Almost half of the 256 games played in the 2010 regular season were decided by seven points or less. 121 games to be exact. A quarter of the games (65) were decided by 3 points or less.
In many games, the outcome was determined by a single play. Cowboys fans know this all too well: from holding calls though stripped balls to missed extra points, it felt like the Cowboys got the short end of the stick quite a lot in 2010. And the Cowboys' record in close games confirms that.
Seven Cowboys games were decided by 3 points or less, with six of those coming in the last six games of the season. The Cowboys finished 3-4 in those close games. Only the Redskins had more of these close games (9) and finished with a 4-5 record. So does this mean the Cowboys were luckier than other NFL teams? Or unluckier?
Good news for everybody who's ever pondered this conundrum: a little bit of simple math can help us find the answer.
We have at our disposal a nifty little stat called the Pythagorean Formula. The formula was originally developed by the godfather of baseball stats, Bill James, who surmised that a team's true strength could be measured more accurately by looking at points scored and points allowed, rather than by looking at wins and losses.
The formula was later revised by Daryl Morey (then a statistician for STATS, Inc., since 2007 General Manager of the Houston Rockets) , who developed the following NFL version of the formula:
Points Scored2.37
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Points Scored2.37 + Points Allowed2.37
The formula calculates the projected wins for a team based points scored and points allowed. Applied at the end of the season, it can tell you which teams won or lost more games than they "should" have. Teams that won more games than the formula provides for can be considered lucky, teams that lost more games than projected are unlucky.
Here's the full list of teams ranked by their level of luck:
| Team | Points scored |
Points allowed |
Net Points |
Wins | Projected Wins |
Variance |
| Atlanta | 414 | 288 | 126 | 13 | 11.2 | 1.8 |
| New England | 518 | 313 | 205 | 14 | 12.2 | 1.8 |
| Jacksonville | 353 | 419 | -66 | 8 | 6.3 | 1.7 |
| Chicago | 334 | 286 | 48 | 11 | 9.4 | 1.6 |
| Seattle | 310 | 407 | -97 | 7 | 5.5 | 1.5 |
| Baltimore | 357 | 270 | 87 | 12 | 10.5 | 1.5 |
| Tampa Bay | 341 | 318 | 23 | 10 | 8.6 | 1.4 |
|
New York Jets |
367 | 304 | 63 | 11 | 9.7 | 1.3 |
| New Orleans | 384 | 307 | 77 | 11 | 10.0 | 1.0 |
| Indianapolis | 435 | 388 | 47 | 10 | 9.0 | 1.0 |
| Kansas City | 366 | 326 | 40 | 10 | 9.0 | 1.0 |
| Miami | 273 | 333 | -60 | 7 | 6.1 | 0.9 |
| New York Giants | 394 | 347 | 47 | 10 | 9.1 | 0.9 |
| Arizona | 289 | 434 | -145 | 5 | 4.4 | 0.6 |
| Philadelphia | 439 | 377 | 62 | 10 | 9.4 | 0.6 |
| St. Louis | 289 | 328 | -39 | 7 | 6.8 | 0.2 |
| Washington | 302 | 377 | -75 | 6 | 5.9 | 0.1 |
| Minnesota | 281 | 348 | -67 | 6 | 6.0 | 0.0 |
| Pittsburgh | 375 | 232 | 143 | 12 | 12.1 | -0.1 |
| Carolina | 196 | 408 | -212 | 2 | 2.3 | -0.3 |
| Buffalo | 283 | 425 | -142 | 4 | 4.4 | -0.4 |
| San Francisco | 305 | 346 | -41 | 6 | 6.8 | -0.8 |
| Oakland | 410 | 371 | 39 | 8 | 8.9 | -0.9 |
| Dallas | 394 | 436 | -42 | 6 | 7.0 | -1.0 |
| Cleveland | 271 | 332 | -61 | 5 | 6.1 | -1.1 |
| Houston | 390 | 427 | -37 | 6 | 7.1 | -1.1 |
| Denver | 344 | 471 | -127 | 4 | 5.1 | -1.1 |
| Detroit | 362 | 369 | -7 | 6 | 7.8 | -1.8 |
| San Diego | 441 | 322 | 119 | 9 | 10.8 | -1.8 |
| Cincinnati | 322 | 395 | -73 | 4 | 6.0 | -2.0 |
| Green Bay | 388 | 240 | 148 | 10 | 12.1 | -2.1 |
| Tennessee | 356 | 339 | 17 | 6 | 8.4 | -2.4 |
Let's look at the Cowboys in a little more detail. The Cowboys ranked 7th in the league in points scored with 394, but ranked 31st in points allowed with 436. Their actual record was 6-10, and the formula projects their record at 7-9. So it would be fair to say that the Cowboys less lucky than most teams. Our division rivals on the other hand had luck on their side, the Redskins (barely), Eagles and Giants all came out ahead of their Pythagorean projections.
I originally looked at Pythagorean wins after week two of last season in this post. At the time, the Cowboys were on course for a 4.5 win season, so after only two weeks, the formula was already accurate to within 1.5 games of the final record. Mind you, the formula jumped to 8.1 the next week, so while it's not perfect by any means, it's still an interesting approach.
People kept asking me during the season for updated Pythagorean projections, so here is how the Pythagorean wins developed for the Cowboys week by week:
| Week | Opponent | Projected Wins |
| 1 | @ Washington | 2.9 |
| 2 | Chicago | 4.5 |
| 3 | @Houston | 8.1 |
| 5 | Tennessee | 7.3 |
| 6 | @ Minnesota | 7.2 |
| 7 | New York Giants | 7.0 |
| 8 | Jacksonville | 6.1 |
| 9 | @ Green Bay | 4.7 |
| 10 | @ New York Giants | 5.5 |
| 11 | Detroit | 6.4 |
| 12 | New Orleans | 6.4 |
| 13 | @ Indianapolis | 6.7 |
| 14 | Philadelphia | 6.7 |
| 15 | Washington | 6.9 |
| 16 | @ Arizona | 6.9 |
| 17 | @ Philadelphia | 7.0 |
As for the other teams, the formula suggests that the Patriots and Falcons were the luckiest teams, both recording about two more wins than their points total would suggest.
At the other end of the spectrum there are five teams who all finished about two games lower than where the formula projected them. These were the unluckiest teams in the league last year - well, except for the Packers. I had always wondered how a team that just barely managed to scrape together a 10-6 record and barely made the playoffs could then just walk over everybody en route to the Super Bowl. The Pythagorean formula provides at least part of the answer: they were simply unlucky.
These types of rankings tend to change significantly from year to year. Some people attribute this to Lady Luck coming or going, others talk about regression to the mean, others yet couldn't care less about some fancy formula. But one thing looks pretty sure: things can only get better for the Cowboys.