True Quarterback Value - Debunking ESPN's Total QBR
By Jeff Pasquino
August 31st, 2011

So who is better, Drew Brees or Peyton Manning? Debates like these are commonplace in sports bars all across the country, and they are one of the main reasons why quarterback rating formulas were invented. The statisticians thought "what better way to compare quarterbacks than a number that represents how good those quarterbacks play?", which is why the NFL Passer Rating statistic was invented way back in 1973. Well, most NFL fans know already that the formula to calculate NFL Passer Rating has several flaws, which is why many have tried to put out different methods of valuing the quarterback position.

First let us talk briefly about the issues with NFL Passer Rating statistic. I will not go into all the calculations, but I will touch on the numbers that go into the formula. All that matters for this formula are completions, passing yards, touchdown passes and interceptions. That's all - and it sounds pretty simple. But if you look at the formula, you immediately start to see the flaws. Every statistic is scaled on a "per pass attempt" basis, meaning that a quarterback spiking the ball to kill the clock or throwing it away to avoid a sack actually hurts his rating - which sounds wrong if you really want to see how effective a quarterback is at helping his team win. The other flaw is that there are caps to each statistic as to how much it can count - meaning that some amazing performances are no better than very good ones. The easiest example is that a perfect rate of touchdown passes is one every 8.4 pass attempts. If a quarterback throws a touchdown every eight, seven or even five pass attempts, it is all the same within the formula. So a quarterback throwing five touchdowns on five pass attempts is the same as one who throws five touchdowns on 40 attempts. That does not sound fair at all, and it isn't - but that is how the formula works, and it is one of the reasons why people are constantly trying to build a better QB rating system.

Now comes 2011, the year when ESPN has decried that this is the "Year of the Quarterback". Of course it makes the most sense to put out their own version of a quarterback ranking system, this one called The Total QBR, or Total Quarterback Rating system. They were so proud of it that they pushed it for weeks leading up to a prime time special that went over the rating - sort of. They claimed that they went back and looked at all the plays of every NFL game for the past three years (and in special cases like Tom Brady, another season) and "ran the numbers" to come up with this Total QBR statistic for each quarterback.

That sounds great, but here is what REALLY happened. ESPN spent six months and several thousand man-hours on a task that has virtually no real value to anyone outside of ESPN. What about their formula? So far it has not been released to the public, and I am not sure it ever will be. They said during their special that it looks at how a quarterback performs in a given situation and rates that performance against others in similar situations based on play-by-play analysis for the past 10 seasons. They take into account the number of rushers the QB saw on a given play, was he under duress or on the run, and how accurate the ball was thrown. Accuracy, length of throw, whether it was tipped or batted down, and the amount of yards per pass completion attributed to both the throw and the yards the receiver gained after the catch were all factored into each play.

So what is the downside? Well, based upon the inherent fact that you have to watch every single play and then grade each play - two major flaws in this system come up right away. First, historical perspective is immediately lost. There is no way to go back throughout history and say whether or not a given quarterback had a great Total QBR game or season or not since you cannot watch each game either because there is no video or that the quality of the video is subpar. The second flaw is the subjectivity of the rating system. Any system that requires a review to judge the quality of a performance is automatically subjective by nature, which is just asking for trouble in trying to create an objective rating system.

Other flaws appeared throughout ESPN's special. I knew going in that ESPN is going to carry this Total QBR thing forward, so I was curious how they would incorporate it during this season. As it turns out, they claimed it to be "real time", yet the truth is that a QBR for each NFL game will not be available for at least 12 hours after the completion of each contest. So much for real time, right? Why exactly? Go back and read the part about the subjective judging a few paragraphs ago. Someone has to go back and watch every play and rate the performance in order for ESPN to compute this statistic. That sounds way too complicated to me.

So what about other quarterback rating formulas? There are many of them out there, and I will include a few as references at the bottom of this article, but they all tend to share similar tradeoffs and traits. Most of these alternative systems, for example, try and compensate with either a translation attempt to one statistic (such as converting touchdowns or interceptions to a yardage value) and then using yards per attempt or a more complex version of that (such as adjusted yards per attempt) to come up with their quarterback rating. To me, that seems a bit mechanical and not really straightforward. Why is a touchdown worth 20 yards? Why is an interception worth -45 yards, but a fumble is worth -35? I understand that there is a method to that madness - but even though I have lots of math in my background I tend to gravitate towards simple solutions. I am not a really big fan of trying to reverse engineer the math and make the numbers fit the results, nor am I one to try and say "a touchdown is worth X yards". That seems wrong to me, and I thought there had to be a better way.

Introducing QBV - The Quarterback Value Statistic

So my goal was to develop a way to rate quarterbacks that makes sense when you read the formula from a football perspective, and have the formula fully disclosed that anyone can use it going forward or backwards throughout football history. Most of all, I wanted the system to be as simple as possible using statistics readily available in football box scores or that can be easily calculated while watching a game. What follows here are the first results of an attempt to do all of the above.

The first part of the goal is to define what stats make sense to use to really evaluate the performance of a quarterback. Asking the simple question of "What does a good quarterback do when he is succeeding?" brought me to three simple goals for QB success:

  1. Scoring points
  2. Moving the ball down the field
  3. Not giving the ball to the other team

Using those three goals above, I have a few simple ways to measure each of those goals that make logical sense and are easy to understand. Let us start with Goal #1 - Scoring Points. Quarterbacks are in charge of the offense, and there is no better way to gauge productivity than by using the scoreboard. The first way is by giving seven points for every touchdown pass, because that is how many points should be up on the scoreboard after the touchdown and what should be an automatic extra point. Seven points are also awarded for a rushing touchdown by the quarterback for the same reason. An additional point is given for any two-point play in which the quarterback is involved (either the QB running it in or throwing for the conversion).

The next one takes slightly more thought, but a quarterback also gets three points for any field goal attempt. The reason is that the quarterback has put his team in a position to put points on the board, so if the head coach believes that the field goal kicker should be able to convert the kick, the quarterback has done his job if he moved the offense into scoring range. Of course the argument can be made that he should have got his team the touchdown, or if there is a circumstance where he actually lost yardage that cost his team yards or he barely got to a point for a very, very long kick at the end of a game or a half - but I realize that no scoring system is perfect. The majority of the time when a quarterback gets his team inside of the other team's 35 yard line or closer and does not turn the ball over then he has done his job - so give him three points. He may have lost ground, but at least he is able to leave the field with his kicker having an opportunity to put three more points on the scoreboard. Lastly, he is not the guy kicking the ball, so if the head coach thinks that the field goal is worth the attempt, then the kicker should make the kick, and the quarterback has nothing to do with it. So every attempt is worth three, not just a made field goal, as the QB did his job to set up that attempt.

The last award for points scored is a slightly bigger leap of faith, but it does make sense when you use the above scoring methods. Every quarterback gets five points for a rushing touchdown by his team - even if he did not personally run the ball into the end zone. Why? Well, he got his team into scoring range and he helped his offense earn seven points (not three or zero), so he should be given some credit for it. The basis of five points is a simple "split the difference" of three points for a field goal and seven for his own touchdown. Of course there are counter-examples (such as giving the ball to your running back who dashes 80 yards for a score), but that exists with nearly every system. By awarding five points here, a quarterback gets some credit for when he drives his team to a goal line situation but does not put the ball into the end zone himself.

So to summarize Goal 1, every quarterback gets the following:

  • 7 Points for a Passing TD
  • 7 Points for a Rushing TD (his own score)
  • 5 Points for a Rushing TD (not his own score)
  • 3 Points for a field goal attempt
  • 1 Point for a 2-point pass
  • 1 Point for a 2-point rush
  • Now we turn towards moving the ball down the field, Goal #2. This one is pretty simple and it is based upon the reasonable thought that an offense moving the ball down the field on the other team is a valuable thing, as it keeps the other team's offense on the sideline, chews up the clock and also sets up the team for points. With that simple idea in mind, a quarterback gets one point each for every passing first down by the team. He also gets one point for any rushing first down that he himself rushes for, so a scrambling quarterback now is rewarded using this system.

    So to summarize Goal 2, every quarterback gets the following:

  • 1 Point for every passing first down
  • 1 Point for every rushing first down (by the QB himself)
  • The last goal, Goal #3, is to keep the ball away from the opponent. That means no turnovers and no punts, so all of those plays result in negative points for the quarterback. Give him -1 for every team punt (the opposite of a first down) and -4 points for every turnover in which he is directly involved (interception or one of his fumbles). Why -4? Well, if a punt is -1 and a touchdown (for the other team) can be viewed as -7 in value, -4 is right in the middle. A turnover should count for much worse than a punt as it could directly result in a score (so -7 right away) or it could take away a scoring opportunity for his own team. A case could be made for a different value, but -4 seems like a good number.

    One other event also costs the quarterback some value, and that is a turnover on downs (failed fourth down attempt). This is worse than a punt (-1) but sometimes not quite as bad as a turnover, so I give this a value of -3 points. This applies to any team turnover on downs, even if a running back fails on a fourth and one run up the middle. Why? Here is another example where a quarterback could audible out of that play and possibly get the first down with another option, so he is not completely absolved of that failure. The negative three points also works well when you think that a fourth down attempt is often at or near field goal range, so this could be viewed as taking a potential of three points off of the scoreboard.

    So to summarize Goal 3, every quarterback loses points for the following:

  • -1 for a team punt
  • -3 for a failed fourth down conversion
  • -4 for an interception
  • -4 for a fumble (by the quarterback) recovered by the other team
  • There is one final adjustment to this formula, and that is a scaling factor. Uh oh - looks like you're starting to rig the system here…. Actually far from it. I went back and forth on whether to do this or not and finally decided that it was OK to use a multiplier just because everyone seems to love the number 100 for a great quarterback score. I considered going back in the past and calculating what the scaling multiplier should be (using really good historical numbers and highly rated performances) but then I decided that it really was not necessary. So here it is - multiply by two. Yes, that's the complexity I added. Tricky, huh? Hard to do, right? Not really - and that's the point.

    So to put the whole formula out there for your consideration, I declare the QB Value (QBV) to be:

    Goal 1 = 7 * Passing TDs + 2 * QB Rushing TDs + 5 * Team Rushing TDs + 3 * FG Attempts + QB rushing 2-pointers + QB passing 2-pointers

    (Note that QB Rushing TDs are counted twice, so it nets out as 7 with QB Rushing TDs worth 2 and Team Rushing TDs worth 5)

    Goal 2 = Passing First Downs + QB Rushing First Downs

    Goal 3 = -1 * Punts + -3 * Failed 4th down tries + -4 * INTs + -4 * QB Fumbles lost

    QBV = 2 * (Goal 1 + Goal 2 + Goal 3)

    That's it in a nutshell. Score points. Move the offense. Hold on to the ball.

    So before we look at some results, why is this any better than the others that are out there? For one, it is pretty easy to explain when you see what things are being added up within the three major categories. Everyone can understand that a quarterback's job is scoring points, moving the offense and keeping the ball out of the hands of the opponent. That is the obvious benefits from this approach - but are there more? Yes, yes there are. For one, there is no upper or lower bound to the scoring system. In the current NFL QB rating system (the QB Passer Rating system), a quarterback can max out the score at 158.3. Even if he throws five touchdowns on his next five passes, he will never score better than that number. ESPN's Total QBR is also capped at 100 (it would seem) so the QB Value has more dynamic range to it. Another benefit is that the QB Value can go negative - something neither ESPN nor the NFL QB passer rating system can currently do as they have a baseline of 0.0 points. Granted you can pretty much tell that a QB is terrible if he puts up a Blutarsky, but sometimes you want to separate the terrible from the awful. Sometimes you wonder if your team would have been better off without that quarterback for the day, and a negative score would tell you just that. That is now possible, thanks to QB Value.

    Other benefits to the QB Value system include the incorporation of zero valuations for spiking the ball and throwing it out of bounds when no one is open. In the NFL QB passer rating system (and several others), quarterbacks would be penalized for the extra pass attempt - lowering all of their ratios of touchdown passes, completions and yards per attempt. That does not seem fair, so QB Value gets the nod here.

    Another positive for QB Value is the inclusion of rushing first downs and rushing scores by the quarterback. Rushing quarterbacks are not fairly represented for their true value, and this system more accurately reflects their true worth. A side benefit is that rushing yards do not come into play, so taking a knee at the end of a game or half is not a negative event. Scrambling quarterbacks that score touchdowns and pick up first downs are justly rewarded with QB Value.

    ESPN's Total QBR is also fatally flawed in that you have to watch every snap and subjectively judge each play for the quarterback's performance. That sounds good, but how realistic is that to do either going forward or back throughout NFL history? Even a flawed system like the current QB Rating can go back in time, so you are seriously going to put out a number without any historical context? That seems ridiculous to me - and way beyond the introduction of other stats (such as starting to keep track of sacks by individual players since 1982). Glossing over that fundamental flaw is careless at best.

    I know that there are drawbacks to the QB Value formula, since it is completely additive and a quarterback who does not play a full sixty minutes may be underrepresented using this statistic. I do want to point out, however, that if a quarterback either starts the game on the bench or if he gets injured during a game, that should negatively impact his overall value. A case can be made that a QB in a blowout being pulled late in a contest could be an issue, but again if he is racking up the points then this should be a modest impact at best.

    Another concern that has been raised about this is that there is no inclusion of yardage of any kind. I understand that this is a different way of looking at performance, but ultimately it does not matter how many yards an offense produces. Take for example the extreme situation where a defense consistently forces turnovers in the opponent's red zone. Is the quarterback to be punished in his rating system because he starts with a short field? I argue that the answer is no - but he better put points on the scoreboard.

    Now no system is flawless, but I would put this up against other systems - and I am about to do just that in a table for your review in a moment. I have computed the QB Values for the Top 31 rated passers for 2010 and compared it to the Top 31 ranked NFL QBs in the traditional QB Rating System and included two QBs that ESPN's QBR added who played less than enough to qualify for full ranking - Tony Romo and Colt McCoy. Table 1 highlights both the ratings and the rankings in all three systems:

    Quarterback
    QBV
    QBV Rank
    QBR
    QBR Rank
    NFL Passer Rating
    NFL Pass Rank
    Tom Brady 
    65.5
    1
    76.0
    1
    111.0
    1
    Michael Vick 
    65.5
    1
    66.6
    5
    100.2
    4
    Drew Brees 
    61.6
    3
    65.9
    6
    90.9
    13
    Philip Rivers 
    61.5
    4
    63.2
    9
    101.8
    2
    Peyton Manning 
    60.6
    5
    69.5
    2
    91.9
    11
    Ben Roethlisberger 
    54.7
    6
    59.8
    10
    97.0
    5
    Matt Schaub 
    54.4
    7
    57.8
    13
    92.0
    10
    Matt Ryan 
    54.3
    8
    68.6
    3
    91.0
    12
    Aaron Rodgers 
    54.1
    9
    67.9
    4
    101.2
    3
    Jon Kitna 
    48.0
    10
    46.1
    22
    88.9
    15
    Josh Freeman 
    47.0
    11
    63.5
    8
    95.9
    6
    Matt Cassel 
    46.3
    12
    51.2
    16
    93.0
    9
    David Garrard 
    45.7
    13
    57.3
    14
    90.8
    14
    Shaun Hill 
    44.2
    14
    44.8
    23
    81.3
    24
    Eli Manning 
    43.8
    15
    64.3
    7
    85.3
    18
    Joe Flacco 
    43.5
    16
    58.1
    11
    93.6
    8
    Carson Palmer 
    43.1
    17
    46.7
    19
    82.4
    20
    Colt McCoy 
    43.0
    18
    46.6
    20
    74.5
    29
    Kyle Orton 
    42.3
    19
    46.6
    20
    87.5
    16
    Jason Campbell 
    41.7
    20
    43.8
    24
    84.5
    19
    Mark Sanchez 
    39.9
    21
    47.4
    18
    75.3
    28
    Tony Romo 
    37.4
    22
    58.1
    11
    94.9
    7
    Ryan Fitzpatrick 
    37.4
    22
    48.7
    17
    81.8
    23
    Jay Cutler 
    37.2
    24
    42.6
    25
    86.3
    17
    Donovan McNabb 
    37.1
    25
    41.0
    28
    77.1
    25
    Chad Henne 
    36.7
    26
    41.4
    27
    75.4
    27
    Sam Bradford 
    36.5
    27
    41.0
    28
    76.5
    26
    Matt Hasselbeck 
    28.0
    28
    42.4
    26
    73.2
    30
    Alex Smith 
    26.9
    29
    40.0
    30
    82.1
    22
    Kerry Collins 
    20.0
    30
    56.0
    15
    82.2
    21
    Brett Favre 
    18.3
    31
    25.8
    32
    69.9
    31
    Derek Anderson 
    13.7
    32
    35.9
    31
    65.9
    32
    Jimmy Clausen 
    6.5
    33
    11.7
    33
    58.4
    33

    Table 1: Top Quarterback Ratings for 2010 in QB Value, QBR and NFL Passing Rating

    Note that Tony Romo and Colt McCoy are highlighted as not having enough pass attempts to qualify for NFL Passer Rating rankings.

    It is nice to see that everyone got Tom Brady right as the #1 quarterback in 2010, but only QB Value has Vick right there with Brady. In fact, if you did not count Vick's appearance after Kevin Kolb got hurt, his value would even be above Brady's QB Value score. Now let's look at the big disconnects between all three lists. Who stands out with their rankings? ESPN's Total QBR and QB Value (QBV) both love Ben Roethlisberger more, and I would tend to agree that he is indeed a Top 10 quarterback for 2010. Both Matt Ryan and Peyton Manning are higher than in NFL QB Passer Rating, a good reflection of their true values to their respective teams. Aaron Rodgers is lowest on QB Value due to his concussion issues and missed time, something the other two lists gloss over. The same can also be said for Tony Romo's injury, while not his fault but it did happen and cost the Cowboys in a big way last year.

    One more thing leaps out at me, which is ESPN's Total QBR score for Eli Manning. Somehow they have the quarterback who threw for 25 interceptions rated not only in the Top 10, but as the 7th best quarterback in 2010, ahead of Philip Rivers and Ben Roethlisberger. How is this even possible? I have heard Trent Dilfer (a very good analyst, but now way too married to both ESPN and the Total QBR - more on that in a minute) say that Eli Manning should have only had 12 or 13 interceptions last year because the other 12-13 passes were either tipped balls or bad routes run by his wide receivers. That is all well and good, but (1) 12-13 interceptions is still not elite, and (2) pretty much every quarterback has issues with tipped balls or bad routes run by his targets over the course of their career. Why make excuses for it? The numbers are what they are - making up a subjective rating to try and pull that out really looks like a big mistake to me. If you do not believe me, realistically answer the question as to whether you would want Eli Manning instead of Philip Rivers or Ben Roethlisberger to win you one game. That should tell you all you need to know about ESPN's Total QBR rankings for 2010.

    There was some value in watching ESPN's diatribe on their new favorite statistic. During that broadcast, ESPN highlighted six individual performances and stated the starting quarterback's Total QBR for that contest. First up was the Top 5 Total QBR games over the past three years. Table 2 summarizes each of those games, and also includes their statistics, NFL Passer Rating and their QB Value (QBV):

    Quarterback
    Date
    Opp
    Passing Stats
    Comp-Att-Yds-TD-INT
    Rushing Stats
    Att-Yds-TD
    ESPN
    Total QBR
    NFL QB
    Passer Rating
    Pasquino
    QB Value
    Tom Brady
    12/27/2009
    JAX
    23-26-267-4-0
    2-4, 0 TD
    98.7
    149.0
    96
    Aaron Rodgers
    1/3/2009
    AZ
    21-26-235-1-0
    2-2, 1 TD
    98.7
    117.1
    72
    Jay Cutler
    9/8/2008
    OAK
    16-24-299-2-0
    5-9, 0 TD
    98.8
    137.5
    88
    Drew Brees
    12/18/2009
    NYG
    23-30-369-4-0
    1-6, 0 TD
    98.9
    156.8
    116
    Michael Vick
    11/15/2010
    WASH
    20-28-333-4-0
    8-80, 2 TD
    99.8
    150.7
    132

    Table 2: Top 5 ESPN Total QBR Games Since 2008

    First, the good news. Four of the five games look quite reasonable for big game performances, with quarterbacks throwing for 290+ yards or two or more scores in all but one result - the Aaron Rodgers vs. Arizona game. Before we dissect that one, we will give credit where it is due and say that the other four games are correct with a high ranking of 98+ points. Each quarterback had a Passer Rating over 137 and a QB Value of 88 or more - fantastic numbers.

    Now for the downsides. There is very little way to discern the difference between any of these four games - they are all so close in QBR (98.7 to 99.8) that it is really hard to tell how "excellent" the quarterback performed. How much better is 99.8 than 98.7? According to Passer Rating, Michael Vick was close to perfect with a 150.7, but so was Tom Brady (149) and Jay Cutler was not far behind (137.5). In fact, Drew Brees had nearly a perfect rating (156.8, perfect is 158.3) but still had a lower Total QBR score than Vick.

    Once you bring QBV into the picture, it becomes much clearer. While all four performances (again, excluding Aaron Rodgers) range from 88 to 132 - all excellent scores, but now you have some way of telling great from excellent to superb. Anyone who watched Michael Vick shred the Washington Redskins on Monday Night Football last year knows that his performance was one for the ages, and when you include his rushing numbers (8-80, 2 TDs) into the mix the full story comes into picture. Vick's QBV was 132, well above any other QB on the list.

    Finally, we can now touch on Aaron Rodgers' game against Arizona. Now, I do NOT mean the very memorable playoff loss to the Cardinals (a see-saw adventure that went to overtime knotted at 45-45). ESPN chose the Week 17 game a week prior to that epic contest for some inexplicable reason. Now Rodgers did throw one touchdown and zero interceptions, and he did dive in for a touchdown from the one-yard line, but I do not see "super" numbers or performance here at all. For a quarterback's game to be one of the Top 5 games in the past three years, I would expect much more than 235 yards passing and one touchdown throw. Even the NFL Passer Rating (117.1) and my QBV (72) have this as just a "good, not great" game. Yet another strike against Total QBR.

    I stated earlier that I would get back to Trent Dilfer, and he also brought up what he thought was a great example of how Total QBR painted a much more complete picture of quarterbacking. Philip Rivers helped San Diego to beat Dallas back in December of 2009, and video study of the game afforded Rivers a QBR of 96.3. Table 3 summarizes the performance:

    Quarterback
    Date
    Opp
    Passing Stats
    Comp-Att-Yds-TD-INT
    Rushing Stats
    Att-Yds-TD
    ESPN
    Total QBR
    NFL QB
    Passer Rating
    Pasquino
    QB Value
    Philip Rivers
    12/13/2009
    DAL
    21-32-272-1-1
    3-1, 0 TD
    96.3
    96.3
    42

    Table 3: Philip Rivers vs. Dallas - December 2009

    Dilfer explained that Rivers played beyond the numbers, and that his interception was meaningless since Dallas did not score on the ensuing possession. That is careless analysis at best, since Rivers was throwing from his own end zone and was intercepted at his own 25-yard line with 1:53 left in the first half. Just because Dallas was inept at getting points in that situation does not excuse Rivers from turning the ball over to put the other team immediately in scoring position. No reasonable analysis can place this quarterback performance amongst the Top 5% of games in the past three years, yet that is exactly what the 96.3 QBR score wants you to believe.

    So what about games that were omitted? The inclusion of Aaron Rodgers' Week 17 game made me wonder about the Green Bay - Arizona Wild Card game the following week. I have no idea why ESPN did not include this, but you be the judge of how great these quarterbacks were that day:

    Quarterback
    Date
    Opp
    Passing Stats
    Comp-Att-Yds-TD-INT
    Rushing Stats
    Att-Yds-TD
    ESPN
    Total QBR
    NFL QB
    Passer Rating
    Pasquino
    QB Value
    Aaron Rodgers
    1/10/2009
    AZ
    28-42-423-4-1
    3-13, 1 TD, 1 Fum
    ???
    121.4
    110
    Kurt Warner
    1/10/2009
    GB
    29-33-379-5-0
    0-0, 0 TD
    ???
    154.1
    132

    Table 4: Two Big QB Performances - Arizona vs. Green Bay - January 2009

    Maybe - MAYBE - you can say that Aaron Rodgers was not a Top 2-3% quarterback that day, but clearly Kurt Warner must have been with five touchdown passes, only four incompletions and a near-perfect 154.1 Passer Rating. His QBV for that day was 132 - right on par with Michael Vick against the Redskins on Monday Night in 2010, the highest game ranked by ESPN for the past three years. Time for you to be the judge here.

    The Final Drive

    Let's get back to QB Value itself and where it fits in against both QBR and the NFL Passer Rating system. So how can we compare all of these numbers? Statistics gives us a way, known as correlation. The more correlated a series of numbers are, the better that they are related to each other. Table 5 shows the correlations between all three sets of numbers, for the Top 10, Top 20 and all 33 quarterbacks listed:

    Correlations
    QBV to QBR
    QBV to NFL Pass
    QBR to NFL Pass
    Top 10
    53.00%
    47.60%
    43.40%
    Top 20
    74.00%
    71.60%
    69.80%
    Top 33
    84.50%
    82.60%
    83.30%

    Table 5: Correlations Between QB Value (QBV), QB Rating (QBR) and NFL Passing Rating

    It is interesting to note that only modest correlation happens in the Top 10, but after 20 numbers it starts to show a slight trend. QB Value matches up well to both ESPN's Total QBR and the NFL Passer Rating for both the Top 20 and all 33 names on the list. In fact, QBV does better in all three metrics than ESPN's much more complicated - and secretive - QBR values.

    Much more work does need to be done, such as looking at how many scores appear above 100 and below zero and how these numbers stack up over history, but I have to say that I like the first take on this new system - and it doesn't take a whole network of NFL analysts to construct and hype for their own benefit.

    As always, questions, suggestions and comments are always welcome to pasquino@footballguys.com.

    References

  • Chase Stuart's QB Rating System
  • Luis DeLoureiro - Building a Better Passer Rating
  • Luis DeLoureiro - Pursuit of a Total Quarterback Rating
  • ESPN's Total Quarterback Rating (QBR)
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