Rest vs. Rust After Thursday Night Football

Andrew Mooney is the Co-President of the Harvard Sports Analysis Collective. He is a senior majoring in Social Studies, which is another way of saying he's an economics major. Andrew has worked as an analytics intern in the NFL for about two years, and previously wrote for the Stats Driven blog at Boston.com. He's a big fan of all Detroit sports, and he'll throw an octopus on your ice if you're not watching.

In struggling out of my bed at the witching hour of 8:00 am this morning, I had to wonder how much more equipped to tackle the day’s challenges I would be with an hour more of sleep. I then noticed that I wasn’t missing the tip of my finger, nor had I sustained a concussion the day before, incidents from which I would need significantly more than a week to recover. In this state of empathy, I couldn’t think of a more welcome time of the NFL season for a player than an extra day or two off.

Though I’m sure it provides players some much needed rest, it is not immediately clear what effect this time off has on performance. The qualitative cases for each side are pretty straightforward, and your grandfather used each of them liberally in instructing you in the wonders of sporting conventional wisdom. “Ah, they had an extra week to prepare AND get healthy,” he said knowingly after Washington’s 31-6 thrashing of the Eagles last season. “They just got rusty,” he told you after the Vikings fell to Chicago, 28-10, the following week. “What in the Sam Hill…” he muttered after the 49ers and Rams battled to a 24-24 tie.

Should You Bench Your Fumbling Running Back?

Sam Waters is the Managing Editor of the Harvard Sports Analysis Collective. He is a senior economics major with a minor in psychology. Sam has spent the past eight months as an analytics intern for an NFL team. When he is not busy sounding cryptic, he is daydreaming about how awesome geospatial NFL data would be. He used to be a Jets fan, but everyone has their limits.

When the Pittsburgh Steelers traveled to Cleveland in week 12 of last season, Rashard Mendenhall was the Steelers’ starting running back. Well, he was at first. Mendenhall fumbled on his second carry of the game, and Head Coach Mike Tomlin benched him immediately. On came backups Isaac Redman, Jonathan Dwyer, and Chris Rainey, who all fumbled and joined Mendenhall on the sidelines in quick succession. Out of untainted running backs to sub in, Tomlin looped back around to Mendenhall, who put the ball on the ground again. Mendenhall, of course, went right back to the bench, ceding his snaps to Dwyer and Rainey for the rest of the game. This was one of the more prolific fumble-benching sprees in NFL history, but we see tamer versions of this scenario all the time. Just look back to last season. David Wilson fumbled and Tom Coughlin actually made him cry. Ryan Mathews fumbled away his job to Jackie Battle. Tears and Jackie Battle - does any mistake deserve these consequences?

Deadspin/Slate: The Effect of Eliminating Kickoffs

The guys at Deadspin and Slate asked me to write up how Goodell's suggestion that kickoffs be replaced by punts would affect the game.

Here's the Slate link. Here's the Deadspin link.

...With proposed rule changes like these, I ask myself, "What if things had always been this way? Would we want to change from that to the way things are now?" If football didn't have the extra point—an odd play that's meaningless to game outcomes 99.9 percent of the time—would we want to invent one? Probably not.

In this case, if we'd always started the game with a punt, would we want to invent the kickoff? It's not so clear. With the yard line of the kickoff now at the 35 and as placekickers continue their trend of booting the ball farther, it won't be long before every kickoff is a touchback. The kickoff might soon become like the extra point—a boring formality...

I strongly recommend Keith's post on the subject too.

2012 Is the Year of the Comeback, So Far

I did some analysis for Judy Battista's recent New York Times article about the flurry of big comebacks this season. Don't overlook the article's graphic link to see some cool details.

Big, unlikely comebacks, in which teams overcame chances of winning of no better than 1 in 10, have occurred about twice as often so far this season as they did in the previous dozen seasons...Twenty percent of the games in the first seven weeks of the 2012 season had a comeback factor of 10 or more, meaning a team overcame at least a 1-in-10 chance of winning at some point in the game; only 11 percent of the games from 2000 to 2011 featured such turnarounds. Ten percent of the games this season had a comeback factor of 20 or more, meaning a team overcame at least a 1-in-20 chance of winning, but only 5 percent did so from 2000 to 2011.

You can find the biggest comebacks for any team or season using this tool.

Hail Mary Probabilities

Baseball guru Tom Tango noticed the WP graph for the recent Monday night meltdown had the Seahawk's chances at 0.01 prior to the game-ending play and thought it must be too low. He's correct.

There's a distinction between the WP model’s empirical methodology and its automatic output without any intervention or input from a human. When I do a detailed analysis for any specific play, I have the luxury of time and logic to dig directly into the data. The “auto” model that spits out WP estimates without any human input is based on lots of assumptions and interpolation on top of extrapolation etc. There are literally billions of combinations of game states (yd lines, downs, to go distances, seconds remaining, score difference, time outs). It’s just a matter of how much time I can put into coding the calculator to handle special cases like “a team's very last desperation play.”

With all the attention on that final play in the GB-SEA game, I thought it would be useful to look at Hail Mary success rates.

Football Island

Back in 1997 I was spent Easter Sunday with a good friend. His brother, who lived in the La Jolla area of San Diego, hosted us for dinner. On the drive up the La Jolla ridge overlooking the Pacific, my friend pointed over to the right side of the road and said, "That's Junior Seau's house." I caught a glimpse of number 55, along with what looked like a dozen family members filing out of a couple vans in front of the house. They were the largest human beings I had ever seen. The women were large, the men were unimaginably large, and even the children seemed enormous. Junior somehow appeared to be the runt of the family. I got the impression Samoans were all giants.

Last season there were 30 NFL players of Somoan descent, and 200 more playing Division IA college football. (Here's a list from 2008.) That's a lot of players from a group of people whose entire population could easily fit into an NFL stadium. Earlier this year 60 Minutes aired a profile on Samoan football, and if you missed it it's a great story. (I've embedded the clip at the end of this article. Edit--CBS has killed the link.)

Undoubtedly, the culture and character of the Samoan people are factors in their disproportionate level of success in football. But, as my drive through La Jolla suggested, hereditary traits may also play a role. Still, how can a single small island produce so many top players?

Should the Patriots Have Let the Colts Score?

After the Patriots' failed 4th down conversion attempt in the now epic game against the Colts, they wound up facing a Colts offense with a 1st down on the Pats' own 14-yard line. With 1:20 on the clock, the Patriots could have allowed the Colts to score an easy touchdown, yielding a 1-point lead, but giving the Patriots a shot to take the lead back with a possible FG drive. Or, they could have played straight defense, hoping to keep the Colts out of the end zone.

I'll take a look at league-wide averages, and then we can make adjustments from there. Against a team needing a TD, playing straight defense yields a TD about 62% of the time. This means the Patriots would have a 0.38 Win Probability (WP).

The Two-Minute Drill

In my recent posts on the Maurice Jones-Drew kneel-down and the Belichick 4th down decision I cited a few stats about how likely an offense that needs a touchdown to tie or win is to score one with about 2 minutes remaining in the game. Normally I like to back up obscure stats like that with some firmer context, and I was finally able to get around to it for these numbers.

The chart below graphs the percentage of time a team that needs a TD, defined as being down by 4 through 8 points, gets a TD on its current drive given a 1st down at various field positions with 2:00 +/- 15 seconds left. (I know that's quite the run-on sentence, but I don't know how else to say it.)