My theory was that yes, more and higher draft picks typically mean increased success to their team. Keep in mind I am talking about the draft picks in the abstract--not necessarily the players themselves but simply the selection positions. (Credit goes to Doug Drinen who originally attempted to use regression to test the connection between draft points and wins.)
To test the theory, I created a variable called DELTAWINS which is change in total wins from year to year for each team from 2002-06. This was my dependent variable. For my independent variables I used conventional draft pick point values. In other words, I used each team's total draft points from the immediately preceeding draft to see if it significantly correlated with an improvement in each team's season win total.
Simply put, higher draft picks--and more of them--should lead to more wins the following year. If so, the regression coefficient for conventional draft pick point values would be expected to be positive and significant. Actually, the coefficient is 0.0022 and is strongly significant, with an r-squared of 0.26. (The constant for the equation is -4.2.)
The team with the #1 pick in each round, the team with the worst record, has a total of 3957 points. It would be expected to improve by:
-4.2 + 0.0022 x 3957 = 4.6 wins.
The team with the #32 pick in each round, the Super Bowl champion, has a total of 1020 points. It would be expected to get worse by:
-4.2 + 0.0022 x 1020 = -1.9 wins.
However, the regression has problems. First, the distribution of draft points is not normal--a bell curve. (Someone who points this out is not normal either, I admit.) It is a gamma distribution. One of the prerequisites for linear regression is that the variables's distributions are approximately normal.
For now, however, we'll ignore that problem because there is a bigger one. NFL teams with losing records tend to improve and ones with winning records tend to get worse. The draft may be one reason, as my hypothesis states, but there are others such as "strength of schedule" or salary cap boom/bust cycles--more on the other possible reasons later. For now, we'll accept that the model needs to account for a teams previous W-L record.
Do Draft Picks Equate to Wins? 1
By
Brian Burke
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