Posted by Alex Bonilla on December 19, 2019
Baseball-Reference tracks various Hall of Fame predictor statistics such as Bill James' Hall of Fame Monitor and Jay Jaffe's WAR Score System. Basketball Reference also has a Hall of Fame Probability formula that we display on player pages and gives people a brief glance at where players stand based on their statistical case.
With the Pro Football Hall of Fame class of 2020 being debated this winter, we figured it was time to work up a Hall of Fame predicting formula for the NFL. We have devised a new HOF Monitor metric that we are deploying for Pro Football Reference beginning today! Here's a link to the quarterback HOF Monitor page, which also includes links to the other positions. Links to these tables will also appear under the Leaderboards and Awards section of player pages.
The base formula uses weighted Approximate Value (which is 100% of the player's peak year, 95% of their second-best year, 90% of their third-best, and so on) as a starting point. Bonuses are added for Pro Football Hall of Fame All-Decade selections, MVP awards, Defensive Player of the Year awards, first-team AP All-Pro selections, Super Bowls/titles, and Pro Bowls, in descending weights.
In addition, bonuses are added if a player has earned first-team All-Pro in over 33% of their seasons. This reflects the reputation boost afforded to players who led the league in short careers like Gale Sayers and Terrell Davis. For players not yet inducted, small bonuses are also added for semi-finalist and finalist appearances on previous HOF ballots, since that indicates that they've already been seriously considered.
On top of the base formula, there are statistical bonuses given depending on the position. For quarterbacks, wide receivers and tight ends there are different thresholds depending on the era they played in so as to narrow the gap between the depressed passing stats before 1980 and the explosion after that. For the full methodology, check out our PFR HOF Monitor explainer page here.
Similar to JAWS, a score of 100 is around the average modern-era HOF inductee for each position. All eligible players with a score over 120 got into the Hall of Fame fairly quickly, save for a few exceptions such as Willie Wood. A score of 150 would be a first ballot lock (sole exception of Alan Page who had to wait a year).
A score of 80 or above means they're a good candidate to eventually get in, or they’re the highest-profile borderline candidates. The absolute lowest score for HOF inductees would be 40, although most of these lower scoring Hall of Famers are courtesy of senior committee selections.
To get a sense of what absolute HOF locks look like in this system, here's a look at the highest HOFm scores:
As for the Centennial Class of 2020, here's how the HOF Monitor judged the modern-era semifinalists on the ballot, with this year's inductees marked with an asterisk:
We want to stress that this is especially meant to judge a player's chances of getting into the Pro Football Hall of Fame and not necessarily for "who is the best middle linebacker" debates. Many analysts agree that championships won reveal little to nothing about a player's individual skill, but it's certainly a factor that's taken into consideration by Hall of Fame voters. With that caveat out of the way, we're eager to hear feedback on the formula. Particularly, if you're interested in testing out your own tweaks, feel free to reach out to us via our feedback form and we can share the player data used to test out this system.