Thursday, January 22, 2015

BS Journalism Watch: WSJ Edition

Just had to quickly note an absurd piece from the Wall Street Journal today, shockingly, it's not from the editorial page.

But I saw an article titled "Generation Y Prefers Suburban Home Over City Condo," and immediately alarm bells started going off in my head.


So I had to actually go read the article (which I guess was the point for - because I 100% didn't believe that headline. It just went against all my understanding of that generation...which I'm technically a part of.

Now, if it had been a study on a different age group I wasn't a part of, say, 'Study finds Boomers prefer Fat Chicks' - maybe I'd be a little skeptical, but give them more of a benefit of the doubt.

But this seemed highly unlikely, so I read, and yeah, turns out it's absurd on it's face. From the article...

LAS VEGAS—One of the hottest debates among housing economists these days isn’t the trajectory of home sales, but whether millennials, those born in the 1980s and 1990s, want to remain urbanites or eventually relocate to the suburbs.

Some demographers and economists argue that the preference of millennials, also called Generation Y, for city living will remain long lasting. And surveys of these young urban residents have tended to show that they don’t mind small living quarters as long as they have access to mass transit and are close to entertainment, dining and their workplaces.

But a survey released Wednesday by the National Association of Home Builders, a trade group, suggested otherwise. The survey, based on responses from 1,506 people born since 1977, found that most want to live in single-family homes outside of the urban center, even if they now reside in the city.

“While you are more likely to attract this generation than other generations to buy a condo or a house downtown, that is a relative term,” said Rose Quint, the association’s assistant vice president of survey research. “The majority of them will still want to buy the house out there in the suburbs.”

The survey, which was released at the association’s convention in Las Vegas, found that 66% want to live in the suburbs, 24% want to live in rural areas and 10% want to live in a city center. One of the main reasons people want to relocate from the city center, she said, is that they “want to live in more space than they have now.” The survey showed 81% want three or more bedrooms in their home.

I read that and was flabbergasted. Only 10% of people born after 1977 want to live in a city? And 66% want to live in the suburbs?

Think of all the people you know under only 10% of them currently live in a city? Do two-thirds of them say, "You know what would be better than all these restaurants, bars, and museums? A finished basement and a two car garage."

Sure - now that lots of us have kids - people are making the switch, but two-thirds??? Still doesn't make sense...until you read one of the later paragraphs...

"The survey results, though, could be skewed because they included only millennials who first answered that they bought a home within the past three years or intended to do so in the next three years."

So, in other words, this survey is total bullsh*t.

If you self select only people who have already bought homes or are planning on it soon...and you target a group of people that generally won't have the wealth to buy single family homes in urban centers, you can't be surprised when they all say they want to live in suburb or rural areas. Hell I'm surprised you found 10% that want to live in cities (must've been the reluctant soon-to-be-suburbanites)

The whole premise of the article is built on some BS data from a survey that is misrepresented and by the way, is conducted by a homebuilders trade group (who you think may have some incentive to convince people the suburbs is the place to be???)

That's some grade A crappy journalism -

Friday, January 16, 2015

Are NFL Teams Faking Injuries?

Given all the animated discussion over the Patriots tactics against the Ravens in their divisional round playoff game, I thought it would be as good a time as any to post some gamesmanship research.

If you read about the game – you know the Ravens were a bit upset with the Patriots usage of receiver eligibility to disguise their offense. The response from the Patriots was, well, Patriots-like. If it’s not against the letter of the law, it’s all good (unless it’s videotaping other teams, in which case even the law doesn’t matter).

Clearly, the NFL is a league where teams will look for any edge, even if it means pushing the bounds of fair competition.

So it’s with that issue in mind that I started digging into the possibility that players are faking injuries.

As a Philadelphia sports fan, I’m generally inclined to assume that my teams will ultimately lose, and so once the Eagles started running Chip Kelly’s offense, I was quick to accuse every injured defender a liar and a cheat (not to their faces of course).

The Eagles run a very high-tempo offense, one that doesn’t allow opposing defenses to leisurely make substitutions or get a full play clock to catch their breath. It’s a major feature of their strategy, and one that opposing teams would love to minimize, particularly if they aren’t well prepared for it.

One way to slow down the pace of the Eagles offense would be for an opponent to use their timeouts while the Eagles offense is in full-swing. But since a team only has three timeouts per half, they’re a little too valuable to burn. An injury however, is an official’s timeout – these are unlimited – and there’s no cost to the injured team outside of the last two minutes of a half, except that the injured player must sit out for the next play.

So in the current NFL world where fake injuries don’t have a cost (apart from having the ‘injured’ defender miss a play) and can help defenses maintain an easier pace – you could see why an Eagles fan might look at an opposing defender’s injury with suspicion.

Could the Eagles opponents be faking injuries to slow them down? The idea is one that makes the rounds in Eagles bars, but one that’s hard to actually evaluate. So this is my attempt to try.

Others have analyzed NFL injuries via metrics like games lost (i.e., players who aren’t active on game day because they’re injured), but to my knowledge, this is the first attempt to use play-by-play data to look at in-game injuries for trends and whether teams might be faking against the Eagles or other high-tempo teams.

The analysis is a bit long, so below are some quick takeaways:

- The Eagles suffered (or inflicted depending on your point of view) the most defensive injuries against the in league in 2014, and are 2nd in the league when adjusted for a per-play basis
- Across the league, there is a significant positive correlation between running more offensive plays and a higher per-play rate of defensive injury
- Such a correlation could be attributed to fatigue, but this correlation does not hold for the three other possible game situations (own offense, own defense, offense against) – these show no strong relationship between running more plays and a higher per-play rate of injury
- Taken together, these last two points support my hypothesis that players fake injuries against higher tempo offenses

Data Collection and Methodology:

I gathered play-by-play data from all the regular season games this year, and identified all the in-game injuries noted in the descriptions. In case you haven’t read play-by-play before, each play has its own line and explanation, and any play that resulted in an injury timeout is noted. Below is an example:

2-10-DET 40 (14:05) (Shotgun) 10-E.Manning pass incomplete deep middle to 80-V.Cruz (27-G.Quin). DET-27-G.Quin was injured during the play.

If an injury was noted as a stoppage, it was recorded. In an ideal world, we’d eliminate injuries that are serious and clearly not fakes, but there’s no detail on the injuries in the game data, so we have to take the major with the minor.

The play-by-play injuries were then coded as to whether they occurred to the offense, defense, or on special teams (e.g., kick coverage). There were approximately 700 total observations, and while it’s possible that not all injuries were noted in the play-by-play data, this is the only comprehensive source for such information. Given that there are ~700 injury stoppages in our set, that works out to 2-3 injury timeouts per game, which sounds possible but could also be low. It’s possible that whoever officially creates the play-by-play gets lazy and misses some, my assumption here is that if any injuries are somehow missed, they aren’t biased towards one particular side of the ball.

After gathering the data, one additional adjustment is for play frequency. Simply put, the more snaps a player gets, the more likely they are to sustain an injury. Therefore, any team that runs more plays is more likely to see a higher absolute number of injuries. To account for this, I also looked up the total number of plays for each team’s offense and defense during the course of the year – to understand the rate of injury rather than the total number.


Let’s start with the absolutes. I found 692 injuries in the play by play data, 66 of which were special teams plays. I took these out, because they aren’t central to the question of are teams faking injuries to slow down offenses. Of the remaining injuries, I looked at whether they happened to an offensive player or a defensive player and which team they occurred against, below is the data from this season:

Not a shocker to see the Eagles at the very top of that list, and indeed they led the league in defensive injuries against this season.

However, as I already noted, this metric can be misleading. The Eagles offense runs more plays per game than any other team, so we would expect them to be near the top of this list. We need to adjust our data for the number of offensive plays – and we can examine the rate at which opposing defensive players get injured against the Eagles and whether they are still an outlier.

So as we see when we look at it on a rate basis (number of injuries/number of total offensive plays), the Eagles are still close to the top of the league, and roughly 50% above the league average. Houston is just above them, and while no one would consider their offense up-tempo, the fact that the Eagles are so high would be consistent with the theory that opposing teams might be faking injuries to slow them down.

Now, before we get any further down the faking rabbit hole, what if there’s a simpler explanation that doesn’t involve fake injuries? There’s another obvious possibility to explain why the Eagles are so high in defensive injuries against. What about the idea that as you run more plays, players get more physically exhausted, and therefore are naturally more susceptible to injury?

That seems possible, right? So let’s examine that idea a bit.

The first thing we can do is very simple, does injury frequency vary by quarter? If teams get physically tired during the course of the game and that leads to more fatigue and more injury, there should be more injuries as the game goes on:

Interesting. This sort of muddies our waters a bit.

In absolute terms, the number of injures rises dramatically as the game goes on. Injury stoppages in the fourth quarter occur at 2x the rate they do in the first quarter. Part of that can be explained by the fact that the clock stops more frequently in the fourth quarter than the others (and thus more plays), but that wouldn’t explain a 2x difference. I would want to check against the sheer number of plays run by quarter, but I don’t have that data without a bunch of more work.

Still – it looks like that thinking may be reasonable, injuries increase as the game goes on. But it’s also interesting to note that the increase is much more pronounced on the defensive side of the ball. We’ll come back to that later.

For the time being, let’s move on to looking for evidence of fake injuries.

As a general framework for this analysis, I’ve split the types of injury stoppages into four buckets:

1. While on defense, your own team suffers an injury (Own-Defense)
2. While on defense, your opponent suffers an injury (Opponent-Offense)
3. While on offense, your own team suffers an injury (Own-Offense)
4. While on offense, your opponent suffers an injury (Opponent-Defense)

We’ve been focused on bucket #4 thus far, and saw that on a per-play basis the Eagles are close to the top of the league in terms of defensive injuries against on a per-play basis. We also saw that overall injuries increase as the game goes on – but it seems much more prevalent on the defense, which is the side that would be interested in faking injuries.

So can we look a bit deeper to see if play frequency increases injury risk across each type of injury stoppage? The idea that running more plays increases the rate of injury should not be exclusive to offense or defense – although it appears that way at first glance – it’s hard for me to believe that defensive players are in any worse shape or take any harder hits than offensive players.

To take a look at the issue, I ran some basic correlations across each of those four injury types, looking at the number of plays run and the rate of injury. Just to clarify, I summarized the four below:

1. Your defense runs more plays and gets injured more often (this would be a bad defense)
2. Your defense runs more plays and your opponent gets injured more often
3. Your offense runs more plays and gets injured more often (this would be a good offense)
4. Your offense runs more plays and your opponent gets injured more often

Again, if the rate of injury increases with more plays, we should see relationships in each of these situations. So what do we see?

#1 – So earlier we saw defenses suffering more injuries as the game goes on…and yet, when we look at number of defensive plays per game and the rate of defensive injury, there really doesn’t seem to be any relationship. Teams with defenses that are on the field a lot don’t seem to get injured at a higher rate than those who execute fewer plays.

#2 – Our next picture shows a similar lack of correlation, this time between defensive plays per game and the rate of opponent offensive injury. This idea would be that if an opposing defense is really bad, your offense gets more plays, and might get hurt more frequently. But the data shows nothing that looks like a relationship

#3 – Now we’re on the offensive side of the ball, looking at whether an offense that runs a lot of plays suffers a higher rate of injury. There’s actually a relatively weak negative correlation between running lots of offensive plays and suffering offensive injuries. If you want to believe in things like Chip Kelly’s Sport Science program, you would expect a negative relationship as teams that employ high tempo offenses are more adequately prepared to stay healthy while running it. While a very slight relationship exists, it doesn’t look to be that large, if it even exists at all.

#4 – Hmmm…now it’s officially interesting. When we look at the rate of defensive injury against offensive plays per game, there is our most significant positive relationship. A correlation of 0.39 is significantly more than we’ve seen in the other three instances, and it’s also the only one where there is a clear incentive to fake injuries.

Taken alone, this relationship might be explained by the fatigue theory, but I think it’s tougher to make that argument when you don’t see anywhere close to the same relationship in all other situations. When a defense is bad and on the field a lot, they don’t get hurt more often, when an offense is good and runs lots of plays, they don’t get hurt more often, and when a defense is bad and their opponent runs a lot of plays, they don’t get hurt more often. The only ones who show a substantial increase in injury stoppages as plays increase are opposing defenses.

To me, that’s pretty freaking suspicious. Either opposing defenses are the only ones who suffer from fatigue-related injuries…or maybe some of the injuries aren’t injuries at all.

Now, this is far from 100% conclusive. It may be that defensive players naturally get more fatigued than offensive players due to their roles (i.e., offensive players can take more plays off because they know the play calls)…but I don’t really buy that. I think there’s at least a little bit of shenanigans.

It’s also an entirely different question as to how much this even matters. Any fake injury will happen on the margins, as you see the number of total injury stoppages remain relatively small (2-3 total per game). But for an Eagles team that narrowly missed the playoffs, the marginal differences matter.


So is there a way to address teams that fake injuries? There are certainly options, but some of them are just impractical. The NHL has a penalty for diving, but you really can’t ask the officials to diagnose injuries and try to penalize fakers. You could charge a team a timeout, which the NFL already does if an injury occurs in the last two minutes. That’s much easier than trying to penalize teams, but also provides incentive for coaches and players to hide injuries (also, what do you do in the case of a ‘Body Bag Game’?)

One idea I think might actually be workable, is to tweak the NFL’s current rule for injured players. As it stands today, an injured player who causes a stoppage has to miss at least one play. Well, if you want to eliminate fake injuries, you should raise the cost to those players for faking, and you can do that simply by making them sit out longer. What if, when a player is injured and causes an official stoppage, they must sit out not for just one play, but for the remainder of that series or until a change of possession?

Missing the rest of a series is a bit more significant than missing just one play, and is something that could balance the equation on faking injuries. It also dovetails nicely with the NFL’s stated emphasis on player safety (interpret my use of the term ‘stated’ as you will, based on your own level of cynicism)

If there are fake injuries happening, such an increase in missed time might be enough to keep anyone from acting hurt. Requiring a player to miss the remainder of a series also isn’t as significant as forcing them out for the rest of a quarter or a game.

Some would argue that this isn’t even a problem worth focusing on. But if fast-paced offenses gain greater acceptance in the NFL (which will happen if more of them succeed), the issue will only become more prominent (beyond the realm of the paranoid Eagles fan) and could materially impact the game.

Summary Data

Below is a table of all the raw data I used here, as a reference:

Bonus – Jevon Kearse All-Stars

One last thing I did with this data, after pulling it together, was dig through and sum up all the specific players who sustained injuries in a game this season.

I wanted to look into it because I was really interested in what I’ve termed the ‘Jevon Kearse All-Stars.’ It may just be a bad memory on my part, but one of the things I really remember about Jevon Kearse’s tenure with the Eagles was his tendency to hurt himself and fall to the ground like he got shot. I feel like his injuries always looked more serious than they actually were. It’s possible I’m misremembering, and if so I apologize to the Freak. But with that said, here were the league leaders in injury stoppages in the NFL this year:

Now I’m not accusing these guys of faking injuries, these just happened to be the guys with the most injury stoppages in the play-by-play data (excluding special teams, which most of these guys don’t play anyway).

Enjoy your spot on the Kearse All-Stars guys – the trophy (it’s an ace bandage) is in the mail!

Saturday, January 10, 2015

NFL Hiring Season

As you guys know - I'm a big fan of the NFL off-season coaching carousel. How many people develop their own predictive model to see when coaches are going to get fired (brag break: and then have it picked up and advanced by the guys at Harvard)?

I really like it because it brings together two of my favorite things, football and hiring processes.

I've always been huge into recruiting for any organization I've been a part of - undergrad, my first jobs, business school, and then as a consultant - I'm always very into the process because a) I think it's very important and b) its also very fun.

Now, the Eagles got themselves into a ton of drama over competition for the player personnel decisions, and as that relates to recruiting, it got me interested.

Both Howie Roseman and Chip Kelly want control over player personnel decisions -- no doubt, those guys are both passionate about recruiting just like I am.

And for lots of other NFL teams, like the Bears for one, they're looking for new General Managers who will also be in charge of evaluating and retaining players.

It's all a ton of drama - but in the end - whomever you hire to run your team's personnel decisions - they'll still be wrong at least half the time and will likely get fired after 5-10 years.

It's a universal truth in the NFL - teams mis-evaluate players all the time...for the draft, for free agency, for anything, teams are going to be wrong a whole lot!

It seems like the best anyone can do is hit a little more than half the time. But what's interesting to me is that if any organization/industry is well suited to successfully recruiting, it's the NFL, and they're consistently terrible!

All the players considered for the draft have hours and hours of game tape - showing exactly how well they play. They get poked and prodded and measured in very official ways at the combine. They get interviewed. They have piles of statistics and detailed metrics showing their exact level of performance.

And yet so many of the picks are wrong.

Now that's not a problem I'm suggesting I have a solution to. But it's interesting to think about that relative to all the other recruiting the rest of us do in our organizations. Any recruiting you've done. You have 99% less information than the NFL. You have a resume, you have a couple conversations, maybe you have some references. But that's it. No one watches game tape of their potential new analyst (but wow would it be boring).

So if the NFL has such a huge level of detailed information on their recruits, and they screw up like 50% of the time. How often must the rest of us be screwing up in making hiring decisions?

Thursday, January 8, 2015

Free Stuff from Amazon

Because we're new parents and because I hate going to shop anywhere, we've been living our lives one shipment at a time.

I'd say it's worked out pretty well (except the one shipment of diapers that somehow never made it to our building) - but I have to say one recent experience left me a little confused.

We'd recently had our baby girl, right before the start of Hanukkah (otherwise known as Jewish-Christmas). And because you don't want your newborn daughter to forget her first Hanukkah - you have to make sure to buy her eight presents. You might argue that as a newborn, a baby is unlikely to be consciously aware of any gift you get them in their first month on Earth. And if you were to argue that, you'd be like me, and apparently, you would be 100% wrong.

So we ordered eight gifts - all of them small - and most of them on Amazon - for our girl's first Hanukkah.

And they arrived pretty quickly thanks to Amazon Prime.

But the weird part was with one of our gifts, a set of baby slippers that look like little Hippos.

We decided that we wanted to return said Hippos to Amazon. Fine. No big deal, I was told to file it as a return on the website and print out the requisite shipping label to return the goods, we'd get a credit on our account.

Sounded easy.

So I went to the computer and found the order in question, we still had the small box, so returning it wouldn't be a problem.

But after I checked the box to return the item, that's when things got weird.

Amazon basically said, 'Here's your money back, don't worry about the Hippos, we don't want them back'

The web site said our credit was processed, and it also said not to worry about returning the item.


For a dominating e-commerce company to basically give money away, seemed a bit strange. Jeff Bezos didn't become a billionaire by giving away stuff for free (he became a billionaire by selling stuff for slightly above free and investing all the profits in getting bigger)

I was so confused, I took a picture of the screen to make sure people would believe me.

Now - this could make economic sense. It's quite possible that for a $7.99 item, it's not worth it for Amazon to pay for shipping back to their fulfillment center and then for restocking it (in fact that's likely the case)

But now we have these Hippo booties...and we didn't pay for them...and we don't even really like them...but they're I guess we win?