THE BLOG
12/01/2009 12:50 am ET | Updated May 25, 2011

Pass the Victory, Please

Does throwing for over 300-yard mean success for the passer’s team?  It does, especially lately, according to an article by Michael David Smith in the Wall Street Journal
Recently, the winning percentage for teams with a 300-yard passer is on
the rise.  Mike Martz reasoned that teams are now using the pass to get
ahead and not just passing to desperately catch-up when trailing,
"Teams are throwing because they want to now, not because they have
to," Martz told The Journal.

However,
looking at the outcome for 300-yard passers does not tell the whole
story.  We would expect those throwing for big yardage to have a good
chance of winning—this makes the sub .500 winning percentage in some
years quite surprising.  To really confirm Martz’s story, we need to
consider how teams fare when a quarterback attempts a certain number of
passes.  If teams really are passing more by choice, we would expect to
see improved outcomes not just when a quarterback passes over 300
yards, but also when they attempt a certain number of passes.  The
incidence of 40 attempts is relatively similar to the frequency of
300-yard passers, so it seems like a convenient starting point.

Using Pro-Football-Reference’s fantastic new game index tool, I was able to confirm Smith’s numbers and also check to see whether teams passing 40+ times per game have fared better in recent years.  I also looked to see whether the incidence of 40+ attempts/300+ yards has increased.  One note is that all numbers here are based on individual stats, so teams that have 300+ yards or 40+ attempts with multiple quarterbacks do not make the list.  The statistics include games played this Thanksgiving, but not this past weekend.

For the visual people out there:

So while there is a noticeable upward trend of 300+ yard passers
winning, the same cannot be said of quarterbacks that attempt 40+
passes.

Unsurprisingly, there is a huge correlation (r^2=.49) between the
win percentage for 300+ yard passers and 40+ attempt passers.  There is
a lot of overlap between these groups.  389 players appear on both list
(i.e. 46.5% of those who attempt 40+ passes also throw for 300+ yards
and 54.7% of those who throw for 300+ yards also attempt 40+ passes). 
Of quarterbacks who throw for 300+ yards and attempt 40+ passes, the
win percentage is .382 (much higher than the .190 rate for those who
throw 40+ passes and less than 300 yards) .  Those who throw for 300+
yards and attempt less than 40 passes win at a .764 rate.  Throwing
lots of yards=good.  Throwing lots of passes=bad.  Doing both=not great.

The
win percentage for quarterbacks who throw for 300+ yards and attempt
40+ passes does appear to be on a bit of an upward trend lately,
however, nothing historically surprising.

This year does not seem to represent any major shift in the way the
game is played.  Yes, throwing 300 yards is good.  It is very
advantageous to do so with less than 40 attempts.  Much of the success
of this year's 300+ yard teams is driven by the fact that there are
more than usual who are gaining 300+ yards without attempting over 40
passes. 

This season alone there have been 35 quarterback games
with a 300 yard passer doing so under 40 attempts (10.7% of all
quarterback games).  In previous seasons, this happened at a frequency
of 4.7%-7.2%.  One thing to keep in mind is that the numbers may be
artificially high right now since later in the season, as the weather
gets colder, passing games may be grounded.

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