Interceptions- Where Are They Thrown?

I've been racking my brain trying to find a pattern as to where intercepted passes are most commonly thrown. Are they more often thrown to one side of the field as opposed to the other, more often down the middle, to the sidelines? A lot of questions, all meant to identify if a quarterback's target and location patterns could tell us more about why he throws so many interceptions.

My first theory: Quarterbacks who throw far more towards one side of the field than to the other become predictable, and thus, intercepted more often.

To examine this theory, I looked at the 2007 statistics of all quarterbacks and broke up the distribution of their pass attempts. Luckily, ESPN.com provides a breakdown of left sideline, left, right sideline, right, and middle. More frequently intercepted quarterbacks should have a more lopsided distribution from one side to the other. However, nothing really came of this. Regardless of whether the quarterback is extremely lopsided or even-handed to both sides of the field, the equity of distribution has no relationship to his interception rate.

For the record, the most even handed QB's are:
Philip Rivers, Drew Brees, Peyton Manning, Carson Palmer, Derek Anderson.
and, in case you're interested, the guys with a favorite side are:
Matt Hasselbeck (23% more to the right), Brett Favre (19% more to the right), Rex Grossman and Marc Bulger (18% each more to the right), and Tarvaris Jackson (13% more to the right).

My second theory: QB's who throw more passes to the middle of the field will be picked off less.

A QB who throws to the middle of the field will theoretically force the defensive backs away from playing only to one side and will require them to spread out. Furthermore, a quarterback who throws a lot to the middle likely has great confidence (either in himself or in his receivers), as opposed to a quarterback who dumps off or throws to the side a lot.

This theory yielded mild support. There is a significant, albeit modest relationship between the percentage of times a QB throws over the middle and the amount of times he's intercepted. Those who do it more often are actually picked off less, although the difference is not tremendous.

The five biggest up-the-middle gunslingers:
Brett Favre (19%), Jeff Garcia (17%), Kyle Boller (17%), Drew Brees (16%), Damon Huard (16%)

The five who rarely go up the middle:

Rex Grossman (9%), Carson Palmer (9%), Tarvaris Jackson (10%), Jason Campbell (10%), Marc Bulger (10%)

My third theory: QB's who throw more to the sidelines are more likely to get picked off.

This theory was more what researchers call an exploratory research question, or less euphemistically, a hunch only modestly based on evidence. I figured, hey, maybe if those who go up the middle are picked off less, those who go straight for the sidelines are picked off more. Remember, there are other areas aside from up the middle and the sideline. The sideline is the three-yard area near the sideline. The middle is inside the hashmarks. so, anywhere outside that range qualifies as left non-sideline or right non-sideline.

Anyway, this theory came up empty. There is no relationship between the percentage of sideline passes and interception rate.



Finally, I started thinking...I'm still sold on the idea that predictability will lead to higher interception rate. But it seems that interceptions have no relationship to how predictable a QB is related to where he'll throw the ball to. That begged the question- What if a QB is predicatble about who he throws the ball to?

Whether a receiver is lined up in the slot, wide right, wide left, some QB's simply have a favorite target, regardless of where he is lined up. Sometimes, though, the quarterback likes the target so much, that the defense can anticipate the two hooking up, leading to higher interception rates.

Eureka!

Final theory: The higher proportion of passes going to the team's leading receiver, the higher that quarterback's interception rate will be.

This theory checks out. There is a robust 0.36 correlation between the percentage of passes thrown to a team's leading receiver and the quarterback's interception rate.

Last year, four receivers were thrown more than 30% of their team's passes. Those men were Baltimore's Derrick Mason, Cincy's TJ Houshmandzadeh, Denver's Brandon Marshall, and KC's Tony Gonzalez. The QB's on three of those teams were veritable pick machines, with Kyle Boller, Carson Palmer, and Damon Huard each having an interception rate of over 3.5%, which is very high.

So, it appears that an over-reliance on a favorite target is a large hindrance to an offense. This should be kept in mind when evaluating how good a QB is at spreading around the ball, and thus, the defense.

Is Week One a Bellwether for the Rest of the Season? Part II

In Part II of this series, I look at whether or not you can tell how a running back will do on the year based on his Week One performance. Last week, we discovered that you can project much of a quarterback's season based on his opening week. Is the same true for running backs?

In a word, no. A running back's yardage opening day only has a 0.39 correlation with his per game average on the year. This correlation is not negligible, but it indicates that simply looking at a running back's performance opening day will not tell you all that much about his performance over the course of the year. Quarterbacks' QB rating, by contrast, has a 0.71 correlation with their overall year performance.

Another way to look at how unreliable opening week numbers are is by examining the degree to which that first game's numbers deviate from the average. On average, running backs' first game performances last year were 20.8 yards away from what their per game average ended up being. Some noteworthy examples: LaDainian Tomlinson- Week 1: 25 yards. Season average: 92.1 yards. Joseph Addai- Week 1: 118 yards. Season average: 71.5 yards. Jamal Lewis- Week 1: 62 yards. Season average: 89.6 yards.

What accounts for this phenomenon? Running back carries are far more vulnerable to strategy changes than are quarterback stats. A new running back could start performing well, and you don't have to bench the starter in order to make room. You simply give the new guy more carries. If a running back gets a minor injury, another running back can give him rest time. If a running back is slumping, his carries may decrease for a couple of games, only to be increased again later. In other words, the life of a running back has many ebbs and flows throughout the course of the year, whereas statistics demonstrate that a quarterback's season is more consistent.

Is Week One a Bellwether for the Rest of the Season? Part I

Welcome to a multi-part discussion that will take place this week on the importance of Week 1 in projecting a player's performance for the entire year. Today's topic: Quarterbacks.

First off, how much of an indicator is a quarterback's Week 1 performance with how he'll do the rest of the year? Well, actually, it says quite a lot. Over the past 3 seasons, a quarterback's opening day QB Rating has a very robust 0.71 correlation with his season rating. Therefore, a quarterback's opening day performance will generally go a long way in telling you what kind of year he'll have. This rule is not written in stone- Donovan McNabb and Brett Favre each had QB ratings over 89.0 last year after having opening day performances below 61.0. These exceptions aside, however, the numbers are compelling.

How about if a quarterback has an unbelievable opening day? Should you expect those unbelievable numbers to keep up? Simply put, no. More quarterback ratings of 100.00 or over are achieved in Week 1 of a season than in any other week. Overall, Week 1 is the best quarterbacking week of the year. Thus, outstanding opening numbers will almost assuredly not keep up their pace. In the past 3 years, quarterbacks who had a 100+ QB rating on Opening Week finished the year with a QB rating of over 90.0 only 50% of the time. However, while those quarterbacks' numbers did go down, they didn't usually drop too far. A quarterback who starts the year with a 100+ QB rating has a 79% probability of finishing the year with a top 10 QB rating.

As for bad opening day performances, the news is not good. Last year alone, seven quarterbacks had opening day performances with a QB rating under 60.0. A grand total of one of them finished the season with a QB rating above 80.0, and the average QB rating amongst them was 75.2. Hardly the stuff of legends. The names of those luminaries, Favre excluded? Matt Leinart, JP Losman, Rex Grossman, Damon Huard, Vince Young, Jason Campbell.

Now, quarterbacks do improve over their careers. They learn the systems and develop as players. However, the noticeable change in a quarterback's performance comes during the next season, not over the course of a season. Analysts may say otherwise, but the numbers don't lie.

So, whose opening day may be a signal of things to come?

First, the 100+ club for Week 1:
Ben Roethlisberger= 147.0
Jay Cutler= 137.3
Donovan McNabb= 131.0
Brett Favre= 125.9
Phillip Rivers= 125.1
Drew Brees= 124.9
Matt Cassel= 116.0
Aaron Rodgers= 115.5
JaMarcus Russell= 111.1
Tony Romo= 103.6
Jon Kitna= 103.1

Keep in mind the defenses that each quarterback played against, but the numbers still tell us something.

And those unfortunate souls that had less than 60.0 QB rating this week...

Tarvaris Jackson= 59.0
Matt Hasselbeck= 53.9
Vince Young= 45.6
Carson Palmer= 35.3

That number is actually a bit too typical of Jackson. He is the primary reason that I didn't pick Minnesota as a true contender this year. You simply cannot have that much uncertainty at quarterback.

Well, let's see how the rest of the season plays out. Next post, we'll cover running backs...

10 Unsung Players who Could Impact Their New Teams

Everybody's been talking about Favre, Jason Taylor, Jeremy Shockey and the like changing teams and having potential impacts in 2008. But there are a lot of other players who changed teams this year who are getting the same attention. Some of them could have huge impacts on their teams and influence the playoff picture. Based on the principles of Football Know-it-All, here are ten men flying under the radar who could help their teams this year:

1. Shaun Rogers, NT, Cleveland Browns- With Cleveland’s DLI a meager 20.1 last year, this mammoth All-Pro end-turned-nose tackle could be just what the Browns ordered in their conversion to a 3-4. With help from fellow Browns newbie Corey Williams at left end, Rogers could anchor a D-Line that propels the Cleveland defense to heights only its offense reached last year. Rogers could very well hold the key to an AFC North title for Cleveland.

2. Kawika Mitchell, OLB, Buffalo Bills- He is a tackling machine, and with MLB now a more solid position in Buffalo with Paul Posluszny’s return, Mitchell’s presence could help the Bills reduce the amount of Side Yards that elite runners usually run up against them.

3. Antwan Odom, DE, Cincinnati Bengals- Observers have been waiting for the Bengals defense to develop under supposed guru Marvin Lewis. After 5 years, Lewis may finally have a pass rusher to at least make his defense respectable. Odom racked up 8 sacks last year and pressured the quarterback frequently. With rookie LB Keith Rivers, the Bengals may not have an elite defense, but perhaps they can move to the middle of the pack.

4. Jerry Porter, WR, Jacksonville Jaguars- He may have the reputation of a malcontent, but especially with the underachieving Matt Jones gone, it is crucial for David Garrard to have a big target. Porter averaged 16.1 Yards/Catch last year. As mentioned in previous posts, Long Pass Plays have a 0.75 correlation with winning percentage. Receivers than can spread the field help the offense substantially, and the Jaguars may have gotten a bargain in Porter.

5. Chris Myers, C, Houston Texans- Myers centered a Denver O-Line that is famous for making big holes for running backs, and that could come in handy for rookie Steve Slaton and vet Ahman Green.

6. Gibril Wilson, SS, Oakland Raiders- One of the leaders in the NFL among DB’s in solo tackles. This means that Wilson is excellent at taking down ball carriers in the flat and not allowing them to gain extra yards while help arrives. In case the linebacker corps does not improve as projected, Wilson’s tackling ability will be what keeps the Raiders from giving up as many big plays as they did last year.

7. Jeff Faine, C, Tampa Bay Buccaneers- Faine was a highly sought-after center from New Orleans, and an emerging Ernest Graham will thank him for coming to Tampa. However, Faine’s strength is in picking up the blitzes up the middle, and that skill will be especially crucial with a 38-year-old Jeff Garcia in the pocket.

8. Muhsin Muhammed, WR, Carolina Panthers- Bringing Muhammed back returns that possession receiver to pair with Steve Smith and really opens up the passing game. Also, keep an eye on 2nd year man Dwayne Jarrett, the lanky big-play wideout from USC who got off to a slow start in 2007 but may emerge.

9. Randall Gay, CB, New Orleans Saints- A lot of the attention went to the acquisitions of Jonathan Vilma and Jeremy Shockey, but Gay may be just as important. In the past two years, Gay only allowed a 100-yard receiving game twice. With Mike McKenzie aging, Gay may be covering #1 receivers before long.

10. Justin Smith, DE, San Francisco 49ers- Smith can get to the quarterback, and he also gets a large amount of tackles on run plays. He is so fast, he can move laterally and seriously reduce the Side Yards of many running backs. However, he can just as easily converge on the middle to clog up the guard and tackle running lanes. Also capable of playing OLB, Smith could almost single-handedly bring the Niners’ defense into respectability.

16 Predictions for 2008

*I love predictions. They are often so wrong, and you get to look back on them after the season and mock those silly enough to make them. That said, I invite you to keep this post and remind me in February how I did. If I get more than 10 right, I deserve some sort of prize. If not, I guess I deserve whatever messages you'd like to send me.*

1. The Minnesota Vikings will have the NFL’s best defense. The Viking D-Line was already the best run-stopping group in the league last year. With the addition of Jared Allen, this unit will get to the quarterback more, as well. Football know-it-All, as you know, puts a lot of emphasis on D-Line performance. Chad Greenway and EJ Henderson are underappreciated linebackers who make tackles all over the field. The Vikes updated their safety corps with a solid Madieu Williams, and Cedric Griffin is entering prime age.

2. A new running power will emerge in Carolina- The Panthers drafted Jeff Otah in the first round, and he will allow Jordan Gross to move back to the left side. This can give Carolina a top-tier pair of tackles. Combine that with their other top draft pick Jonathan Stewart, who will now team with the criminally overlooked DeAngelo Williams. As discussed on this blog, tandem running is crucial in today’s NFL, and this looks to be a potent 1-2 punch.

3. The Buffalo Bills will have a resurgent defense. In the linebacker corps, Paul Pozlusny was having a great start to his rookie season, with 25 tackles in 2.5 games before a season-ending injury. Plus, Kawika Mitchell, who gathered over 50 tackles in the second half of 2007, joins the squad. Marcus Stroud should improve a run defense that was porous last year, plus take double-teams away from Aaron Schobel. If Leodis McKelvin plays even close to expectations, he can give the Bills a good second cornerback.

4. The fight for the NFC East crown will be between the Eagles and the Cowboys. The Cowboys add Pacman to a crew that already excelled in virtually all categories. Plus, their tandem of Marion Barber and Felix Jones may be really special. The Eagles, meantime, look to dominate on the lines, improving on both rushing and pass defense.

5. Philly’s lack of a big-play receiver gives the edge to the Cowboys. This dearth of a playmaker to stretch the field has been evident for many years, with the exception of TO. There is still nobody there to help out, unless undersized rookie DeSean Jackson can become an instant phenom.

6. David Garrard will solidify himself as an elite quarterback. With a big-play target upgrade in Jerry Porter in for Matt Jones, Garrard will have an extra weapon. Plus, Marcedes Lewis is entering his third year, a year where receivers and tight ends often significantly improve statistically. Plus, Garrard’s key stats, completion percentage and TD/INT ratio demonstrate discipline that often leads to maturation rather than regression.

7. Brett Favre is in for a rude awakening. Favre owed a good portion of his resurgent year to a couple of factors. First, the receiving corps led the league in YAC and had very few drops. Also, the offensive line was superb, creating a fantastic running game and letting Favre hit the turf a conference-low 15 times. The Jets are weak in all of those categories. The offensive line is not as upgraded as some think. Allan Faneca turns 32 this year, and Damien Woody is not a natural tackle. Plus, the Jets receivers won’t bail Favre out as much as Jennings and Driver did.

8. The Seahawks will get beaten this year by…jet lag? Mike Sando at ESPN.com once mentioned how much more difficult it is for West Coast teams to travel east than vice-versa. Statistical evidence backs that up. Over the past five years, West Coast teams have played significantly worse when travelling to the east coast than East Coast teams heading west. Seattle this year has the bad fortune of playing both the AFC and NFC East division. Their winning percentage in such games is dismally below their norm, and they now have four of them to play this year. They could be a long-shot to finish .500. Hey, they may still win their division.

9. The New Orleans Saints will return to NFC contention. One strength that made New Orleans so good in 2006 was the mileage that they got out of Reggie Bush with Deuce McAllister taking the majority of rushing attempts. McAllister’s injury force Bush into a more prominent rushing role and exposed him as a tandem runner at best. He can settle back into that role this year. Plus, with Jeremy Shockey added to the offense, Bush will get even more open looks in the slot. The Saints’ offense could be amazing. Meanwhile, the Saints got to use a top-10 pick on DT Sedrick Ellis, who should solidify the run defense. Jonathan Vilma is a statistician’s dream, as he devours tackles and now anchors the MLB position. This Saints team is a real threat.

10. A youth movement will catapult Pittsburgh- The Stillers made two draft picks that play right into Football Know-it-All’s idea of offense. They drafted a top running back, Rashard Mendenhall, to tandem with Willie Parker. Justin Hartwig taking over at center should also offset the loss of Faneca at guard. Plus, they drafted big-play target receiver Limas Sweed, who may be the most promising rookie receiver. If these two rookies start quick, this could be a huge year for Ben Roethlisberger.

11. If the Jets offense does perform, an unlikely candidate will be the savior. Jets fans think that their running game hinges on Thomas Jones, but Jesse Chatman will be a good partner, one who may even take the starting job. Last year, Chatman was top 10 in both Side Yards and 2nd half Yards. If Favre can be convinced to let the running game take a larger role late in close games, Chatman should make the Jets glad they signed him.

12. The Bears will be fighting for the #1 draft pick. There is every reason to believe that this team is heading farther down their spiral. Their starting receivers are now slated as Devin Hester and Brandon Lloyd, neither of whom has ever shown any big play ability. The below-league-average running backs show no signs of improvement, and their QB situation is still a mess. On defense, the Bears were far worse than their points allowed indicated last year. Their yards allowed were over 355/game, but 33 takeaways saved them from giving up more points.

13. The Atlanta Falcons may beat them to it. If Matt Ryan will start this year, he has the fight of a lifetime on his hands. His line is positively sadistic, letting their varied quarterbacks hit the ground more than 50 times last year. That will also make it hard for Michael Turner to become a lone feature back, since he’s only succeeded before in San Diego’s running-back-friendly scheme. The D-Line is also the same, meaning very bad.

14. If a superstar is born out of that sorry scene, it will be Roddy White. White had 82 receptions last year for over 1,200 yards (top 10 in the NFL). In his three years in the league, White has averaged over 15 yards per reception, and has done while his QB’s were as varied as Michael Vick, Byron Leftwich, Joey Harrington and Chris Redman. Now at the age of 26, White appears on the verge of his prime. Rookie qb’s are known to latch onto and keep returning to a feature wideout, and that should be White for Ryan. 2008 could be the year the fantasy owners take notice of him.

15. A rising special teams unit will make Minnesota even more dangerous. When Adrian Peterson went down last year, Aundrae Allison took over as the kick returner and revealed that he is one of the finest in football. He virtually always returns the ball more than 20 yards and average 28.7 yards per return, more than 3 yards over league average per possession. In other words, Allison gets a team more extra yards per possession than most running backs.

16. Sleeper Pick- The Carolina Panthers. Their quarterback play was why their offense was so wretched. Jake Delhomme, unknown to even himself, had need ulnar surgery for three years and finally got it after his elbow popped last year. He has looked better in the preseason than he has in years. Combine that with a newly revamped running game that was already above average and the reunion of Steve Smith and Muhsin Muhammed, and you have a revitalized offense. The O-Line has been upgraded as well, as I note in Prediction 2. A high-tackling linebacker, Landon Johnson has been added, as well as depth on my favorite unit, the D-Line. The Panthers and the Saints will both be back this year, and one of them may end up winning the NFC.

Projecting Linebacker Units for 2008 Season

The amount of tackles per starting linebacker that a defense has is a significant predictor of a team's defensive ranking. Tackles Per Starting Linebacker (TPSL) is therefore a stat worth looking at. One should note, however, that DLI (Defensive Line Index, as discussed in previous posts) is a stronger predictor of defensive performance. In other words, better to have a great line than a great linebacking corps, generally speaking. The correlation between TPSL and Yards Allowed Per Game is 0.34, whereas DLI's correlation with Yards Allowed Per Game is 0.52.

Good news for prognosticators is that a linebacker's tackles correlate very well with each other from year to year. Therefore, the adjustments made to project last year's tackles onto this year's tackles are simply age and previous injuries. Furthermore, I looked at past first-round picks and saw how their tackle rate converted to NFl numbers in their first year. There are certainly other factors, but these three adjustments should provide a good estimate. The big changes, therefore, will come from teams who made major acquisitions, draft picks, or from teams whose linebackers are entering their prime years.

Some teams have made major upgrades and should improve their defense considerably as a result. Other teams have lost personal and may backslide.

Thus, with those adjustments made, my projection for Tackles Per Starting Linebacker for 2008 are:

Carolina Panthers- 111
San Francisco 49ers- 106
Buffalo Bills- 103
Minnesota Vikings- 100
Chicago Bears- 100
Detroit Lions- 97
New Orleans Saints- 96
New England Patriots- 96
Atlanta Falcons- 93
Houston Texans- 92
Oakland Raiders- 92
Tampa Bay Buccaneers- 91
Baltimore Ravens- 91
Seattle Seahawks- 90
Washington Redskins- 90
Indianapolis Colts- 89
San Diego Chargers- 87
Pittsburgh steelers- 87
Tennessee Titans- 86
Philadelphia Eagles- 85
New York Jets- 84
Denver Broncos- 80
Kansas City Chiefs- 76
Dallas Cowboys- 75
New York Giants- 75
Arizona Cardinals- 73
Cleveland Browns- 70
St. Louis Rams- 68
Miami Dolphins- 65
Cincinnati Bengals- 64
Jacksonville Jaguars- 62

On Thursday, I'll post my 16 Predictions for 2008.