Correlation Between ADP and Team Win Percentage

Pickin' Winners

I recently took a look the average draft position of starting NFL players to see how much draft position really matters. To start, I took the most recent depth charts for each team per Ourlads.com and calculated the Average Draft Position (ADP) on a team and position basis.  In cases of major player injury, I assumed the draft slot of the player with the most snaps taken during the season to date. While (say it with me) correlation does not equal causation, there is plenty of food for thought.

Team Data

As you can see from the able above, there is no material correlation between draft position and win percentage with the exception of Defensive Tackle which has what could be considered a moderate correlation based on the data.   However, looking at overall correlation to the ADP for each team and then broken out by Offense and Defense, we find no ties.

Winners and Losers

When we breakout the numbers between teams with winning records and those with losing records, the picture is a bit different.

Results: Assuming 0.70+ is a strong correlation, selecting cornerbacks who were high draft picks seems to have an impact on win percentage.

Winners:  Winners have starting CBs with ADP of 2.97 however, correlation between CB ADP and win percentage is -0.75 meaning the relation is the lower the CB’s draft position the better the win percentage.

Losers:  The correlation in this case is based on losing record so the higher the draft pick the worse the win percentage, so the 0.71 correlation.

Based on the above, it could be that higher drafted CBs are not necessarily a driving factor in win/loss performance.  So, perhaps teams should curb the impulse to looks at better ADP CB selections.

Other factors:

Tight Ends:  Although TEs have an ADP of 4.27 for winning teams, there is a moderate correlation of 0.61 between win percentage and better ADP TEs.  This could be indicative of their being a shortage of difference making TEs so if teams cannot grab the top talent, they need not rush to fill a TE roster slot because the average ADP is in the second half of the draft anyway.

Defensive Tackle:  While the correlation is not as strong as that for TEs, at 0.49 for winners and 0.46 for losers, we see somewhat of a relationship between this position and win percentage. Winners pick up DTs with ADP of 2.77 while losing teams don’t quite value the position with ADP of 4.18.

Conclusion:  Cornerback is the most overvalued opposition and teams should consider that higher drafted CBs tend to result in lower win percentage based on the sample data here. This supports a prior analysis (found here) that found losing teams tend to overpay/overvalue CBs from a salary perspective.