Several threads have discussed the evaluation of QBs. Clarence Beeks provided some good stuff in “Terrelle Pryor 2008 Statistics”.
Some have suggested the NCAA Passer Rating Formula is viable to evaluate QBs. Bottom Line – It is NOT meaningful. Here’s why.
The Formula contains these 4 components that are summed together:
1) Percent Complete X 100
2) Yards Per Attempt X 8.4
3) Touchdowns Per Attempt X 330
4) Interceptions Per Attempt X – 200
Percent complete is an important indicator for QBs so it would obviously be included in any analysis. It ends up to be about 1/3 of the total number.
Yards per attempt are also important and the 8.4 multiplier doesn’t bother me (even though I have no clue where it came from). I changed the multiplier to 5.0 and 10.0 and it did have any dramatic impact on the order of QBs. With the 8.4 multiplier, most good QBs have a higher score for YPA than CMP%. This is the first strike against the formula. Do we all agree that YPA is more important than CMP%? I sure don’t. The QB has a lot more control over CMP% than YPA.
The next two (TD & INT) are inexplicable to me. Somehow TDs are deemed 65% more important than INTs. The QB has a lot more control over INTs than TDs. And, INTs are a turnover – the one stat that everyone agrees is the primary indicator of which team wins or loses a game. This is strike two.
Fumbles lost by QB is not included at all. Strike three.
TDs scored rushing by QB is not included. Strike four.
QB rushing yards are not included. Strike five.
Total yards are not included at all. Thus, if 2 QBs have everything else equal but one QB has twice the attempts and twice the total yardage, they are considered equivalent QBs. Strike six.
Final note (and yes, some may consider this anecdotal), here is the list of Michigan’s 10 greatest QBs since 1949 if NCAA Passer Formula is used:
Elvis Grbac 148.1 (6460 Total Yards)
Jim Harbaugh 145.6 (5449 Yds)
John Wangler 145.2 (2994 Yds)
Todd Collins 145.0 (5858 Yds)
Michael Taylor 141.6 (2194 Yds)
Drew Henson 140.8 (2946 Yds)
Tom Brady 136.4 (5351 Yds)
Chad Henne 133.9 (9715 Yds)
Brian Griese 131.4 (4383 Yds)
Rick Leach 130.0 (4284 Yds)
If you think this list is correct (sorry #8 Henne), then the formula works for you.