Did Brett Favre Produce All Those Wins?

Posted on September 23, 2007 by

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History was made when the Green Bay Packers defeated the New York Giants last Sunday.  With this victory — the 149th of Brett Favre’s career — Favre set the all-time record for wins by a starting NFL quarterback.

Players are generally taught that there is “no I in team” and we “win or lose together.”  Still, in baseball every win and loss is credited to a specific pitcher.  And it is a milestone when a pitcher “wins” 300 games in his career or “loses” 20 games in a single season. 

In football this is a less common practice.  Favre setting the all-time record for wins was not widely noted.  One would also have to do a fair amount of research to learn what the won-loss record was for each quarterback in the NFL.  In fact, one could argue – which I am about to do — that assigning wins and losses to a quarterback is not entirely warranted.

Brett Favre’s Wins Produced

Quarterbacks do quite a bit in the course of a football game. Quarterbacks gain ground via the pass and run. But they also lose ground from sacks.  And as Favre closes in on the all-time interception record, we see that signal callers also turn the ball over via interceptions and fumbles. 

Given all that quarterbacks do, perhaps it’s not surprising that we believe these players are the difference between winning and losing.  But when we look at the numbers, a different story is told.

In The Wages of Wins we noted the value of yards, plays (passing attempts + rushing attempts + sacks), and turnovers in terms of net points and wins.  Table One below repeats what is said in Table 9.3 of the book (found on page 181 of the paperback edition). 

Table One: Table 9.3 of The Wages of Wins

From this table you can see that each yard gained is worth 0.08 net points and 0.002 wins.  An interception thrown, though, costs a team 2.7 points and 0.078 wins. 

With value in hands, let’s turn to the career of Brett Favre.  Favre entered the league in 1991.  If we look at Yahoo.com we can find – with but one exception — all the statistics one needs to calculate Favre’s QB Score (explained HERE), Net Points, and Wins Produced. The one exception is fumble lost.  According to Yahoo.com, Favre did not fumble until 1994.  Actually if you look at all players in history at Yahoo.com you will see that no player fumbled before 1994.  Since I am pretty sure I remember fumbles happening before 1994, this means that either no one bothered to either keep track of this stat or make this information available to Yahoo.com.  Either way, we have a hole to fill in Favre’s record.

From 1994 to 2006, Favre averaged 0.64 fumbles lost per 100 plays.  Given this record, we can assume that Favre lost 7.4 fumbles his first three seasons (by the way, if we didn’t make this effort the story being told here would be the same).  And with this data in hand, we can now calculate how many net points and wins Favre has produced in his career.

After 243 career games (through last week), Favre has gained 56,929 yards.  These yards were gained on 9,262 plays, of which 334.4 (remember, we are estimating a few fumbles) resulted in turnovers.

Put this all together, and we see that Favre has produced 1,620.1 net points in his career. And these points are worth 41.5 Wins Produced.  Again, his team has won 149 games in his career.  So the analysis of wins suggests that Favre is responsible for 27.9% of his team’s wins.

On the one hand, one NFL player is worth nearly 30% of a team’s wins.  So this suggests Favre is pretty important.  Of course, on the other hand (and economists always have another hand), Favre – the player we are crediting with each win – is not responsible for 72% of his team’s wins.

 Crediting Statistics

And the 28% we are crediting to Favre assumes that he should receive full credit for all his statistics.  And that is one assumption I am not comfortable making.

To understand my hesitation, consider baseball for a moment.  Hitters bat entirely by themselves, and hence we can feel comfortable assigning responsibility for whatever happens during each at-bat to the hitter. When we look at pitchers – the players we are assigning wins and losses – it’s a different story.  Pitchers – as JC Bradbury notes in a forthcoming article in The Journal of Sports Economics (which I need to devote an entire post to in the future) – are not very consistent.  Such inconsistency suggests that the stats we assign to pitchers (ERA, for example) are not just about the pitcher.

Like pitchers, except even more so, quarterbacks in the NFL are very inconsistent.  And this is because a quarterback does virtually nothing by himself. Eleven players take the field on offense.  Eleven players take the field on defense.  The outcome of each play often depends upon the performance of most, if not all, of the 22 players on the field.  Yes, we track how many passing yards Favre has thrown in his career.  And we note his interceptions.  But none of these statistics are created by Favre alone.  Each completed pass is completed to another player.  For that completion to happen, receivers must run their routes and line-man must block.  The play itself must be designed and taught by the coaching staff.  Even on interceptions, one can look at the performances of line-man and receivers (and perhaps coaching) when assigning blame.

The importance of teammates becomes quite clear when we look at the consistency of quarterbacks across time.  Again, I turn to the point I made in the post detailing the New QB Score.

The page detailing the final QB Score rankings for 2006 begins with the following disclaimer: “As we note in the book, statistics in the NFL do not necessarily represent a quarterback’s ability. So these evaluations should not been seen as conclusive evidence that one quarterback is “better” than another.”

Quarterbacks (and running backs) are quite inconsistent across time (unlike basketball players who are quite consistent across time).  This point about quarterbacks was made in the following posts:

Consistent Inconsistency in Football

Football Outsiders and QB Score

The Value of Player Statistics in the NFL

In The Wages of Wins we argue that the inconsistency on the gridiron is a reflection of the impact teammates and coaches have on player performance in the NFL.  A quarterback might have “good” statistics because he is “good”, his teammates are “good”, and/or he plays in a “good” system. The statistics cannot tell us who is ultimately responsible for the outcome we observe.  Hence the primary purpose of tracking statistics – it allows us to assign responsibility for outcomes – is not achieved in football.  This observation should always be kept in mind when we look at statistical evaluations of football players.

By the way, of the three sports (baseball, football, and basketball), basketball players post the most consistent statistics across time.  And that is why I am quite comfortable assigning credit to individual NBA players for their statistics.  Perhaps another post on this topic would be a good idea in the future.

– DJ

Update: Noah noted in the comments that NFL.com has game logs, which do tell us Favre’s fumbles lost for 1991-1993.  I estimated that Favre lost 7.4 fumbles in these years.  NFL.com tells us that he actually lost 10.  With this data incorporated, Favre’s career wins fall from 41.5 to 41.3.  Thanks to Noah for alerting me to this data source.

I should also note that Brian, from bbnflstats.com, offers a good comment as well.  Hopefully my response is as good. 

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