C Scores for Current Quarterbacks

I thought it might be illustrative to show you C scores for all the quarterbacks who qualified in 2009.  With Kurt Warner retiring at the end of last season, it is certain that not all of them will qualify again in 2010, and, almost assuredly some of the remaining won't qualify in 2010.  The difficulty in looking at these players is their body of work.  Not all of them will have a C7 score, our standard measure.  That being said however, it is still worth a look.  Instead of simply limiting the list to those that have a C7 score, we will look at all of their C scores (C1, C4, C7 and C10).

Here's what the list looks like:

Not too many surprises here.

Did you expect someone other than Peyton Manning to be the best passer in the game today?  If you did, I'd love to hear from you, and I'd like to see the analysis.  Peyton Manning is one of the all-time best (see here and here), and most certainly the greatest passer of his era.  Based on C7, I currently have him 7th all-time (C7 of 644), right behind both Fran Tarkenton and Len Dawson who are tied for sixth at 646.  He has an outside chance (I'd say about 25%) of catching Sammy Baugh, who is 5th with a C7 of 654.

In the article I wrote on Kurt Warner (see here), I showed that Warner compares favorably to players like Drew Brees, and Tom Brady.  In my recent post formally introducing C scores I suggested that as far as the Hall of Fame, that Warner appears to be right on the fence.  I certainly would make the argument that Ken Anderson should be in before Warner.

In that same article I also discussed Tom Brady and Drew Brees.  I think if they both played long enough that they would both be in the HOF, and I'm fairly certain that Brees would end up as the better passer.

As far as the next group of players, certainly Carson Palmer and Philip Rivers appear to be on their way to becoming good passers, although they've still got a few years ahead of them before we can make any definitive statements.

And finally, looking further out in to the future, I'd say that Matt Schaub is an up-and-comer, and, really taking a flyer, perhaps Aaron Rodgers can parlay his early success to be considered a great passer.  Only time will tell.

A Look Back At Kurt Warner's Career As a Passer

On the Friday before Superbowl XLIV, Kurt Warner announced that he was retiring from the NFL. 


Of course, the conversations now turn to whether he will be enshrined in Canton.  There are those who say yes, some who say maybe, and those who say no.  The fact is, we don't know.  There is no formula to get in. 


In many of the posts on the topic, the usual comparisons are made.  The easiest comparisons are to his peers - Manning, Brady, Favre, Brees, and others.  The other comparisons I've seen are to players like Dan Fouts, Jim Kelly, Troy Aikman, and Warren Moon, all four of whom are in Canton.


My post is not about whether he was a good quarterback or not, and whether he should or should not be in the Hall of Fame.  This post is about whether or not he was a good passer.  And how did he compare to his peers?  And where would he rank in terms of recent quarterbacks who have retired?  And how would he compare to all quarterbacks?  These are the questions I will explore.  All of these questions will be answered in the context of his passing ability in relation to the others.


Ok, let's start with a look back at his performance over the years.

Several things jump out at me.


His career passer rating, for one.  It's very high.  According to the Pro Football Hall of Fame, Warner's career passer rating of 93.7 ranks fifth best all-time, behind Steve Young, Philip Rivers, Tony Romo and Peyton Manning.  As I have discussed before, the NFL passer rating formula isn't a very meaningful way to compare quarterbacks over time.  I'll discuss how we adjust the passer rating, and even simplify it, and then compare that figure to his peers, in order to get a more meaningful picture.  The average passer rating of 95.1 shown above differs from that shown by the Pro Football Hall of Fame simply because mine is just a simple average of each year.


Another fact that jumps out at me is that he got a late start.  He didn't start really playing until he was 28.  In my database of 416 quarterbacks going all the way back to 1932, including players from both the AAFC in the late 1940's and the AFL in the 1960's, and only looking at quarterbacks who have qualified in 8 or more years, only 7 quarterbacks had their first qualifying season at age 28 or later.  For all quarterbacks who qualified in at least 8 seasons, both the median and mean age at which they qualified in their first season is 24.  There are a total of 77 quarterbacks who qualified in at least 8 seasons.  Keep in mind that the average number of years in which a quarterback qualifies (given that he qualifies in at least 1 year) is 4.125, and median number of years is 3.  So to be one of only 7 quarterbacks who began at age 28 or later and qualify in 8 different seasons is pretty rare company.  The other six players are Jeff Garcia and Roger Staubach at age 29, and Warren Moon, Billy Kilmer, Ken Stabler, and Brad Johnson at age 28.  Note that Staubach and Moon are both in the Hall of Fame.


Next thing I notice is that there are many gaps in his career.  He got injured, then was signed by the NY Giants as an insurance policy against Eli Manning.  Following that, he ended up getting an opportunity to play in Arizona, until the Cardinals drafted Matt Leinart.  When Leinart got hurt in the fifth game of the 2007 season, Kurt stepped in, and went on to lead the Cardinals into Superbowl XLIII, and into the playoffs this past season, where the Cardinals lost to eventual Superbowl Champs New Orleans.


It is extremely difficult to use the NFL Passer Rating system, especially the career passer rating for a given quarterback to see how they compare to other quarterbacks.  Just take a look at the list provided by the Pro Football Hall of Fame.  This is simply not a list of the best passers over time.  It merely reflects the fact that the passer rating calculation favors current passers.  I have previously shown (here) why this is not an accurate reflection of passing ability.


Perhaps one way to adjust the passer rating is to reflect the standards such that the average in each year turns out to be 66.7 (as the intended application of the passer rating).  See my post on the subject here.  In that regard, Warner's (adjusted) career passer rating is around 83.  Of the 416 quarterbacks, that would rank him 23rd.  Of the quarterbacks qualifying in 8 or more years, it would rank him 10th.


While the Adjusted Passer Rating is better than the NFL Passer Rating, in that at least one can compare quarterbacks from one era with those of another, it's still not an ideal (or simple) measure of a passer's effectiveness.  I've used CMTI in the past, and I'll use it here.  More specifically, I'll use the CMTIPR, or percentile rank of CMTI.


In my previous post, I compared Manning, Favre and Brees using CMTIPR.  We had to adjust CMTIPR for length of career, and I used their best seasons as the measure.  At the end of that post, a graphical illustration showed the effect.  I've since improved upon that concept.  Using the concept of "Best Seasons", I've come up with 4 statistical measures, C1, C4, C7 and C10, that basically shows a given quarterback's best season (C1), 4 best seasons (C4), 7 best seasons (C7) and 10 best seasons (C10).  C1 is simply the quarterback's best season in terms of percentile rank of CMTI.  C4 is similarly the sum of the percentile ranks of his 4 best seasons, and so on.


So let's take a look at Warner, and how he compares to Manning, Favre, and Brees.

Obviously, neither Brees nor Warner will have a C10 score as they've not had 10 seasons in which they qualified.  I don't think one can evaluate a career based on 1 year, so let's not use C1.  It is shown simply for illustration purposes to highlight their best year.  So that leaves us with C4 or C7.  In order to truly define greatness, one must exemplify superior performance, but also perform at that level for a number of years.  The more years performing at a high level, the greater the player.  I think that C7 strikes a good balance.  In my database, there are 50 quarterbacks who have a C10 score, 95 quarterbacks who have a C7 score, and 169 quarterbacks who have a C4 score.  So, at least based on a C7 score, Warner compares very favorably to Manning, Favre and Brees.


We will go into much more details regarding the C scores for quarterbacks in my next post.

First Year Quarterback Performance - An Evaluation Method

This past weekend, the New England Patriots traded Matt Cassel to the Kansas City Chiefs.  In fact, they traded linebacker Mike Vrabel and Cassel for a 2nd round pick (pick #34) in the upcoming April draft (see here for the details).  Depending on what your news source is, this was labeled as either a good deal for Kansas City, or a bad deal for New England.  The experts discussing this issue don't seem to support their arguments by any objective measures - they just opine.  I am not going to jump into the debate here.  I will offer this however - we will probably not know who will end up on the better end of this deal until many years from now, and even then, we may not know.  

What about the objective evidence?

Matt Cassel is not the only quarterback in 2008 that had a good year as a first-year quarterback.  There was Aaron Rodgers of the Packers, Shaun Hill of the 49'ers, and Matt Ryan of the Falcons.  There were four other quarterbacks who threw enough passes this year to make the list of first-year quarterbacks - Ryan Fitzpatrick of the Bengals, Joe Flacco of the Ravens, JaMarcus Russell of the Raiders and Tyler Thigpen of the Chiefs.  

Notice here that I didn't use the term rookie quarterback, but instead used the term first year.  The way I look at a quarterback, is that I only consider a quarterback who has thrown "enough" passes to qualify in a given year.  The # of passes has varied by year (as opposed to the fixed standard used by NFL.com).  For the 69-year period from 1940-2008, my database contains 1,451 passing seasons, 336 of which were by a quarterback qualifying for the first time.

How did the aforementioned 8 quarterbacks do?  

I use a statistical measure I have previously developed and discussed, called CMI (Completions Minus Interceptions, calculated as Completions/Attempts - 3*Interceptions/Attempts) instead of the NFL Passer Rating system (using the NFL passer rating system gets you essentially the same answers), and then use the standard deviation from the mean as the measuring stick (for the pool of qualifying passers, I calculate the the mean and standard deviations for each year, and relate a particular performance in that year to the mean using that year's standard deviation).  Using the mean and standard deviation this way not only allows me to compare these 8 quarterbacks relative to each other, but also relative to all quarterbacks this year, or any other year.

In a post not too long ago, I showed how, over the past 69 years from 1940-2008, when the standard deviation is used as the measuring stick, the accumulated data form a near-perfect theoretical standard normal distribution.  And I also showed how, this is true regardless of whether one used the NFL passer rating system or CMI as the statistical base.

I can now show you how these first year quarterbacks did compare to the rest of the QBs in 2008, using this measure.  But this picture may not tell us much, if anything.  Here's the graphical illustration:

Perhaps the only thing that may be apparent from this is that first year quarterbacks don't do nearly as well as quarterbacks with more experience.  Even drawing that conclusion from this is a little iffy.  However, it is clear (at least by this measure) that Cassel had the best year of the 8 first year QBs.  Rodgers was a close second.  JaMarcus Russell and Tyler Thigpen had disastrous first years.  In an earlier post regarding Jeff Garcia, I had suggested that Kansas City might be a good place for Garcia.  Scott Pioli, the new Chiefs' GM apparently was thinking the same thing - upgrade at quarterback, and he did - with Cassel.

Going back to the standard normal curve, let's look at just the first year performances.  Recall that, when all 1,451 seasons are aggregated in a histogram, it looks very much like a standard normal curve.

This doesn't quite look "normal", does it?  The first year performances appear skewed to the left, or, compared to all quarterback performances, appear to under-perform.  Since the total database is normally distributed, then performances in years 2 and beyond must obviously be skewed to the right.  This prompts the question: does experience improve performance, and, in particular, how and when?

One way to look at this is to take the entire database, and look at the average standard deviation from the mean for each additional year a player qualified.  Here's what that graph looks like.

Wow!  I didn't realize that it takes about 5 qualifying years to turn into an average quarterback.  And that's just for those playing that long!  Even though this graph goes out to 18 years, there is hardly any data beyond the 15th year (there are only 8 quarterbacks who have had qualifying seasons 16 different years).  According to this illustration, basically, first year quarterbacks, as a group, struggle mightily.  They then gradually improve each year until about year nine.  Quarterbacks, on average, must still endure sub-par years in years 2-4, and for those that survive, their reward is about four more years of improving performance, assuming they stay healthy for that long.

Note: This analysis - the method of breaking down a quarterback's expected career in terms of passing performance as it relates to experience and how it is expected to change over time, is the first I've seen published publicly.  But I digress.

Ok, so we've taken a look at these 8 QBs relative to all quarterbacks in 2008, and we've taken a look at first year quarterbacks in general.  So the next step is to take a look at the best first year seasons.  In my database, there are 336 first year seasons in all (in other words, in the 69-year period from 1940-2008, 336 different quarterbacks threw enough passes in a season to qualify at least once).  The table below shows the 75 best.

Cassel (#48) and Rodgers (#60) are the only 2 of the 8 in 2008 that crack the top 75 all-time.  On the other end of the scale, we get JaMarcus Russell (#264) and Tyler Thigpen (#290).

When Matt Ryan (#128) got off to a solid start, and the Falcons surprised many by getting into the playoffs, there were many debates as to whether his season was one of the best ever by a first year player.  Not according to this measure.  Often, during those discussions, Kurt Warner's first year was brought up.  In looking at the table above, well, he did have an outstanding first year in 1999.  It ranks #6 all-time in terms of first year seasons.  The best ever - Roger Staubach's 1971 season (Staubach was a rookie in 1966, and played in both 1969 and 1970.  However, he didn't attempt enough passes in either year to qualify).  

Notable quarterbacks high on this list: Joe Montana in 1980 (#4), Tom Brady in 2001 (#14) - (see my post earlier comparing Brady's season to Cassel's here), Brett Favre in 1992 (#15), Dan Marino in 1983 (#21), and Johnny Unitas in 1956 (#22).  

Notable absentees:  Steve Young in 1986 (#154), Peyton Manning in 1998 (#208), Joe Namath in 1970 (#202)*, and Troy Aikman in 1989 (#311).  The all-time worst first year performance - Terry Bradshaw in 1970 (#337)*.

* Keep in mind that 1970 was the first year of the NFL following the merger, and 15 quarterbacks showed up in the database as having that year as their first year, although Bradshaw's 1970 season was his actual rookie season.

Are we done?  Hardly.  So after I went through this list, and still trying to objectively value Matt Cassel, I was interested in answering the following question(s):  what does the first-year tell us about a quarterback's future potential?  Do quarterbacks who have good first years, have good careers?  What about quarterbacks who have sub-par first years?  In other words, is there a correlation between year 1 performance and subsequent years?  When in doubt, it's always a good idea to take a look at the data.

Whoa!  The correlation between year 1 performance, and career performance, as measured by CMI standard deviations relative to the mean, is 0.75.  What that really means is that 57% of the variation in a quarterback's career performance can be explained by his year 1 performance.  I find that incredible.  So I looked a little deeper.  It turns out that 112 of the 336 quarterbacks only have 1 qualifying year.  And, for that group, the correlation coefficient is, well, 100%!  If I only looked at those quarterbacks whose career included at least 2 different years in which they threw enough passes to qualify, then the correlation coefficient drops to 64%.  Still quite remarkable.  

The table below breaks down the 336 first year seasons in terms of CMI standard deviations to see if we can glean any additional insight into whether a good first year translates into a good career and vice versa.


Well, the evidence is pretty clear.  Taken as two groups, players that have better than average (remember, the mean and standard deviation is relative to all quarterbacks, not just first year quarterbacks) first years tend to have longer careers and more productive careers than those that have sub-par first years.  And, breaking it down even further (in other words, just looking at the group whose first year was better than average, or the group whose first year was worse than average), you can clearly see that even within those sub-groups, the better the first year, the longer the career (although this correlation isn't nearly as strong), and the more productive the career. 

I haven't spent too much time on my blog discussing individual careers, except in the posts discussing Brett Favre and Jeff Garcia.  If I do this en masse, it would be such a powerful post - I'll basically be giving you my list of greatest passers to ever play the game, that I need to put a lot more thought into it than I have to-date.  In any case, some of the obvious names will show up on that list.  However, you'll find some exceptions as well (and I'm sure many of you will take exceptions to the list).  The point I really want to make here is that, when combining the table above, and the discussion following the list of the top 75 first years, it is quite remarkable how Troy Aikman "escaped" the trend, and turned into a great quarterback (or, more accurately, a great passer) - he truly turned out to be an exception (as for Young and Manning, even though they didn't rank well on the first year list, their first years weren't "that bad" compared to other first year seasons - as a matter of fact, Young's was "above average" compared to a typical first year).  Notice how I don't mention Bradshaw and Namath - it is because, statistically, their careers were sub-par.  When I publish my list of all-time greatest (and worst) passers, we'll get into it in more detail.

So, in trying to look at Matt Cassel's first year performance objectively, we've looked at how quarterbacks perform as their careers progress, how quarterbacks perform in their first year, who had great first years, where Cassel's season ranks on that list, and, how a first year translates into (or, is predictive of) a career.  Now perhaps, we can view Matt Cassel's 2008 year in an objective manner, and, if so inclined, you can at least evaluate the trade armed with some data.

Naturally, while I was putting this post together a question popped into my mind, and that is:  is a quarterback's second year a good indicator of their career?  What about looking at their first and second years?  Check back in a week or two to find out.

A Logical Look at What Happened in the Carolina vs Arizona Game

The Carolina Panthers, played in the toughest division in the NFC, the NFC South.  The Arizona Cardinals played in the easiest, the NFC West.  The Panthers completed a 12-4 season.  The Cardinals were 9-7.  The Panthers were 8-0 at home.  The Cardinals were 3-5 on the road.  The oddsmakers in Vegas decided that this was good enough to favor the Panthers by 9.5 to 10.0 points.

Result - Arizona beats Carolina 33-13

What Happened?

Jake Delhomme threw a career-high 5 INTs.  That was unexpected.  A shocker.  But, how unexpected was it, really?

Let's take a look at some #s.

First, what are the chances of winning a playoff game, when a QB throws X interceptions?  Here are the stats:

0 INTs - 184-51, a winning percentage of 0.783

1 INT - 140-112, a winning percentage of 0.556

2 INTs - 54-117, a winning percentage of 0.314

3 INTs - 17-76, a winning percentage of 0.183

4 INTs - 1-27, a winning percentage of 0.036

5 INTs - 0-11, a winning percentage of 0.000

6 INTs - 0-3, a winning percentage of 0.000

These are based on all playoff games in the Super Bowl era.  The data is courtesy of Cold Hard Football Facts.

As I have shown before, a QBs likelihood of throwing interceptions has been decreasing over time (based on the increasing value of that component in the QB Rating).  So, if one were to look at this season's regular season stats, I'm sure this table would look even more skewed.  (I don't have 2008 game by game data handy).  The point is still the same - throw INTs, and you dramatically reduce the likelihood that your team wins.  The fact that someone threw 5 picks is actually quite irrelevant.  Once you throw 2 picks, you're likelihood of winning is dramatically reduced, and it's less than 1 in 5 if you throw 3.

Ok fine, so let's look at both QBs in this game Jake Delhomme and Kurt Warner.   According to the table below, in Jake's career (including prior post season games), he had never thrown 5 INTs in a game.  However, he had thrown at least 2 INTs in a game 22% of the time, and at least 3 INTs in a game 6% of the time.  What's perhaps most interesting is that Kurt Warner had thrown at least 2 INTs in a game 28% of the time, and 3 INTs in a game 12% of the time.  

So, what does this all mean?  We need to look at the second table (see below the first table for the analysis).

According to this table, based on the likelihoods shown in the previous table there was an 18% chance that at least one of the QBs in this game was going to throw at least 3 INTs (see the last column in the table below).  That's a about 1 in 5.  That's much higher than I would have thought.  That's actually a higher likelihood than both QBs finishing the game having thrown 0 INTs.  Now admittedly, the likelihood that it was Delhomme and not Warner that was going to throw the 3 or more INTs was 2-to-1 against (given at least 1 QB would throw at least 3 INTs).  But the fact is, there was a pretty good chance that this was going to be a game where at least 1 QB threw multiple INTs.  Heck, there was about a 1 in 14 chance that at least 1 of them was going to throw 4 or more INTs - again, much higher likelihood than I would have thought (and you too, I'm guessing).

So there you have it.  An unexpected result.  Certainly.  But not that unexpected.  What should also be clear is that if you throw a pick, you're chances of winning reduce quite significantly.  And for each subsequent one, the odds of winning decrease exponentially.  After 3 picks, it's lights out.

Debating the 2009 Pro-Bowl Selections

Earlier this week, the NFL announced the rosters for the 2009 Pro Bowl.  Representing the AFC are QBs Peyton Manning, making his ninth appearance, Jay Cutler, making his first appearance, and Brett Favre, making his tenth appearance, but first time representing the AFC.  Representing the NFC are QBs Kurt Warner, making his fourth appearance, and Drew Brees and Eli Manning, who is making his first appearance.  This will be the first time that brothers playing quarterback have been selected to the Pro Bowl.

I am really not sure what criteria the voters (the players) use to select these quarterbacks.  Some probably use statistics, such as the quarterback rating, even though no one actually understands the QB rating or how it is derived.  Some probably look at the team's performance, even though the quarterback may have little to do with the team's actual performance, or won-loss record.  And then some may simply be basing it on some other factors, such as like-ability, or popularity.  Based on the selections, it appears that voters reward players for a good team record and # of touchdowns thrown (to the average fan, these two factors seem like reasonable criteria, I'm sure).  I of course disagree, but then again, that is the reason for this post.  

The Pro Bowl is meant to be a reward for performing exceptionally well on the field, and, since it is voted on by the players, a recognition from one's teammates as well as competitors.  So how do these selections stack up?

Before I get into the details, a quick refresher on the NFL passer rating calculation.  I'll keep the math simple.  The NFL passer rating is made up of four different components (see here for the details), each with a maximum possible value of 2.375, and a minimum possible value of 0.  The four components are given equal weight in the calculation of the rating.  The four components are:

Pass Completion percentage

Yards per Completion

TDs per Attempt (Touchdown percentage)

INTs per Attempt (Interception percentage)

In the table below, I show how each of the quarterbacks scored on each component, how that translated to their QB rating, and their respective ranks (amongst each of the four components as well as the final QB rating).  I also include CMI for each quarterback, and I have previously discussed my preference for CMI versus the current NFL passer rating formula.  The players shaded in green were the ones voted in.  The players shaded in blue are my obvious snubs, and the players shaded in orange one could argue deserve to go.

Ok, now on to the #s.

AFC

Peyton Manning - As I mentioned in a previous post, he is having another great year.  He has a passer rating of 90.3 (through 14 games).  In the AFC, he ranks 5th, 7th, 4th and 6th in each of the components, good enough for 4th in terms of passer rating.  He is 3rd in the AFC in terms of # of touchdowns passes.  He has led the Colts to a 10-4 record.  He is 2nd in the AFC in terms of CMI.  Very difficult to argue against the selection.

Brett Favre - For the four components, he is ranked 1st, 9th, 2nd and 16th, good enough for 7th overall in passer rating in the AFC.  He has taken the Jets to a 9-5 record, and he has thrown 21 TDs, fourth amongst AFC quarterbacks.  He has also thrown 17 INTs, worst in the NFL.  He ranks 7th in the AFC in CMI.  Based on statistics, should not have made it.  The only explanation is that he is probably perceived to have helped turn around the Jets, and he has thrown a lot of touchdowns.

Jay Cutler - Jay Cutler got off to a red-hot start, and has since cooled off.  He ranks 9th, 4th, 3rd and 11th on each of the four components, placing him 5th in the AFC in Passer Rating.  The Broncos are 8-6, and his 24 touchdowns are second only to Philip Rivers' 28.  His CMI places him 9th in the AFC.  Based on statistics, again hard to see why he got voted into the Pro Bowl.

NFC

Kurt Warner - He led the Cardinals to a 8-6 record and the NFC West Division title.  He ranks 1st, 4th, 4th and 7th in each of the components, good enough for 2nd in the NFC in passer rating.  He has thrown 26 touchdowns, 2nd best in the NFC.  He ranks 2nd in CMI in the NFC.  Based on the #s, good enough to go.

Drew Brees - Started out blazing, but has had a couple of mediocre games recently.  Has led the Saints to a 7-7 record, and has thrown a league-high 28 touchdowns.  He has also thrown an NFC-high 16 interceptions.  He ranks 3rd, 3rd, 2nd and 10th in each of the components, good enough for 4th in the NFC in terms of passer rating.  He ranks 4th in CMI.  An acceptable choice for the Pro Bowl.

Eli Manning - He has led the NY Giants to an 11-3 record, coming off that Giant upset in last year's Super Bowl against the previously undefeated Pats.  He has thrown 20 touchdown passes, only 6th-best in the NFC.  His ranks in the four components are 10th, 11th, 5th and 5th respectively - making his passer rating only 9th-best in the NFC.  His CMI rank is 10th.  Clearly a sentimental pick here.  I would not have voted him in.

In summary,

Peyton Manning - In

Brett Favre - Out

Jay Cutler - Out

Kurt Warner - In

Drew Brees - In

Eli Manning - Out

Obvious Snubs

There are two, in my mind - one each in the AFC and NFC, respectively.  

In the AFC, Chad Pennington is an obvious snub.  Clearly, he doesn't get attention amongst his peers, because he doesn't throw a lot of touchdowns.  I've never understood why throwing a touchdown is so important to determining how good a passer someone is.  CMI, which has a 97% correlation with the current NFL passer rating, doesn't include touchdowns.  Pennington has thrown for only 14 touchdowns.  He has led the Miami Dolphins to a 9-5 record (keep in mind that Miami only won 1 game last season).  Based on the four components, he ranks 3rd, 3rd, 10th (the component associated with TDs), and 1st, good enough for second-best in the AFC in passer rating.  He ranks 1st in CMI.

In the NFC, Jeff Garcia is an obvious snub.  Although he has led the Bucs to a 9-5 record, he suffers from the same 'disease' that Pennington has.  He doesn't get a lot of recognition around the league for how good he is because he doesn't throw a lot of touchdowns.  He has 'only' thrown 10 touchdowns.  That hurts him in terms of passer rating, as he ranks, 2nd, 7th, 12th and 1st in each of the components, good for 3rd in the NFC in terms of passer rating.  He ranks #1 in the NFC in CMI.

Possibly Overlooked

In the AFC, both Matt Schaub and Philip Rivers have possibly been overlooked.  Matt Schaub has led the Texans to a 7-7 record, and has a passer rating of 92.7, 3rd-best in the AFC.  In terms of the four components, he ranks 2nd, 2nd, 6th and 13th, respectively.  He is 3rd in the AFC in CMI.  Philip Rivers, although having a good year (in terms of the traditional touchdowns thrown), suffers from the Chargers being 6-8.  He leads the NFL in passer rating at 101.4, and leads the NFL in touchdowns thrown with 28.  He ranks 6th, 1st, 1st and 7th in each of the components, and ranks 4th in the AFC in CMI.

In the NFC, Jason Campbell and Aaron Rodgers have both been overlooked in my opinion.  Campbell's Redskins are 7-7 on the season, and he has thrown 'only' 12 touchdowns.  He ranks 7th, 12th, 13th, and 2nd in each of the four components, good enough for only 10th in terms of passer rating.  He ranks 3rd in CMI.  What hurts Rodgers most is the fact that the Packers are 5-9.  He ranks 4th in the NFC in touchdowns thrown, with 23.  He ranks 4th, 6th, 3rd and 9th in the four components, good for 6th in the NFC in passer rating.  His CMI rank is also 6th.

In looking at all these quarterbacks, something struck me, and that is the exceptional seasons that Garcia, Campbell and Pennington are having in terms of the infrequency of interceptions thrown (see here for their stats).  I'll have a post on this later.

It appears to me that what gets attention (and votes) is winning and throwing touchdowns.  At some point I will do an extensive analysis showing the relationship between a quarterback and winning.  What doesn't get attention (but should) is interceptions thrown.  

The table below shows the stats for the NFL's quarterbacks through 14 games this season (only those who 'qualified' (i.e. those throwing at least 224 passes) are shown.

Is Matt Cassel The New Tom Brady?

Matt Cassel of the New England Patriots is having a good year.  He is 13th in the NFL in Passer Rating, after 14 games.  And, in what may seem eerily similar to one Mr. Tom Brady, he replaced Brady in the first game of the season, when Brady was lost to the season as a result of a leg injury.  Flashback to  September 2001, and the aforementioned Brady, replaced Drew Bledsoe as the quarterback of the New England Patriots.  The rest, as they say, is history.

That year, Tom Brady had a great year.  A dream year.  Replacing Bledsoe in the 2nd game of the season, he went on to lead the Patriots to an 11-5 regular season record, and on to win Super Bowl XXXVI, 20-17 over the St. Louis Rams.  Brady was selected to the Pro Bowl, and was named Super Bowl MVP.  He finished 6th in the NFL in passing, with a Passer Rating of 86.5, and he had a CMI of 0.552 (see the table below).  That year, the league average CMI was 0.497, and his CMI was 1.25 Standard Deviations above the average.  Only Rich Gannon (2.54), Kurt Warner (1.57), and Jeff Garcia (1.33) had a better year that year.  

The graph below the table shows that he started out a little slow (understandably so), and played fairly consistently throughout the year, with a few spectacular (and one not so spectacular) games thrown in.  He didn't throw an interception in his first five games, but then threw 4 in a 31-20 loss at Denver in game 6.  All in all, he didn't throw a pick in nine games, the Patriots going 7-2 in those games.

So, how is Matt Cassel doing trying to imitate Tom Brady?

As mentioned earlier, his current Passer Rating is 87.1, a shade higher than Tom Brady's 86.5.  His CMI is 0.568, also better than Brady's 0.552.  He has six games to-date where he has not thrown an interception, leading the Pats to a 5-1 record in those games.  So how does Cassel's CMI of 0.568 compare to Brady's 0.552?  This is where the comparison ends.  In 2008, the league average CMI is 0.542, so Cassel's performance is 0.49 Standard Deviations above the average.  Good, but not great.  Good for 9th out of 30 quarterbacks who have thrown enough passes to qualify.  The table below shows a game-by-game comparison of Cassel's performances compared to Brady's 2001 season.