Tom Brady, Bill Belichick, and ceteris paribus
Sports rarely gives us such a clean way of determining value
Economists obsess over the idea of ceteris paribus. It’s a Latin phrase that basically means “all else being equal”. In any good applied economics paper, a good chunk of the approach section will be devoted to trying to convince the reader that ceteris paribus has been achieved.
What exactly is ceteris paribus? Consider a simple example. Say that Oregon establishes a new tax on cigarettes and a researcher wants to figure out how that tax increase changed the percentage of people who smoke. The naïve approach would be to compare smoking rates before the tax and after the tax and attribute any change in smoking rates to be the result of the tax. The problem with this is the underlying assumption: that smoking rates would have been stagnant absent the tax. Now, if Oregonian smoking rates had remained stationary for decades, or if researchers are only comparing the month before the tax went into effect to the month after, then that assumption might be acceptable. If the smoking rate in Oregon has shown variation or the time window is several years, then that assumption is inaccurate. (In a turn of phrase that I always found slightly condescending and totally hilarious, economists will refer to unrealistic conditions as “heroic assumptions”.)
A researcher then needs to find some alternative to a before vs. after comparison. This is where modern econometrics comes in. One simple solution would be to compare Oregon to a similar state that didn’t have a tax change and look at how smoking rates in Oregon changed to that control state. The natural fit here would be Washington, which has a similar population, density structure (one large city with a lot of rural space), demographics, etc. If Washington’s smoking rate decreased by two percent over the study period, and Oregon’s decreased by three percent, then one can claim the net effect of the cigarette tax is a one percent decrease.
The underlying assumption is that everything is the same in Oregon and Washington except the cigarette tax, and thus any change in results can be attributed to said tax. One could say that the tax increase, ceteris paribus, decreased smoking rates by one percent. Now, of course there are problems with this. Oregon and Washington may be similar, but they aren’t identical. Washington has a larger population than Oregon, and Seattle is a bigger class of city than Portland. Washington is also significantly more racially diverse. So is the approach valid? The answer is more one of judgment than objectivity. The author of a study will claim validity and try to convince journal reviewers the conclusion is valid. If the reviewers agree, the paper gets published. The key fact is that ceteris paribus is rarely achieved beyond all doubt. Instead, economists try to find the best control group they can and go from there.
Sports is another field in which assigning cause and effect is difficult, especially when trying to determine the value of an individual player or coach. Many variables are changing all the time. Baseball can do an ok job determining ceteris paribus effects because the sport is essentially a series of one-on-one competitions between pitchers and batters. In other sports, however, many players are constantly interacting with each other. Even with great players, there’s always a question of how they would have done on a different team. Michael Jordan is considered by many to be the greatest basketball player of all time, but his few detractors will point out that he did conveniently have Scottie Pippen, who is one of the 50 greatest players in NBA history, as his teammate for all six championship seasons. Of course, the counterargument to that argument is that Scottie Pippen was so good because he played most of his career with Jordan, and thus was not the focal point of any defense. On top of that, one has to wonder how well Jordan or Pippen would have done without Phil Jackson, a man who literally has more championship rings than fingers.
Then consider football. On top of the standard difficulties of assigning value that any sport has, football has an additional complication. Each organization is essentially made up of two different teams: the offense and the defense. The occasional player may take snaps for both sides, but they are essentially separate entities. Thus, the best offense in the world may not do that well because of a bad defense, and vice-versa. Imagine if baseball teams had not one but nine designated hitters. That’s how football works.
Thus, with any great player or coach, it is hard to determine value. To take one example, my home city of Chicago lionizes (Bearizes?) Mike Ditka. He is the only coach to win the Super Bowl with the Chicago Bears. For that, he has become a lifelong celebrity. As more than a few neutral commentators have pointed out, however, he may be overrated. He undoubtedly had one of, if not the, greatest defense ever assembled. To have a team with that much talent and to only win one Super Bowl (and only play in one) is not that great of a resume. Even at the time, some believed that the defensive coordinator, Buddy Ryan, should have been given the lion’s (bear’s?) share of the credit. I disagree with this notion because while Ditka only went to one Super Bowl, his teams won at least 10 games all but one season between 1984 and 1991. Since the NFL playoffs are single-elimination, there always going to be a great deal of luck. Just look at Tom Coughlin, who somehow won two Super Bowls over ten years despite having a regular season win percentage of 53 percent.
You can play this type of game with any player or coach. How does Peyton Manning do without Reggie Wayne as a receiver? How does Reggie Wayne do without Peyton Manning as a quarterback? How many rings would Barry Sanders have if he was on any team other than the Lions? Would Dan Marino have won multiple Super Bowls with a better team around him? There’s no way to say.
That brings us to the New England Patriots. For 19 years they were the undisputed kings of the league. Nine Super Bowl appearances. Six wins. Seventeen divisional titles. An unbelievable amount of success. Behind all that success was a lot of players, coaches, and organizational staff. But the unquestionable keys to success were quarterback Tom Brady and head coach Bill Belichick. The two unlikely partners were together for the entire run. Normally, it would be impossible to determine who was more responsible for most of this success. In this one case, however, fate lent a hand. In 2020, Tom Brady moved to the Tampa Bay Buccaneers, and Belichick stayed with the Patriots.
The results couldn’t have been more different. Brady led a franchise that hadn’t had a winning season in four years or made it to the playoffs in over a decade to a Super Bowl victory in his first season. The next was almost as good, with the Buccaneers tallying a 13-win regular season before narrowly losing to the eventual champion Los Angeles Rams in the second round of the playoffs. Brady would have one lackluster final season before hanging up his cleats for good after the 2022 season. Since then the Buccaneers have been uninspiring.
Belichick, on the other hand, did not have the same success. Four years without Brady produced three losing seasons and one first-round playoff loss. Looking at Belichick’s total record without Brady is even worse. He coached 11 seasons without Brady. Five with the Cleveland Browns, one season when Brady was a rookie and not starting, one season where Brady was hurt, and four after Brady moved to the Buccaneers. Over those 11 seasons his teams compiled 81 wins and 95 losses for a winning percentage of .460. That is not great. Two playoff appearances, but not a single win.
You will never have ceteris paribus in sports, but this is about as close as you can get. I don’t think there’s any argument that Tom Brady is the greatest of all time. He has no equal or near-equal. Belichick, on the other hand, is tougher to declare. I think his 11 mediocre seasons without Brady knock him firmly out of the greatest of all-time conversation. With that said, he still won an astonishing six Super Bowls, and coached the greatest single team of all time, the 2007 Patriots. Belichick should get credit for being a great coach, in the idea that there are always 2 to 4 great coaches in the league at any one time. It wasn’t all Brady, but it’s hard to see how he doesn’t deserve most of the credit.