We also have two very unpredictable teams.

That means, of course, that the smart play is to stay away from the game. Moreover, an Eagles win will be entertaining enough that winning money on top of it won’t mean much. Conversely, unless you’re a professional (in which case you’re likely to be less of a “fan”), there’s no way you’re betting against your team in a playoff game.

If I HAD to take a side, I’d go with the Eagles, on the off chance that there really is something substantial behind the “Drew Brees in cold weather” story. However, I don’t HAVE to do anything, so I’m passing on this one.

The Over/Under

If we add up our scoring projections, we get a total points scored range of 53 – 58 points. Depending on your source, you’re looking at a line of 53.5 – 54 points. That means the Over looks to be the SLIGHTLY better play here.


Remember the variance. Remember you’ve got a young QB (Foles) playing in his first playoff game. Remember that game-time temperatures are going to be below 20 degrees. Also note that, at home, the Eagles are just 3-5 against the O/U. On the road, the Saints are 2-6. Combined, that’s a record of 5-11.

I don’t put much stock in those things to actually shift the projection, but I DO use it to adjust the relative confidence level of the game. So I like the OVER, but it’s by a very narrow margin.

Summing Up

I hate the spread (because it looks to be a great one). I like the OVER, but by a very narrow margin. My overall recommendation would be to pass on this game completely. I just don’t see much opportunity here, and the game will be entertaining enough with out it. The line hasn’t shifted, so we can’t take advantage there, and the teams are both very unpredictable.

That’s a pretty unsatisfying recommendation, but I just can’t see a way around it. Hopefully, the Eagles will win the game and gives us another opportunity next week.

Maximizing the Kick Return Game

Time for another guest post from Jared.  For those of you who don’t know, Jared is my brother.  He’s also a U of Chicago MBA and a two-time Jeopardy! champion.   You can follow him @jaredscohen or see the original of this post at his site, linked here.  Now, his words:

Last year I put together some analysis of NFL kick returns. I was really motivated by one big question – Why do teams return kicks?

Initially, I wondered if returning kicks was even the optimal decision for teams trying to win football games. I wondered if the risks of turnovers and poor field position meant teams really should prefer a touchback to bringing the ball out of the end zone.

As a brief review, that’s not the case. Returning kicks is, on average, better for scoring points than taking a knee in the end zone as the returns leave your team with better field position. If you look at it in terms of expected points generated on kick returns vs. generated on touchbacks – the distinction is clear: (Note: this analysis relies on the concept of expected points based on field position – which I’ll assume readers have already seen and grasped)

This data comes from the first 16 weeks of this NFL season, over 2400 kicks. It’s also consistent with last year’s data.

So returning kicks is good, but think about why it’s a good idea. Although it presents better average field position, the average return nets only about four yards of position (and only two yards if the ball is brought out of the end zone relative to a risk-free touchback).

Linking back to material my brother has posted – the upside is directly tied to variance. Returning kicks is much more of a high-variance strategy.

Below – is an illustration of all returned kicks through Week 16 this year. The histogram shows the distribution of expected points.

You see the giant spike between 0.3-.04 which equates to a return between the 18 and 22 yard lines, that’s the most typical result (remember a touchback is worth 0.34 expected points). But there’s also an extremely long tail of positive performance, and these outliers can be worth a lot more (even a touchdown). Those outliers are what make kick returns worth the risks (injury, turnover), which is exactly what we mean when we talk about high-variance strategies.

A touchback has zero variance. That result is predictable and constant. But a return, that could be a whole bunch of possibilities.

OK – so let’s take the idea that returning kicks instead of taking touchbacks is a high-variance strategy as a hypothesis. Now, if that’s true, we would expect to see a couple different trends in the data. Generally, we would expect less talented teams to return kicks MORE often than their better opponents. Weaker teams should be pursuing higher variance plays in an attempt to pick up ground on those other (stronger) squads. In an example – you’d expect the Jaguars to try everything to beat the Broncos because Denver is extremely talented and playing a conventional game will leave the Jaguars at a big disadvantage. That could mean any number of things, more shots downfield, 4th down conversion attempts, surprise onside kicks, and we could expect – more kick returns.

So…is that something we actually observe in the data? Are weaker teams pursuing higher variance strategies in the form of more frequent kicks?

To test this, I went back and looked at my favorite kickoff metric – percentage of touchback eligible kicks returned. This counts the number of kicks that were returned out of the end zone as a proportion of the total number of kicks fielded in the end zone. Obviously – teams will return all kicks fielded short of the end zone, so we need to exclude these. The real decision point is whether or not teams bring balls out of the end zone – this is our true high variance strategic choice.

The data set it built off of play-by-play information, which is the best I can get. Unfortunately, there are a large number of touchback kicks where distance is not recorded and it isn’t specified whether the kick was fielded or kicked out of the end zone. After some initial eyeballing I’m confident these are kicks out the back of the end zone (Matt Prater of the Broncos had a lot of them as an example). So our set of kicks is a little smaller than you might expect. But there are still 950 kicks in our sample.

Then, I took all the NFL teams and split them into three performance tiers based on point differential. Teams with the highest point differential are members of the first tier, teams with the worst scoring differential are in the third tier. Below are the teams and their tier positions.

You can see the usual suspects in both the first and third tiers. And to me, this is where we’d expect to see the biggest change. These third tier teams – they have to do MORE to compete against first tier teams. Alternatively, first tier teams, one might argue, don’t need to take additional risk by sending their return man out of the end zone. If we look at touchback eligible kickoff return percentage across the different matchups – we can see if there’s any difference in the way teams behave. Do third tier teams return more kicks when they face off against first tier teams? Do first tier teams (who don’t need to pursue high-variance strategies) return fewer kicks?

Hmm…there’s almost no difference in return % whether the worst teams are facing other crappy teams or the best teams. That seems a little odd…as we had guessed the worse teams SHOULD be returning more kicks when they face better teams. This indicates that this doesn’t happen.

It’s also not a result of sample size, as most of these cells are large enough (80-120 observations).

As another check, I looked at touchback eligible return percentage relative to specific team talent (via point differential) on a team-by-team basis. I did this to see if there were any teams that really seemed to be demonstrating aggressive tactics at the individual level.

Again, this doesn’t appear to support our thinking that poor teams are pursuing higher variance strategies by returning more kicks. At best, it’s inconclusive. There are a couple of teams, like the Vikings, who really push the envelope – but there’s not a major correlation between team talent and return percentage (correlation is roughly -0.15)

Strange, but maybe identifying high-variance strategies before the game starts and following them blindly isn’t really what coaches of less-talented teams spend time on. Is there another way we can test our hypothesis?

Another theory is that if teams aren’t determining to return more kicks as part of pre-game strategy, maybe it’s something they pursue once they fall behind on the scoreboard. This wouldn’t even have to be exclusive to poor performing teams – any team that’s fallen behind might be more likely to run back kicks to try to break a big play to help catch up. What if we examine touchback eligible return percentage by in-game score differential?

The chart below illustrates the return percentage across a set of different score bands, ranging from down by more than 14 points to ahead by more than 14 points.

Again – there doesn’t seem to be any real connection between the scoreboard and aggressive kick return tactics. A team down by more than two touchdowns is just as likely to return a kick out of the end zone as one who is tied. If a kick return out of the end zone is indeed an aggressive play with a higher reward – teams don’t appear to be pursuing it MORE when they need to make up ground or LESS when they have a large lead. (As an aside, I absolutely cannot explain why having a small lead seems connected to a dramatic drop off in returns. I’ll chalk that up to some data wonkiness unless someone has a great insight there.)

But the broader concern remains. Shouldn’t teams which are behind or less talented need to take more chances to win? Why aren’t they doing that and bringing kicks out of the end zone?

My initial guess, though I’d welcome other speculation, is that teams the organizational structure of coaching almost inhibits something like that from happening. This comes with the obvious caveat that I’ve never coached in the NFL (so sure, Bill Belichick or someone else can dismiss all this out of hand as mom’s basement musings – but screw them). But if you’re the special teams coach of an NFL team – your work includes a thorough evaluation of your special teams and your upcoming opponent. All that work and planning becomes a little less valuable if a head coach just says – ‘Hey, I think we should return any kick we get in the end zone’

If the special teams coach is to maintain any kind of control over what his squad does – a simplistic rule like ‘run them out when we’re behind’ may not be sophisticated enough to justify all that pre-work and planning.

But that’s just a thought, based on the idea that coaches know their teams and customize approaches based on their own teams’ skills and the matchup with the opponent. Of course, when you actually look at the data, teams don’t really appear to be all that successful in managing their return game. Below is an illustration of touchback eligible return percentage, but this time charted against the average return position (i.e., return ability).

While we’d expect to see some correlation here – to show that teams with good return games return more kicks and teams with poor return teams take more touchbacks – that’s only true to the degree of a 0.2 correlation.

Some teams seem to get it – the Bills are really bad in the return game, but they rarely return kicks out of the end zone (on a relative basis – still over 50%). At the other extreme are the Vikings. The have Cordarrelle Patterson and, as such, they return kicks out of the end zone over 95% of the time!!!

On the flip side, look at Washington and St. Louis, teams with mediocre return units that run kicks out of the end zone 90% of the time. The Chiefs and Ravens seem odd as well – teams with great performance who could stand to run some more back. Now, maybe the Redskins are pursuing a high variance strategy, and maybe the Chiefs a more conservative one, but the overall results remain inconclusive.

At the end of the day, I come back to the idea of coaches and control over their special teams. For any team to read any of this and think about employing a ‘high-variance’ strategy – it really requires an admission of the role of chance in the outcome of a football game. Running every kick out of the end zone is a strategy based on the concept of inherent variability in outcome. Some returns may get stuffed, and others may go for big returns, but you can’t be sure when one or the other will happen. That view, to me, is fundamentally opposite the idea that with the right scheme and flawless execution – you can create the optimal outcome.

One of those ways of thinking supports the coach as the ultimate authority, while the other incorporates more probabilistic thinking. That gap is why I think we haven’t seen any patterns to support our hypothesis, and no clear evidence of high-variance kick return strategy consistently employed in today’s game.

Two-Factor Blitz Theory

I received some pushback from yesterday’s Billy Davis rant, so today I’m going to try to add some nuance to my explanation.  First, I want to note that while Davis bears the brunt of my criticism, he’s certainly not the only DC I disagree with on a fairly consistent basis.  Graded against everyone else, Davis is OK (for now).  However, as is usually the case, just because everyone else does something doesn’t mean we need to do the same thing.  Conventional wisdom, especially in sports, frequently lags the “optimal” strategy.

So….Defensive Strategy, and more specifically, the Blitz.

My general take on this is that the Blitz (sending more than 4 pass rushers) should be viewed as a TOOL, not a general philosophy.  I realize that in Philadelphia, that’s borderline heresy (lot of Jim Johnson fans out there).  But let me explain.

Two Factors

To complete a pass, two things must happen (generally speaking): an “open” receiver must exist, and the QB has to identify that opening (after which he presumably throws the ball there).  It’s tough to determine what constitutes an “open receiver”, so I’m going to discuss this side of things in terms of Windows.  So a passing window refers to an opportunity to place the ball where the receiver can catch, and one must exist and be identified in order to complete a pass.  Simple enough?

Also, for a QB to identify the available passing window, he must have TIME to do so.  The more time he has, the higher the odds of him seeing an existing window or of one developing.

By breaking the process down into these factors, we can see the basic trade-off in defensive strategies (against the pass).  The best of both worlds, of course, is to minimize the passing windows AND minimize the time the QB has to identify them.  That’s why DEs are so coveted.  If you can generate a strong rush (i.e. lower QB time) with just 4 d-linemen, you can use everyone else to close passing windows.  However, very few teams area able to do that on a regular basis.

More often, you have to make a choice.  You can rush an extra man (blitz), which should decrease the amount of time the QB has to see a window.  Conversely, you can rush fewer men, and use more of them to minimize the windows.

With me so far?  Good, now let’s talk a little bit about passing windows.

Passing Windows

Passing windows open and close throughout each play.  A complete pass occurs when one of them opens and the QB hits it.  To help illustrate, I’ll pick a random frame from Sunday’s game:

Screen Shot 2013-12-31 at 9.57.59 AM

Nice….Now let’s superimpose the passing window on it.  Despite the outcome of the play (Boykin game-saving interception), there was, in fact, a window to hit here for Orton.

Screen Shot 2013-12-31 at 10.02.04 AM

That’s a rough approximation, obviously, but you can see the idea.  Given such a big opening, how the hell did Orton miss?  Any guesses?

How about:  He’s not a good QB!?

That’s a little unfair (just a little), because every QB misses opportunities sometimes.  However, let’s dig a little deeper into this.

When deciding what pass-rush strategy to use, there’s perhaps no greater factor for consideration than the skill of the opposing QB.   We now have to combine the QB skill with our Window illustration from above.  Let’s visualize it like this:

Screen Shot 2013-12-31 at 10.11.23 AM

Don’t get too caught up in the relative sizes, this is far from a “to-scale” illustration.  In the middle we have the passing window.  On either side I’ve provided a visual representation of each QB’s (Peyton and Orton) accuracy.  Think of the two layers as confidence intervals; something like 70% certainty the ball will end up within the smaller red circle and 90% certainty it will end up within the outer circle’s boundaries.

Hopefully this is rather intuitive.  Now play a mental game using those images.  The green square will move across the screen from left to right.  You control the red circle, and your job is to align it with the passing window and and press go.  Think of it like aiming a rifle.

Now…which player’s range (red circles) would you rather play with?

Easy, Peyton Manning’s, because his confidence ranges are smaller, meaning there’s a smaller margin of error.  For example, let’s say you align each perfectly with the passing window:

Screen Shot 2013-12-31 at 10.19.15 AM

See the problem?  The window is smaller than Kyle Orton’s accuracy range.  Meanwhile, it the window is significantly larger than Manning’s 70% accuracy range.  The upshot, naturally, is that Manning is a lot more likely to complete this pass.  Going back to our game image above, we can visualize the pass like this, with the yellow X denoting the final placement of the ball, which was intercepted.

Screen Shot 2013-12-31 at 10.23.35 AMMoreover, we can extrapolate the idea.  In general, Peyton Manning will be able to hit smaller windows than Kyle Orton will.  Obviously, smaller windows occur more frequently than larger windows, hence Peyton Manning, by virtue of his accuracy, will have many more opportunities to complete passes than Kyle Orton.

Now pretend you’re a defensive coordinator.  Remember you have a choice to make between eliminating passing windows and minimizing time.  In this exercise, you cannot do both.  Against which player is the “window elimination” strategy more likely to work?

Easy (again), Kyle Orton.

Since Peyton Manning’s required window size is so small, eliminating them will require extremely good coverage.  More likely, you can play excellent coverage on the receivers and STILL not prevent several of these small windows from opening up.

Conversely, against Kyle Orton, things aren’t so difficult.  He needs a relatively large window.  Large windows are easier to eliminate.  You don’t have to play perfect coverage. Notice in the Boykin play, there was a relatively large are in which Orton could have complete a pass for a big gain.  Fortunately for the Eagles, Orton didn’t hit his spot.  Boykin’s coverage was far from perfect, but it didn’t need to be!

In light of that, go back you your strategy decision.  Which do you think is easier to do:

– Eliminate windows

– Minimize time

Now consider that Orton was operating out of 3-step drops for much of the night.  Then, the answer is easy.  Eliminating his passing windows is the much higher-probability play.  Note that’s the BASE strategy.  Obviously, you need to blitz every once in a while, if for no other reason than to add some unpredictability.

That’s the crux of my argument against Billy Davis’ blitzes.  He doesn’t seem to vary his usage as much as I believe he should, and he doesn’t save his blitzes for high-leverage situations.  Instead, he uses them in LOW-leverage situations, where the reward of a sack is comparatively low, especially when weighed against the odds of a big play.

Against a great QB (like Drew Brees this week), you have to be much more aggressive because it’s much more difficult to eliminate those passing windows.  Moreover, there’s another factor to discuss:

The Blitz Bonus

A very successful blitz will result in a sack.  A sack dramatically swings the odds of a turnover (punts included) in the defense’s favor.  Now, comparing opposing QBs, against which ones do you think that’s most important to do?  I’ll give you a hint, it’s not Kyle Orton.

Against a great offense or great QB (frequently one and the same), the odds of allowing a 1st down are comparatively high.  For example, according to Pro-football-reference.com, the Denver Broncos faced 93 third downs needing 5 or fewer yards for a first down.  They converted 62.4% of those.

Now compare that to a bad offense, like Baltimore (ranked 30th by Football Outsiders).  The Ravens faced 96 third downs with 5 or fewer yards to gain.  They converted just 49% of those.

As you can see, getting to 3rd and less than 5, normally not considered much of a “win” for the defense, is still good enough to get you to 50/50 against a bad offense.  Assuming each opportunity is an independent event, the odds of the Ravens converting two consecutive such third downs is just 25%.

Hopefully your mental light-bulb just turned on.  Facing a Kyle Orton-driven offense, the Eagles were looking at a team much closer to the Ravens than the Broncos.  In that situation, just preventing a big play and forcing the Cowboys to convert a string of third downs was VERY LIKELY to produce a punt.

In other words, we didn’t NEED a sack!  The odds were already in our favor.  Conversely, if we had been facing the Broncos, the risk/reward equation flips.  That team is much more likely to convert a string of third downs, meaning the defense needs to do something to increase its odds.  Getting a sack is one of the only affirmative ways to do this.  In that case, the reward of getting a sack outweighs the risk of giving up a big play.  Without the sack, you’re likely to give up a long drive anyway!

Against a bad offense, though, that’s not the case.  It’s better to sit back, eliminate passing windows, and wait for the odds to shake themselves out.  By blitzing bad QBs, you’re making a foolish grab for upside that you don’t need.  Bad QBs will struggle to hit receivers that are even marginally covered, so why make it easy for them by making those passing windows larger?

Wrapping Up

Hopefully that illuminated things a bit more clearly.   Basically, against bad QB’s, the odds are already in your favor.  The reward of a sack (or forced incompletion), and the increased odds of a punt that come with it, are NOT worth the risk of the big play. In all likelihood, a bad offense will NEED a big play in order to score.  They simply won’t be able to string together a 12 play drive with a lot of 3rd down conversions.  Hence, the goal should be to get to third down as often as possible, and let the odds take effect.

Against a great QB, though, that’s not enough.  They ARE somewhat likely to string together 3rd down conversions, especially if their short yardage situations.  Similarly, they DO NOT need a big play to sustain a drive.  In that case, the risk of giving up the big play (which is worth relatively less to a great offense than to a bad one) is worth the associated reward of a longer yardage situation (which the defense needs to push the odds in its favor).

That doesn’t mean you never blitz a bad QB or always blitz a great one.  It does mean that you’re general pass rush strategy, particularly when it comes to sending extra pass rushers, should vary greatly depending on which QB you’re playing against.  Just saying “we’re a blitzing defense”, so we’ll blitz, is a very low-level strategy.  It’s far too simplistic, and sounds a lot more like a crutch than a well-thought out, adaptable and deployable strategy.

Week 17: Eagles v. Cowboys Post-Game Notes

Well that was….agonizing.  The offense simply didn’t do its job, if it had, the game would have been a blowout.  Not going to dwell too much on it, though.  Only thing really worth investigation is whether Foles had places to throw the ball instead of taking the sacks.

For now, some quick notes:

– One of the biggest issues the past few years has been the lack of impact players on defense.  My perspective is that, in general, you can scheme to score points, but need talent to prevent them.  The Eagles haven’t had that….until now (maybe).  Mychal Kendricks played a great game, and looks to have found some measure of consistency (his biggest issue last year).  Boykin, outside of the really stupid PR penalty, also played a very good game.  The development of those two players is HUGELY important for the future of the team, especially when you consider the very real possibility (hopefully) that the team won’t be picking in the first half of the draft for a while.  Fletcher Cox didn’t make many players, but it looked like he was seeing consistent double-teams.  If that’s true, then he’s doing his job as well.

– Jason Garrett made some very poor strategic decisions, to the Eagles advantage of course.  Punting on 4th and 2 in Eagles territory is just completely indefensible, especially when you consider how good the Eagles’ offense is (despite its performance yesterday).  It’s shocking to me that coaches still do things like that, when so much work has been done to show it’s clearly the wrong move.  According to Expected Points, from AdvancedNFLStats.com, Garret gave away MORE THAN A FULL POINT with that decision.  He also struggled with more than just 4th down calls…

– The Cowboys’ biggest advantage coming into the game was on Special Teams.  Moreover, their return man, Dwayne Harris, was healthy again and among the more dangerous return men in the league.  Yet….he brought just 2 kicks out of the end zone (averaging 32.5 yards on those returns).  Another huge strategic blunder.  It doesn’t matter that the kicks were in the back of the end zone.  As an underdog, you need to (a) up the variance, and (b) leverage your strengths.  They did the complete opposite by not returning every kick.  This isn’t an isolated occurrence either.  Look at this, from Jared Cohen,

Screen Shot 2013-12-30 at 11.17.26 AM


You can see Dallas in the upper-left quadrant.  They’re above average in returns, yet attempt them far less than average.  Yes, there is some cross-causation here (it’s possible they’re above average because the only return kicks that don’t go deep into the end zone).  However, remember they were big underdogs here, with a QB that couldn’t push the ball downfield.  Maybe they should have taken a shot at giving Dwayne Harris a few shots against a poor Eagles STs unit?  Yeah…but I’m sure happy they didn’t.

Let’s just hope Jerry Jones isn’t lying when he says he’s keeping Garrett….

– Billy Davis….I’m done.  He’s at the top of the list as far as changes I’d like to see the team make.  The personnel still needs improvement, and blown coverages can’t get blamed on him, but he just doesn’t seem to have any feel for the strategic ebb and flow of the game.  He also seems to be completely ignorant of the risk/reward equation of blitzing in various situations.

The toughest part about judging coaches is that you never know if the players are actually executing what they’re told.  However, allowing the Cowboys, in a vitally important situation, to get Dez Bryant matched up one-on-one with Patrick Chung as a result of a simple, single-man pre-snap motion is absolutely ridiculous.  It shouldn’t happen. It CAN’T happen.

Also, when blitzes aren’t working, the answer is NOT to blitz more!  Here, Davis seemed to have no idea who he was playing against.  Kyle Orton, at this stage of his career especially, is a check-down, quick-read QB.  He’s not great, but if there’s a wide-open receiver, he’s going to complete the pass.  He also can’t push the ball downfield.  So why blitz?  If the QB is routinely taking 3-step drops, it doesn’t matter what blitz you call, there isn’t enough time to for it to get home.  Instead, Davis should have been happy to rush just 4 linemen and drop everyone else into coverage.  Orton’s not mobile, so the LBs are all free to man-up or drop into an underneath zone.

Against a QB with great accuracy (like Drew Brees for example), you can’t do this, because coverage is much more difficult.  Against Kyle Orton, though, the coverage doesn’t have to be perfect, he’s not that good!  He made one legitimately great throw all game (to Terrance Williams).  Other than that, his ball-placement was off, sometimes by a lot.  If that’s the case, the last thing you want to do is make things easy for him by leaving receivers uncovered (a side-effect of blitzing).

Most unfortunately, this isn’t a one-time occurrence; Davis has struggled with this all year.

– One last blitz point….it’s a high-variance strategy!  In other words, it’s something you should generally avoid if you are the favorite.  If you’re the better team, you don’t need the high-reward!  As a result, the payoff isn’t worth the associated risk.  As a significant favorite, it’s the OTHER team that should be forced to make riskier plays.

To be fair, though, I don’t think many DCs (if any) really conceptualize blitzing or general defensive strategy like this.  That’s not a good excuse for Davis though, it just means the whole profession needs some instruction.

Now some happy thoughts:

– 10 wins, a division title, a home playoff game, the league’s top rated passer, the league’s leading rusher, the most 20+ yard plays in NFL history.  As I said in the pre-game notes, this season has been a resounding success.  We’re playing with house money now.

– The Eagles went 7-1 over the second half of the season.

– Drew Brees is legitimately great, and scares me regardless of where the game is, but getting him out of the dome really is a big deal.

– The Saints are 2-3 in their last 5 games.  It’s been a very difficult stretch (losses have come against Seattle, Carolina, and St. Louis), but still.  This team isn’t quite as good as the Saints you’re used to hearing.  That said, they have a point differential of +110, nearly twice the Eagles’ mark of +60.  (My first reaction to the -2.5 line is that it’s off by a couple of points).

– Despite that, if I told you pre-season that the Eagles were a 50/50 proposition to make it to the divisional round of the playoffs, my guess is you’d have been thrilled and/or called my insane.

– Playoffs!

Week 17: Eagles vs. Cowboys Pre-Game Notes

Win or go home; the playoffs start today for the Eagles.  As I wrote in my breakdown, the Eagles are, deservedly, significant favorites and are likely to win.  However, that doesn’t mean they will. Here’s where thinking probabilistically becomes difficult for many fans and commentators.

According to Vegas, if this game was played a very large number of times, we would expect the Eagles to win about 70% of the time.  That’s a LOT.  Moreover, I think the line is too low.  At my line, I’ve got the Eagles between 75-83%.  Very encouraging, but it raises an interesting question:

If the Eagles lose, did they “choke”?

Let’s assume for a moment that the Eagles do lose tonight.  The low-level analysis will involve “choking” and talk about things like cracking under the pressure or Chip Kelly not being ready for such a big game.  Mostly, it will revolve around one supposed fact, that the Eagles SHOULD win this game.   Read that again:

The Eagles SHOULD win this game.

It sounds right, but it’s complete bullshit.  That’s not how the sport (or the probabilities the sport is based on) works.  The correct way to say it is that, ex-ante, we know that the Eagles are LIKELY to win.  The problem with “should” is that it implies a level of control that the team simply doesn’t have, regardless of what generic sportswriters would have you believe.

Let’s use an analogy.  Imagine you’re playing poker (Texas Hold ‘Em).  You’re heads up, looking at the river.  There are no more strategic moves to be made, the outcome of the hand depends entirely on which card comes out.  Of all the cards remaining in the deck, 75% of them will result in a Win, 25% a loss.

If a Loss card comes out, did you “choke”?  Similarly, before the card is drawn, “should” you win?

Of course not, that’s ridiculous.  The fact is, the entire strategy of Poker (and many games/sports in general) is to shift the odds in your favor as much as possible (and maximize the expected payout when you do).  Unfortunately, that’s all you’re doing, shifting the odds.  As anyone who truly understands what that means knows, even after you’ve shifted the odds, there is still a chance for a loss.  In Poker, it’s sometimes called a Bad Beat.

Circling back to the game tonight, if the Eagles lose, it may just be a Bad Beat.  The Eagles are the better team, but if they played tonight’s game a large number of times, they’d STILL LOSE a decent percentage of the time (30% according to the spread).  Just as the Eagles MUST win a large majority of the games if it played a large series, they also MUST lose as well.  Unfortunately (when you’re a favorite), you don’t get a series, you get one game.

The ball takes lucky/unlucky bounces.  The refs don’t see everything correctly.  Players will have bad games, coaches will have bad games.  They are not robots, their performance varies.  If those bad games coincidentally happen to occur when the stakes are high, the knee-jerk reaction is to say the player/coach “choked”.  Or to somehow imply that the stakes themselves forced them into a sub-optimal performance.  I’m not ruling this out.  It’s possible, and it may even be probable (at the extreme margins).  However, it’s much more likely that they simply caught a Bad Beat.

As anyone who plays poker knows, when that happens, the “right” thing to do is to shake your head and check your calculations.  If they were correct, you don’t do anything different the next time (unless you really did screw up), even though the results this time were bad.  Process, not outcome.

Now, a few actual notes:

– The Eagles are 7 point favorites. E = R ((60 – T) / 60) + C.  That means, at least to start, they should be playing a relatively low-variance game.  Over any stretch of time, we expect the Eagles to outplay the Cowboys.  That puts the onus on Dallas to change the conditions.  Note though, that at 7 points, all that would take is an early TD from Dallas.

– Don’t let Dez Bryant beat you.  He’s the only elite weapon the Cowboys have.  Demarco Murray is having a good year, but if the Eagles offense performs anywhere close to expectations, Murray isn’t going to be able to keep the Cowboys in the game.

– Don’t get blitz-happy.  A frequent reaction to a back-up QB is to blitz him.  Yes, getting pressure on Orton is important, but when you blitz, you actually make it EASIER for receivers to get open, you just (hopefully) diminish the time the QB has to make that decision.  If I were calling the game, I’d want to see if Orton can move the ball against the base defense before dialing up an blitzes.  Remember, blitzing is a high-variance move.  If you’re a big favorite, you should blitz sparingly.

– Don’t get sloppy.  Penalties and turnovers can equalize a skill-advantage pretty quickly.  There’s no reason to believe either will be a problem, but that doesn’t mean the players shouldn’t be reminded to play under control (Cary Williams especially).  The Eagles have averaged 53.4 penalty yards per game this season, Dallas averages 57.5.    Similarly, both teams have averaged +0.7 turnovers per game, which is 4th best in the league (7-way tie).

– Watch out for “David” strategies.  We’ve looked at these from the underdog’s perspective, but since Dallas is in that position tonight, it’s a good chance to view things from the other perspective.  So, watch out for surprise-onside kicks or fake punts.  Expect a few 4th down plays.  Prepare to be blitzed.  I don’t think Garrett has the balls (or brains) to fully deploy these strategies, but that doesn’t mean we won’t see one or two instances. They’re high-risk/high-reward; the Eagles really want to focus on that high-risk part.

– Enjoy.  This has been a lot of fun, and regardless of what happens, Eagles fans should be pretty excited about the Chip Kelly era.  The team has already met my expectations (surpassed them in some respects), so it’d be silly to consider the season anything less than a great success, no matter what the outcome of tonight’s game is.

That said, it’s Dallas, the Eagles are the better team, and it’s for a playoff spot.  I think the Eagles roll.