The NFL Draft has long been a subject of scrutiny for football fans and prospects alike. As a primary channel for player acquisition, draft behavior plays an essential role in roster construction and shapes the future composition of NFL franchises. While the selection process is largely secret, the outcomes can provide us some insight into the kinds of attributes teams value and aid us in evaluating the performance of different teams and general managers.
In 2005, Cade Massey and Richard Thaler published Overconfidence vs Market Efficiency in the National Football League, a seminal paper examining the decision making of NFL teams in the annual draft from 1988 to 2004. Massey and Thaler found significant evidence that NFL general managers fall prey to a number of biases in the player selection process, most notably overconfidence and the winner’s curse. Overconfidence, a term popularized by Kahneman and Tversky, refers to situations in which there exists a positive difference between a person’s subjective accuracy perception of their judgments and the true accuracy of those judgments. The winner’s curse is a phenomenon in auction theory suggesting that the winner of the auction is likely to end up paying more than the true asset value. Both of these biases are associated with one particular feature of team behavior over the years: overvaluation picks in early rounds of the draft and undervaluation picks in later rounds of the draft.
A likely explanation for these trends in pick valuation lies in a set of guidelines posited by former Dallas Cowboys head coach Jimmy Johnson. In the 1980s, Johnson developed a valuation system for draft picks based on previous trades, making explicit the values implied by prior transactions. This became known as “The Chart” and was quickly adopted by a number of teams as a general framework for constructing and assessing trade proposals. While teams adhered closely to this outline, The Chart was constructed as a descriptive tool, not a prescriptive one – that is, it was built to reflect the preferences that teams had demonstrated in the past, not necessarily optimal behavior.
Now, as teams become increasingly analytically driven, we could potentially expect biases to be addressed and behavioral tendencies to change. In a more recent edition of Massey and Thaler’s research, The Loser’s Curse: Decision Making and Market Efficiency in the National Football League Draft (2013), they find that the biases persist, but the past eight years have seen significant developments in team drafting approaches and attitudes toward analytics.
Even since the most recent Massey-Thaler paper, a number of other public analyses have been released, including FiveThirtyEight’s examination of team and GM consistency in beating the market (2014), Brian Burke’s update to the Massey-Thaler analysis in response to the new CBA (2016), and PFF’s exploration of surplus value by the PFF WAR metric (2020). We use a similar approach to derive pick value but expand on these analyses by digging deeper into behavioral tendencies and their associated results.
With variation in draft pick valuation as the backdrop, we attempt to formalize both macro- and micro-level team trends and outcomes. Each NFL franchise has a unique approach to constructing its roster via the draft, and in this report, we offer insights into what those strategies look like and how successful they have – or haven’t – been in the last decade. We include sections on general drafting success, player performance over/under expectation, high- vs. low-variance approaches, positional capital allocation, pick trading tendencies, and much more. The backdrop of these analyses is an expected pick value model we built using Pro Football Reference’s Approximate Value metric, which is defined by Pro Football Reference as “an attempt to put a single number on the seasonal value of a player at any position from any year.” We hope you enjoy it.
In order to generate a model of predicted draft pick value, we use two measures of value, both based on Pro Football Reference’s Approximate Value (AV): AV per season since draft (regardless of whether they played in a given year), and AV per game played. We split into two definitions of value because the former takes longevity into account by dividing total career production by number of potential seasons, and the latter looks exclusively at how well a player produced while he was on the field. Additionally, AV per season allows us to project total career production by multiplying the number of years since the draft times the projected AV per season. We find each of these definitions to have merit depending on the context of the analysis, and we will use them intermittently throughout this report. Importantly, we do not limit our player valuation to the first four years of a player’s career. While this approach has its limitations, we work under the simplifying assumption that each team/GM is making drafting decisions by total player value.
Pick value per game:
Pick value per season: