How a rookie’s 40-yard dash time can predict NFL successKevin Day, August 21st, 2008
One of the most valuable articles in Pro Football Prospectus 2008 describes a new way to predict the future performance of rookie running backs.
In “Five Seconds Can Be a Lifetime,” Bill Barnwell describes a simple equation that combines a rookie’s weight and 40-yard dash time into one number that is better than any other number in predicting if that running back will be a success in the NFL.
He calls that number the Speed Score and calculates it with this equation:
The faster a player’s time, the higher the Speed Score. Also, if two players run the exact same 40 time, the one that is heavier gets a higher score because he had to run the time with more weight on his body.
When Barnwell looked at past rookies and how they later performed, he found that many successes had a speed score greater than 100 and many busts had speed scores less than 100.
I don’t want to give away too much, but when you look at the list of players it picked to succeed versus those it didn’t is pretty impressive. It is slightly biased because a 40-yard dash time that isn’t weight adjusted is already a good indicator of success. However, their statistics show that the speed score is slightly better than the 40-time alone.
Can you guess which rookie this year posted the highest speed score at the combine? You’ll have to buy the book to find out, but I will say that it wasn’t McFadden.