Why NFL preseason win projections are (mostly) worthless

Our own Tony Catalina was innocently watching NFL Network’s GMFB on Tuesday morning and almost suffered a heart attack when a graphic dropped with the 2024 projected NFC playoff teams.

Thankfully, he recovered fast enough and had the presence of mind to take a screenshot of the offensive content being pushed by NFL Network.

Earlier that morning, our daily news post on Blogging The Boys featured two win projections for 2024. NFL.com showed an over/under for the Cowboys of 9.5 wins (and a second-place finish in the NFC East) and CBSSports.com had the Cowboys taking the NFC East crown ahead of the Eagles with a 10-7 record.

Few things get football fans more riled up at this time of year than win-total projections for the coming season, and the reaction to those projections is completely predictable.

One part of the fan base is outraged that anybody could think the Cowboys could come anywhere close to last year’s 12-5 team, another part is equally outraged that anybody could think the Cowboys could regress versus last year, a third part can’t understand how anybody could see much of a change in either direction.

But is getting worked up over those projections really worth it?

Over a decade ago, Brian Burke, formerly of Advanced Football Analytics and now working for ESPN, published two articles three years apart titled ‘Pre-Season Predictions Are Worthless’ and ‘Pre-Season Predictions Are Still Worthless’. Today I’m going to nerd out and use Burke’s methodology to understand whether anything has changed versus his assessments from 2007 and 2010.

To measure the accuracy of the projections at the time, Burke used a metric called mean absolute error (MAE). This is the average of the absolute difference between the projected wins and the actual win totals for a given year. If the MAE for a projection is 3.0, it would mean the projection was off by an average of 3.0 games in either direction. Obviously, the smaller the MAE, the better the prediction.

The win projections we’ll look at today are a collection of ‘expert’ projections for the last two years (ESPN 2022 & 2023, NFL.com 2022 & 2023, The Athletic 2022 & 2023) as well as the Vegas win total projections for 2022 and 2023.

For 2023, here’s how the experts ranked in terms of MAE for their projections.

  1. Vegas win projection: 1.86 MAE
  2. The Athletic: 1.93 MAE
  3. ESPN Analysts: 1.95 MAE
  4. Cynthia Frelund of NFL.com: 2.07 MAE

The expert predictions look to be pretty evenly matched, but for a sport that only has a 17-game season, being off by about two wins sounds like a lot. But is it?

To judge how good those values are, Burke proposed three very simple benchmarks to compare the results against:

1. Last Year: This simply uses the previous year’s win total as the projection for the current year.

2. The Coma Patient: Burke calls this the Constant Median Approximation system, or CoMA for short. This is a mindless 8.5-win prediction for every team.

3. Regression To The Mean: The assumption here is that teams tend to return towards a .500 record. Teams with a winning record tend to decline; teams with a losing record tend to improve. The formula I’ll use to calculate this is straightforward: Starting with 8.5 wins, I add 0.25 wins for every win above 8.5 from the previous year, or subtract 0.25 wins for every win below 8.5 from the previous year. For example, a 12-win team from 2022 would be predicted to have 8.5 + (12-8.5)/4 = 9.4 wins in 2023.

Here’s how the expert projections compare to those benchmarks over the last two seasons.

Source 2022 2023 Total
Expert
Projections
The Athletic 2.38 1.93 2.15
Vegas 2.48 1.86 2.17
ESPN 2.48 1.95 2.17
NFL.com 2.43 2.07 2.25
Data-based
Projections
Regression to the mean 2.48 2.04 2.26
Coma Patient 2.44 2.22 2.33
Last Year 3.00 2.59 2.80

Over the last two years, The Athletic beats out the Vegas projections by the narrowest of margins. Overall, the expert projections come out ahead of the data-based projections, but not by much – and the comparison is a coma patient and a simple regression to the mean.

When the simplest math produces almost the same level of accuracy as the expert projections, that raises some questions about the validity of the expert projections.

But don’t be fooled by these numbers and assume that the experts don’t know what they are talking about. If you’re so inclined, and think 2.2 is an entirely unimpressive number, try coming up with an algorithm that delivers better results. I promise you, that’s going to be very, very tough.

How do you account for a team like the Texans improving by seven wins from 3-13-1 in 2022 to 10-7 in 2023, and with a rookie QB to boot? Or the Vikings dropping by six wins from one year to the next?

The NFL is a closed system in which teams tend toward a .500 record, and a 9-8 or 8-9 record is mathematically the most likely outcome. In this system, every additional win above or below 8.5 wins is increasingly less likely, and projecting a team for a 12-5 or even 13-4 record is a risky move – or a bold move, depending on your point of view.

Yet many experts (NFL, ESPN, The Athletic, and Vegas are just the proxies used in this article for those experts) regularly pick teams to have very good or very bad records. Some of these experts use complex mathematical models, some use their expertise, many use a combination of both (some just hold a finger to the wind – but that’s a topic for a different day). But the fact that even the experts struggled to beat an algorithm based on the inherent parity of the league shows that their models and/or expertise may not be worth that much, though they are worth at least something.

But how much is something? That’s hard to say. Predicting the Chiefs for a double-digit win total in 2024 doesn’t seem like much of a stretch, given that they’ve had nine consecutive seasons with double-digit wins. But consider that outside of the Chiefs, there are only three teams in the NFL that have had double-digit wins in each of the last three seasons.

  • Bills: 5 consecutive seasons with double-digit wins
  • Cowboys: 3
  • 49ers: 3

All other teams are yo-yo teams that bounce up and down but haven’t shown the ability to get double-digit wins consistently. You might be high on the likes of the Ravens (13-4 last year), Lions (12-5), or the Eagles (11-6). But the odds that they’ll repeat as double-digit winners are slim.

Think of the NFL as a game of coin flip, where you get to flip the coin 17 times. If you had to put money on the outcome, the best bet would be a 9-8 or 8-9 result. Expecting a 12-5 result, while statistically possible, would not be very probable.

Coin flip odds based on 17 flips
4-13 5-12 6-11 7-10 8-9 9-8 10-7 11-6 12-5 13-4
1.8% 4.7% 9.4% 14.5% 18.5% 18.5% 14.5% 9.4% 4.7% 1.8%

And that’s also something to consider as you review the experts above, how much risk did they take with their projections? Here’s a simple look at the highest and lowest win totals in each projection:

2023 Projection
Low High “Stretch”
NFL 3.9 11.3 7.4
Vegas 4.5 11.5 7.0
The Athletic 5.7 12.0 6.3
ESPN 5.5 11.5 6.0
Regression to the mean 7.1 9.9 2.8

In this look, Cynthia Freelund has the highest level of risk baked into her projection, which might help explain why her MAE is lower than that of the other experts. ESPN and The Athletic took a more conservative approach to the win distribution, and Vegas might have the best mix of risk and accuracy, at least in our little exercise here.

For Cowboys fans, there is an upside to all of this. DraftKings are projecting Dallas as a 10.5-win team, Freelund likes the Cowboys for 9.2 wins, ESPN are projecting Dallas for 10.3 wins, and The Athletic has the Cowboys at an even 10.0 wins. Assuming another MAE of around 2.2 this year, the Cowboys are projected anywhere from 7.0 to 12.7 wins in 2024.

So sayeth the experts.

Which means there should be a result somewhere in that range that should suit just about every Cowboys fan.

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