By now, you know about guest blogger Andrew Healy, an economics professor at Loyola Marymount University and author of today’s post. There’s now a tag at the site where you can find all of his great work. He’s back with a cap to his excellent series about playoff performance, and today’s post will not disappoint:
The Purple People Eaters never won a Super Bowl.
For the latter question, it turns out that it’s option D, none of the above. One mystery team has won four championships despite having had a pretty decent chance of never winning a single Lombardi. The most unlikely team never to win a Super Bowl turns out to be a team that lost “only” two Super Bowls, but that has led the NFL in DVOA four times since 1979.
To figure this stuff out, I’ve utilized DVOA ratings and estimated DVOA ratings to rerun the NFL playoffs. In the simulations, the slate is wiped clean, which means there’s no reason The Fumble or The Helmet Catch or The Immaculate Reception have to happen this time around.
In last week’s post, I went decade by decade to look at the best teams, and also those that most let opportunity slip through their fingers. Today, I bring it all together. I compare what might have been with what actually was for the NFL from 1950 to 2013. I’ll also hand out awards for the teams that were the most unlikely winners and the most unlikely losers of all time.
The ground rules for the simulations used to create these results are:
- 1) The playoffs were run under the rules in place in a given year. All of the results are based on 50,000 simulations run under those rules.
- 2) DVOA ratings are used for 1989 and estimated DVOA from 1950-1988. I created a betting line based on the DVOA difference between the teams, adding 2.5 points for home field. [1]The standard deviation of DVOA is about three times that of SRS, so I took the DVOA difference and divided by three to create the point spread. Again, thanks to Andreas Shepard for sharing the … Continue reading That line was used to simulate wins and losses.
- 3) I adjusted the DVOA estimates to account for AFL/NFL differences for the first four Super Bowls. Instead of being a pick ’em against Green Bay, the simulations make Kansas City a 7 point underdog against Green Bay were they to play in Super Bowl I. [2]If we look at 1970, the SRS for the former AFL teams averaged about seven points below the average for the NFL teams that year. We could use the actual point spread, of course, too. Those lines were … Continue reading
- 4) All franchises stay together through relocations with the exception of Cleveland. So the Titans and Oilers get grouped together as one franchise under Bud Adams, but the the original Browns get grouped with the current Browns, not Art Modell’s Ravens.
- 5) Pre-Super Bowl championships count, but only for the NFL. My condolences to the to the ’60 and ’61 Oilers, the ’62 Dallas Texans, the ’63 Chargers, and the ’64 and ’65 Bills.
The table below shows each team’s probability of winning no titles, its expected number of titles, its actual number, and the difference between its actual and expected number of titles. I calculated each of these quantities separately for the 1950-2013 period (in light blue) and for the years since the merger (in light red). Since the comparisons are somewhat different, I think it makes sense to hand out awards separately for both periods. Note that the table is sorted by the difference between actual and expected titles since the merger. That puts the Eagles on top (more to come on that distinction below).
The top row indicates that the Eagles had a 6% chance of no titles since 1950 and a 12% chance of no titles since 1970. Philadelphia has 2.4 expected titles since 1950, 1.93 of which come since 1970. In reality, the Eagles have won 1.4 fewer titles than expected over the last 64 years, and 1.93 fewer than expected since the merger.
| Team | P(0) | ExpT | ActT | Diff | P(0) | ExpT | ActT | Diff |
|---|---|---|---|---|---|---|---|---|
| PHI | 6% | 2.4 | 1 | -1.4 | 12% | 1.93 | 0 | -1.93 |
| MIN | 13% | 1.86 | 0 | -1.86 | 21% | 1.47 | 0 | -1.47 |
| SD | 26% | 1.21 | 0 | -1.21 | 26% | 1.21 | 0 | -1.21 |
| KC | 19% | 1.5 | 1 | -0.5 | 32% | 1.03 | 0 | -1.03 |
| HOU/TEN | 32% | 1.05 | 0 | -1.05 | 33% | 1.02 | 0 | -1.02 |
| RAM | 1% | 3.69 | 2 | -1.69 | 11% | 1.95 | 1 | -0.95 |
| BUF | 39% | 0.9 | 0 | -0.9 | 42% | 0.83 | 0 | -0.83 |
| CLE | 0% | 5.72 | 4 | -1.72 | 43% | 0.78 | 0 | -0.78 |
| CIN | 46% | 0.71 | 0 | -0.71 | 46% | 0.71 | 0 | -0.71 |
| NYJ | 44% | 0.77 | 1 | 0.23 | 52% | 0.62 | 0 | -0.62 |
| ATL | 54% | 0.59 | 0 | -0.59 | 54% | 0.59 | 0 | -0.59 |
| CHI | 3% | 2.7 | 2 | -0.7 | 15% | 1.58 | 1 | -0.58 |
| CAR | 65% | 0.4 | 0 | -0.4 | 65% | 0.4 | 0 | -0.4 |
| JAX | 67% | 0.36 | 0 | -0.36 | 67% | 0.36 | 0 | -0.36 |
| DET | 18% | 1.46 | 3 | 1.54 | 75% | 0.27 | 0 | -0.27 |
| DEN | 8% | 2.26 | 2 | -0.26 | 8% | 2.26 | 2 | -0.26 |
| CRD | 91% | 0.1 | 0 | -0.1 | 91% | 0.1 | 0 | -0.1 |
| TEX | 92% | 0.08 | 0 | -0.08 | 92% | 0.08 | 0 | -0.08 |
| MIA | 10% | 2.06 | 2 | -0.06 | 10% | 2.06 | 2 | -0.06 |
| SEA | 32% | 0.98 | 1 | 0.02 | 32% | 0.98 | 1 | 0.02 |
| TB | 50% | 0.64 | 1 | 0.36 | 50% | 0.64 | 1 | 0.36 |
| GB | 0% | 4.69 | 7 | 2.31 | 17% | 1.59 | 2 | 0.41 |
| NO | 59% | 0.5 | 1 | 0.5 | 59% | 0.5 | 1 | 0.5 |
| NE | 5% | 2.5 | 3 | 0.5 | 5% | 2.5 | 3 | 0.5 |
| BAL/IND | 1% | 3.66 | 4 | 0.34 | 26% | 1.27 | 2 | 0.73 |
| OAK | 4% | 2.86 | 3 | 0.14 | 9% | 2.23 | 3 | 0.77 |
| SF | 1% | 4.44 | 5 | 0.56 | 1% | 4.22 | 5 | 0.78 |
| WAS | 8% | 1.95 | 3 | 1.05 | 8% | 1.95 | 3 | 1.05 |
| DAL | 1% | 4.45 | 5 | 0.55 | 1% | 3.7 | 5 | 1.3 |
| RAV | 53% | 0.61 | 2 | 1.39 | 53% | 0.61 | 2 | 1.39 |
| PIT | 2% | 3.61 | 6 | 2.39 | 2% | 3.61 | 6 | 2.39 |
| NYG | 1% | 3.31 | 5 | 1.69 | 35% | 0.95 | 4 | 3.05 |
Let’s start with the Best Film Editing kind of awards before getting to the biggies:
Least Likely to Be Titleless since the Merger: San Francisco 49ers
They edge out the Cowboys in this category. Leading the league in DVOA five times, San Francisco had less than a 1% chance of winning no titles since the merger. It pays to have Joe Montana, Steve Young, Jerry Rice, and well, this list could go one for ages.
Least Likely to Be Titleless since 1950: Cleveland Browns
The Browns had just a 0.04% chance of winning no titles since 1950. It only feels like that might happen if we re-ran all the NFL seasons back to then. Between landing Otto Graham and Jim Brown, among others ,Cleveland was expected to win nearly five titles pre-merger… and less than one post.
Most Expected Titles since the Merger: San Francisco 49ers
San Francisco beats Dallas and Pittsburgh for the crown. The 49ers five championships isn’t far off from their expected 4.22 title. Remember, San Francisco overachieved in the 1980s and its teams have underachieved since then.
Most Expected Titles since 1950: Cleveland Browns
And this isn’t driven by The Fumble or The Drive, really. The Browns had 4.94 expected titles before the merger, more than any other team has had altogether since 1950. Overall, the Packers are a full title behind the Browns in expectation in second place. That would change, of course, if we included the ’30s and ’40s in this study.
Now for the big awards that get crammed into the last thirty minutes of the show:
Most Unlikely Loser since the Merger: Philadelphia Eagles
Despite leading the league in DVOA or estimated DVOA four times (1980, 1981, 2001, and 2008), and racking up 1.93 hypothetical Super Bowl wins, the Eagles have nothing to show for it. Philadelphia’s lead in this category is large in part because the Vikings’ 1969 season doesn’t qualify. Even if we include the entire Super Bowl era, however, the Eagles have the highest expected number of Lombardi trophies without actually owning any silverware. They have just a 12% chance of being without a Super Bowl title as of 2014.
Most Unlikely Loser since 1950: Minnesota Vikings
Chuck Bednarik, Tommy McDonald, and Norm Van Brocklin keep the Eagles out of this spot. The Vikings have 1.86 fewer championships than the 1.86 titles we would predict based on their strength and playoff positioning. In terms of championships left on the field, their nearest competitors are the Rams and Browns. The Rams won two championships, but were predicted to win 1.69 more. The Browns won four, but were predicted to win 5.72, the most of any team over the decades.
Most Unlikely Winner since the Merger: New York Giants
This one is kind of amazing. The Giants have just 0.95 expected Super Bowl wins, but have 4 actual ones. When looking at New York’s DVOA ratings and playoff seedings, there was a 35% chance of no rings for Big Blue. The Giants led the league in DVOA just once since the merger (1990) and only one more time (1959) overall. New York is held out of the top spot overall by their five championship game losses between 1950 and 1966. Despite all those losses, the Giants’ recent good fortune makes them #3 in titles above expectation going back to 1950.
Most Wins above Expectation since 1950: Pittsburgh Steelers
All the other headings fit the teams pretty well, I think, but this heading fits the Steelers better than the Most Unlikely Winner. The franchise has six Super Bowls, 2.39 more titles than expected. Pittsburgh’s ability to maximize opportunities in the 1970s and 2000s far outweighs the chances Bill Cowher’s crew squandered in the 1990s. The only team with more titles since 1950, the Packers, comes a close second here. Green Bay’s seven titles exceeded their expected number by 2.31.
Closing Thoughts
The two things that stand out the most to me are the ones at the opposite ends of the table. The Eagles having just a 12% chance of not winning a Super Bowl. The Giants having a 35% chance of winning none. Even after looking at a lot of numbers, I think it’s probably right that our perceptions of what might have happened get unavoidably biased by what came to pass. The 1986 Giants feel like a somewhat dominant team to me, at least, but I think the numbers are probably closer to the truth. It’s worth noting that they caught a huge break in avoiding the top team in 1986 by DVOA, in part thanks to Doug Flutie playing against Washington. [3]Yes, New York did beat the number 2 team in DVOA, the 49ers, 49-3 in the divisional round. And each of the Giants’ other championships were close calls that hinged on a single play. [4]The most obvious plays are the Roger Craig fumble (1990), the Helmet Catch (2007), and the Welker Drop (2011). Each of these may have been among the top twenty influential plays in NFL history, and … Continue reading Those anecdotes fit the numbers. The Giants are the most unlikely big winner since the merger.
It’s a closer call for the most unlikely loser since the merger, but the Eagles are a worthy winner (loser?) of the crown. The Vikings and Bills may have lost more Super Bowls, but the Vikings only led the league in DVOA once, while the Bills never did. On the other hand, the Eagles did it four times and that doesn’t even count the greatest defense in NFL history by DVOA (1991). If only they had even an average offense that year. For that matter, if only Donovan McNabb had moved less leisurely in Super Bowl XXXIX. If only the touchdown to Rodney Parker hadn’t been called back in Super Bowl XV. The near misses and the stats behind them make the Eagles the most unlikely loser since the merger. [5]Is all the pain and suffering since the merger karmic payback for this?
References
| ↑1 | The standard deviation of DVOA is about three times that of SRS, so I took the DVOA difference and divided by three to create the point spread. Again, thanks to Andreas Shepard for sharing the estimated DVOA ratings. |
|---|---|
| ↑2 | If we look at 1970, the SRS for the former AFL teams averaged about seven points below the average for the NFL teams that year. We could use the actual point spread, of course, too. Those lines were likely biased towards the NFL, although it’s certainly possible that the true spread was somewhere between 7 and 14. Anyway, it doesn’t make much difference if we use a slightly higher adjustment for the first four Super Bowls. And Jason’s series on the AFL/NFL remains excellent background reading. |
| ↑3 | Yes, New York did beat the number 2 team in DVOA, the 49ers, 49-3 in the divisional round. |
| ↑4 | The most obvious plays are the Roger Craig fumble (1990), the Helmet Catch (2007), and the Welker Drop (2011). Each of these may have been among the top twenty influential plays in NFL history, and they all went the Giants’ way. |
| ↑5 | Is all the pain and suffering since the merger karmic payback for this? |