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The value of things: the Pythagorean theory

“Over a long enough period, the survival rate drops to zero.” —Tyler Durden

One of the characteristics of the typical sports fan is what I like to call “wishful thinking”. It’s a trap we all find ourselves in at one time or another. If we consider the Houston Texans, it follows us when we consider the transition from David Culley to Lovie Smith. The thinking goes, Culley was woefully incompetent, so even a switch to someone with basic skill should net two or three wins on its own.

The idea is not crazy at first sight. After all, we’ve all seen the Patriots and dolphins games last year. We saw the first half against Browns. A competent coach would have at least won the Patriots and Dolphins games. Suddenly a 4-13 season turns into a 6-11 season and you feel that much closer to respectability. From a certain point of view, it makes perfect sense.

The problem arises when we expect momentum from this development. Yes, you may have won those two games last season given the circumstances, but the mistake is to expect those circumstances to repeat themselves. Serendipity is not a bankable plan to move forward.

What exactly is the Pythagorean theory?

The Pythagorean Theory got its start in baseball. Honestly, it works better when you have more data points. The simple idea is that when you take the number of runs a team scores and the number of runs they allow, you can predict their record most of the time. In a baseball season, most teams will finish within five games of their projected record. When this is not the case, it becomes noticeable and worth considering for future performance. Obviously, we just transfer this to the number of runs a football team scores versus the number they allow.

The notion is based on a general premise that fans are wrong all the time. Conventional wisdom says that very good teams win the closest. Maybe they do. Yet this belief is based on bad assumptions. Very good teams blow their opponents out of the water. They can also gain closest, but gaining closest is not a bankable skill from season to season. After a long enough time, the survival rate drops to zero.

The brave people of Professional Football Reference actually calculates this for us. If we look at the Texans last season, we see that their expected record was 4.1 wins against 12.9 losses. In other words, they finished with precisely the exact record they were supposed to have based on how many runs they scored and how many runs they gave up. A comparison with the last eleven teams shows us something different than what the standings show us.

The first thing we need to do is make sure everyone is on the same page on all of our conditions. We have the records each team has finished with, followed by the number of wins their points differential would predict. The last statistic was the average margin of victory (or loss in most cases). If all goes according to plan, these margins should increase as records move further and further away from 0.500.

We see the Texans have the third pick in the draft and they had the third-highest margin of loss in the league. So, based on how many runs they scored and allowed, they ended up exactly where they should have been. Although this may not seem like a revelation, it does blow a hole in our wishful thinking that we had before.

Yes, David Culley could have led them to six wins had he been a reasonably competent trainer. However, those six wins would have been recorded as a bonus given the overall level of production we saw on the pitch. This sort of thing becomes more pronounced when looking at the seven winning teams on the roster. They vary wildly from five wins to nine wins in the expected records. The question is what a team does with this information.

A team like the Broncos chose to go for it. If this is truly a nine-win team masquerading as a seven-win team, acquiring Russell Wilson makes all the more sense. Raising a seven-win squad into the wildcard lineup sounds daunting. Going from nine wins to the wild card round or the division round is much less difficult.

Conversely, a team like the Falcons might be better off embracing a rebuild. If they are truly a five-win team masquerading as a seven-win team, they still have a long way to go to become a contender. Ditching an aging Matt Ryan makes more sense. That doesn’t explain why the Seahawks chose to drop their franchise quarterback, but sometimes the deals are too good to pass up.

Where does that put the Texans?

The key here is to recognize magical thinking when we see it. We need to temper our expectations. Will the Texans be a better team in 2022? In all likelihood, they will be considerably better. Will this result in a noticeable increase in earnings? This may not be the case. Part of the wishful thinking is that fans and analysts sometimes overlook the good luck that presented itself in the previous season.

Yes, they missed games against the Patriots and the Dolphins. Yes, they had other close games where things didn’t go their way. They also had games against the Titans and Chargers where things went as planned. They beat the Jaguars twice. Not only are these teams likely to be better in 2022, but the lucky rebounds the Texans got in those games can’t be bet anymore. Luck works both ways. Sometimes we catch ourselves dwelling on bad luck when we shouldn’t.

In practical terms, this means we need to be more sophisticated in how we measure success and failure. You can look at the record and eventually that’s what most people do. This is a bottom line business and this is the bottom line. However, we can tell a lot more when we look at the average margin of victory and loss. If they play closer games, they progress. We should focus more on Pythagoras than on random luck.