Category: Sports

Why is there so much falling in top-level figure skating?

Chris Hartman poses this question.  He favors higher penalties for errors and thus safer routines.  I would think that the optimum (in a lot of other sports, too) has shifted in the other direction.  In the old days, everyone watched on TV and suffered through a lot of error-ridden performances.  The average quality of performance mattered more.  These days the very best performances are reproduced on YouTube and other venues.  That indicates we should seek a higher variance of performance quality, since we can keep and reproduce the very best for most of the relevant viewers.

What sports rule changes does this imply?

Less is more?

I found this, from Ric Bucher, on ESPN:

…the harsh reality, says one GM, is that winning a championship this year is not a priority over keeping free-agent-to-be LeBron James. In fact, there's a concern that if James wins a title this year for the Cavs, it might be easier for him to go elsewhere. The best scenario, then, if the Cavs want to make it hardest for LeBron to leave, is give him everything he wants and have their title chase falls short. And if you question valuing LeBron over a title, forget it. James roughly doubles the value of the Cavs' franchise, according to league sources. It might offend winning-is-everything sensibilities, but the truth is $200 million (the value James adds to the Cavs) means more."

What is the implicit model?  Is it a behavioral claim about James, namely that he dislikes frustration and wants to finish the job in Cleveland?  Or is it about the bidding behavior of other teams, namely they want him most (and there are more dimensions to a deal than just salary-capped $$) if he wins a title and less if they think he will quit on them too?

Civil war exposure and violence

That's a new paper by Edward Miguel, Sebastian Saiegh, and Shanker Satyanath and here is the abstract:

In recent years scholars have begun to focus on the consequences of individuals’ exposure to civil war, including its severe health and psychological consequences. Our innovation is to move beyond the survey methodology that is widespread in this literature to analyze the actual behavior of individuals with varying degrees of exposure to civil war in a common institutional setting. We exploit the presence of thousands of international soccer (football) players with different exposures to civil conflict in the European professional leagues, and find a strong relationship between the extent of civil conflict in a player’s home country and his propensity to behave violently on the soccer field, as measured by yellow and red cards. This link is robust to region fixed effects, country characteristics (e.g., rule of law, per capita income), player characteristics (e.g., age, field position, quality), outliers, and team fixed effects. Reinforcing our claim that we isolate the effect of civil war exposure rather than simple rule-breaking or something else entirely, there is no meaningful correlation between our measure of exposure to civil war and soccer performance measures not closely related to violent conduct. The result is also robust to controlling for civil wars before a player’s birth, suggesting that it is not driven by factors from the distant historical past.

One question is whether such behavior occurs because the player's psyche has somehow been brutalized or whether it is a deliberate affect aimed at a violence-expecting audience back home.  It's related to which variables might best predict the propensity of an NBA player to pick up technical fouls; would that be correlated with urban upbringing, the nature of the audience (home vs. away, TV vs. live crowd, etc.) or perhaps correlated with early brushes with the law?

If you wish to skim the results, start with p.25.  The Colombian players pick up a lot of yellow cards.

Root for the home team

Controlling for location and time fixed effects, weather factors, the pre-game point spread, and the size of the local viewing audience, we find that upset losses by the home team (losses in games that the home team was predicted to win by more than 3 points) lead to an 8 percent increase in police reports of at-home male-on-female intimate partner violence.

Here is the source paper and that is from David Card and Gordon Dahl.  In contrast, if you go see a violent movie, for that same length of time you are sequestered and thus less likely to be a danger to others.

How to improve basketball

Tim Miano writes to me:

I am a longtime MR reader. I have a hypothesis about how basketball could be much more exciting, and I can't for the life of me figure out why people who are into sports haven't widely considered it (as least as far as I know).

Here is my simple thought: games should be played as best 4 out of 7 periods — perhaps 7 minutes each or perhaps slightly varied period lengths, 6 – 8 minutes long. Maybe the number or usage of timeouts or foul-outs would need to be fiddled with. Maybe playoffs would be slightly different. But that's pretty much it. The best part of a basketball game is almost always the last few minutes, and it seems like the incentives for exciting play would persist more throughly under this design. Teams would need more endurance and deeper benches, but that seems like a good thing. Other than obsoleting old records and the tradition of the game, I can't think of any downside. Maybe marginal cost v. marginal benefit, à la owners/players wouldn't extract much more money from fans but would have to work harder? Maybe the length of games would vary too much for broadcasters to be happy? But still, a *much* more exciting game.

My Hansonian observation is that fans seem to prefer basketball seasons with a dominant player (Jordan) or perhaps a dominant match-up (the old Lakers vs. Celtics rivalries).  For the season as a whole, we don't seem to want too much suspense.  Does suspense distract us?  Are we really more interested in multi-tasking?  Or does suspense make it harder to affiliate with the idea of truly skilled and noble players?  If we are suspicious about having too much "suspense" across the course of the season (call it parity, if you wish), might we be suspicious about having too much suspense in the course of a single game?

What's so great about suspense anyway?

Here is Jeff Ely on related issues.


The subtitle is How Gamblers, Managers, and Sports Enthusiasts Use Mathematics in Baseball, Basketball, and Football and the author is Wayne L. Winston.

I read only the sections on the NBA.  He proposes a four-factor model to evaluate teams: Effective Field Goal Percentage, Turnovers per Possession, Offensive Rebounding Percentage, and Free Throw Rate, or how often a team gets to the line.  He claims you can raise your PER by taking lots of bad shots and for that reason PER isn't a great measure.  Kevin Garnett was an underrated player.  Playing four games in five nights hurts you by an average of four points.  The raw data, unadjusted for the Lucas Critique, indicate that when you are up by three points, and there are less than seven seconds left, you should not foul the other team.

Some people will enjoy this book.  Baseball receives the most attention.  Each chapter simply ends and the author moves on to another topic without any overarching narrative other than the statistical method itself.

Here is some of his blogging.

NFL player bankruptcy

The ever-excellent Mark Steckbeck offers up a quotation from Yahoo:

78 percent number (i.e., 78% of NFL players go bankrupt within two
years of retirement) is buoyed by the fact that the average NFL career
lasts just three years. So, figure a player gets drafted in 2009, signs
for the minimum and lasts three years in the league: He will have
earned about $1.2 million in salary. Factor in taxes, cost of living
and the misguided belief that there will be more years and bigger
paydays down the road, and it becomes a lot easier to see how so many
players struggle with money after their careers end.

What happens when there are no more world records left?

Hello Tyler

I'm a British blogger and avid reader of your superb blog. I have a question for you and your readers.

In the wake of the World Athletic Championships (and Bolt's spectacular achievement) I've been wondering: what will happen when the last world records are set?

For example: nobody will ever run the 800m in one second.

Which means someone, somewhere will set a record in that event that never gets broken.

Similarly, nobody will ever throw a javelin five miles. There's got to be a limit point.

What happens after that? What happens when all the Final Records, as it were, have been set?

Of course, we won't know it when it happens. We'll keep striving to break them. But at some point we'll look back on the preceding twenty years and remark on the fact that no new records have been set. In the meantime, incrementally, everyone has caught up to a similar level as everyone else.

What happens then? Does track and field die?

Of course a new record may beat an old record in asymptotic fashion, but at some point this ceases to be exciting.  One partial solution is to redefine the unit of achievement: how many 100-meter races in a row did the person win against peers?  There can be a "Grand Prix" of accumulated race performances.  Another partial solution is to introduce weights or enhancements, to redefine the terms of the competition.  In short, I expect entrepreneurs will always find ways around this problem.  In chess the gaps between the top fifteen players have narrowed considerably, yet the public doesn't seem to have lost interest in the game.  Alternatively, individual basketball scoring performances still interest the fans, even though Wilt Chamberlain's 100-point game probably will never be topped.  It's enough if the activity itself is fun.  What else will happen?

Insurance markets in everything

…two Long Island insurance brokers have developed a way for the
fantasy owner to experience the bittersweet taste of an insurance
payout when their superstar goes down with a season-ending injury.

That's right. Pro teams have hedged against their largest contracts
with insurance for years. Now owners of fake teams can now protect
themselves against the injuries of real players with actual insurance

I thank Jon for the pointer.  I wonder if this isn't a publicity-generating loss leader for their other insurance policies.

The price of anarchy in basketball

Brian Skinner writes:

Optimizing the performance of a basketball offense may be viewed as a network problem, wherein each play represents a "pathway" through which the ball and players may move from origin (the in-bounds pass) to goal (the basket). Effective field goal percentages from the resulting shot attempts can be used to characterize the efficiency of each pathway. Inspired by recent discussions of the "price of anarchy" in traffic networks, this paper makes a formal analogy between a basketball offense and a simplified traffic network. The analysis suggests that there may be a significant difference between taking the highest-percentage shot each time down the court and playing the most efficient possible game.

Here is some additional explanation.  I thank Michelle Dawson for the pointer.

The evolution of sports rules

Gibbous, a loyal guy, asks:

The evolution of the rules of sports as a standards-setting process – – are the rules of basketball (or baseball, golf, football…) optimal in the same way that (arguably, at least) the QWERTY keyboard is?

I would put QWERTY aside, as that is a non-proprietary standard.  With a proprietary standard, I see a few reasons why the evolution of sports rules may be less than ideal. 

1. The rules may be geared toward the sale of merchandise, which implies an appeal to the young and to the least common denominator.  This is mostly an aesthetic objection, although you can tell a story about the purist being a neglected infra-marginal consumer.

2. The rules of the sport may be geared toward television advertising revenue, with the above argument repeated.

3. The league has market power and at some margin it will produce too few franchises; think of the league as selling franchise rights for money.  Some of this output restriction is quality control but some of it sheer monopolization.  (Allowing more franchises, at some margin, will loosen the meaning of the rules and conventions.  Imagine if way back when they had let NBA teams play the Harlem Globetrotters every now and then.  In what year would the fifth-best NBA team start beating them?)

4. If the league restricts the number of teams, other distortions will result, such as when the city of Memphis overbids for the right to have an NBA team.  Furthermore franchises will end up too far apart in geographic terms; bids are determined by producer surplus but societal welfare depends on consumer surplus too.

5. Sports leagues lead to less than optimal levels of player mobility; think monopsony power and the desire to redistribute rents to team owners.  Remember Curt Flood?

6. It is a good industrial organization question whether sports leagues will produce too many or too few games in a season, relative to a social optimum.  Figure it out!  I have an answer in mind but I'm not letting on about it.

Excess leverage was almost everywhere

And the job market is hurting in many sectors:

On opening night, there could be 30 or 40 fewer NBA jobs than a year ago.

Depending on exactly how large a roster each team wants, the total number of players is a bit higher than 400, so in percentage terms this is a big drop.  You'll notice that while NBA wages are adjusting downwards, the quantity of labor demanded is falling as well.

A simple economic model of today’s NBA

Given economic bad times, many teams have overspent.  But they have lots of long-term contracts, plus there is a salary cap and luxury tax for going above that cap.  Real wages ought to fall but most of them cannot fall right away.  If a player becomes a free agent, few teams will bid and those players will absorb a disproportionate share of the required wage cuts (the pricing of complementary inputs had some indeterminacy anyway, plus there is an AC constraint). 

The lower returns available mean that a given free agent is more likely to be a self-deluding trouble maker who has worn out his welcome (Artest, Gordon, etc.).  This favors teams with dominant players (Cleveland), strong systems (Boston), and strong coaches.  All those teams can swallow the troublemakers without cracking up.  It also favors teams which suffer from well-defined "missing pieces."  It favors already-good teams and indeed we see that Cleveland, Orlando, San Antonio, and LA have been major players in the free agent or trade markets.

I predict a greater dispersion of win totals for next year's season.

I am wondering to what extent a similar analysis applies to economics departments, or to teams of bloggers, or to other groups of complementary labor inputs.

Addendum: TrueHoop comments.