Determining the NFL’s true home-field advantage
I get as many requests from readers to update this article as anything else I do each year. And I know why. One of the most important and debated factors in handicapping college (and pro) football games is in determining how much weight to be given to home-field advantage. The numbers have varied greatly in recent years, what with empty or partially filled stadiums because of the COVID-19 pandemic. Now that we’ve had a few years in the “return to normal,” has anything changed? In my opinion, there’s never a bad time to revisit the subject of home-field advantage, specifically, what it is worth from a quantitative perspective.
A few of the things I set out to find when breaking down my data over the last 3-1/2 seasons in college and pro football were 1) Has home-field advantage picked up since COVID stopped wreaking havoc on football? 2) Have oddsmakers adjusted appropriately for any changes? 3) Have any specific teams at the various levels of football set themselves apart in terms of home-field performance?
In my history of oddsmaking, and since doing the strength ratings for VSiN, I have always found that one of the most important factors in analyzing teams’ strengths in football, or any other sport, is determining how much home-field advantage to assign. I remember many years ago always hearing that “3-points” should be the typical HFA. I also know that there are handicappers that do it from a general sense, issuing a standard 2-3 points depending upon how much they value that particular factor. Others, such as myself, develop team-specific home field edges, assuming that there are naturally tougher environments than others across the football landscape. For that latter group, I am here to help in your quest to determine which teams deserve the most home-field advantage points in pro football.
Let’s face it, we almost have to do the team-specific method as bettors because there are many reasons why certain teams have more definitive home-field advantage than others. Among these are weather, field surface as it fits the roster, crowd capacity/enthusiasm, confidence level of a team, and perhaps even distractions available to a visiting team while there. The degree to which these factor into play can also waver from season to season based on how a team is faring. I am 100% positive that there is no way that every team’s advantage is the same. Judging home field edges as equal across the board can lead to mistakes and either missed or lost betting opportunities. I am also 100% sure you will be convinced after I share my quantified performance results.
To determine which teams hold the best true home-field advantage in pro football, I have taken the teams’ game logs at home since the start of the 2020 season, or essentially the last 3-1/2 seasons. I compared their average power rating in those games to their opponents’ average power rating, using my actual logged numbers during that span for every game. This margin would be considered the amount they should have won or lost by when meeting on a neutral field or the expected margin. I then compared this amount to the actual point differential that the team accumulated in those games. Obviously, the teams that had a greater actual differential than expected differential played the “best” at home. In the NFL, the top home field edge belonged to Miami at +6, while the worst rating went to Arizona at -2.0.
In general, I believe most bookmakers will assign an average of about 2.0 points in the NFL. For the NFL the average over the last 3-1/2 seasons has been only 1.6. Obviously, this number takes into account the fan-less 2020 season still. That said, in the 2023 season, I am using a figure averaging 1.8 for true Home Field Advantage in the NFL.
One important thing to note, I don’t specifically assign the home field ratings in accordance with the order of the True Home Field Rating, as I also give strong consideration to the straight-up and ATS records, as well as the perceived difficulty of playing at a particular stadium. In recent years of this study, I have found that single games where a team won or lost big have tended to falsely impact the overall ratings. That said, new for 2023, I have removed the best and worst point spread losses for every team during the 3 1/2-year span from the calculations. These results are still noted in the SU and ATS records, but they didn’t factor into the formulas.
Let’s take a quick look at some of the other highlights I have found from my pro football home field advantage study, then stay tuned next week as I do the same exercise for road field performance.
NFL Home Field Advantage Study Highlights