Recall that we are interested in seeing whether combine performance, draft position,
opportunities as a rookie, and offensive performance as a rookie are related to each other. To do this, we used combine results, draft position, and first year NFL statistics for running backs and wide receivers from 2008 to 2012. More specifically, we explored four relationships within the running back and wide receiver data:
(1) Combine performance should predict where rookie running backs and wide receivers are taken in the draft.
Relationship 1: Combine Performance and Draft Position We set out to build a statistical model3 to show which of the six combine events (40-yard dash, bench press, cone drill, shuttle drill, vertical jump, and broad jump) best predict players’ draft position. We found that three of the six combine events together predict where a RB was drafted: 40-yard dash, cone drill, and shuttle drill. In fact, these three combine drills together mathematically account for 20% of the reason why a player is drafted with a certain pick.
For wide receivers, only one combine metric – broad jump – accurately predicts draft position (broad jump accounts for 8% of the reason why a player is drafted a certain pick). In other words, the farther a wide receiver broad jumps, the higher he will be drafted. This relationship seems to hold true for Jon Baldwin, who posted one of the longest broad jumps at the 2011 combine.
Figure 1 illustrates the relationship between what our statistical model would project as a player’s draft position and where that player was actually taken in the draft. For many players, this model is spot on. In 2008, the Bengals drafted wide receiver Jerome Simpson 46th overall. Based solely on his combine broad jump, our statistical model predicted that he would be drafted 49th. While not every prediction is this closely aligned with their draft position, the statistical analysis does provide some statistical insight into the logic of coaches and scouts observing the combine.
Overall, it seems that draft position does have a lot to do with how many opportunities a player gets as a rookie. For running backs, draft position is clearly related to the number of opportunities that a rookie received, as running backs who are drafted higher get more opportunities. Jahvid Best fit this mold – taken in the late first round, the Lions expected him to contribute right away. Best earned 245 combined rushing and receiving attempts in his first full season as the starting running back. From 2008 to 2012, the average running back drafted in the first round got an average of 171 rushing and receiving attempts their rookie year. Clearly, the Lions were excited about Best’s potential, and awarded him with plenty of opportunities.
Relationship 3: Opportunities and Offensive Performance Does the more opportunities a rookie running back or wide receiver get – both rushing and receiving – equate to better offensive production? To explore this, we created a hybrid metric of offensive performance, composed of the average of all receiving and rushing yards, also known as the average yards from scrimmage. This measures the offensive impact a player makes each time they touch the ball.
Best had the fastest 40 yard dash of all running backs at the 2010 NFL draft. He finished with the 11th best offensive performance for all rookie running backs selected in the first round from 2008 to 2012. Best’s offensive performance was 4.27 yards per touch. The average offensive performance for all first round rookie running backs from 2008 to 2012 was 4.75 yards (or 4.4 yards if you remove Felix Jones who posted 8.4 yards per opportunity).
We then looked at the relationship between broad jump and wide receivers’ first year offensive performance. Again, we found no relationship between the two. The length of a wide receiver’s broad jump at the combine had no bearing on his offensive performance as a rookie.
Read Part 3: http://www.burkmont.com/2014/05/the-nfl-combine-do-big-investments_8.html