Some Nice Things I’ve Missed – NBA Playoff Edition

Posted on May 22, 2007 by

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This column is over 2,000 words. So let me apologize up front for wasting your time today with way too many words. If you do manage to get to the end of this post, you will see the following:

– a list of the NBA’s Best Teams in 2006-07

– a discussion of my efforts to predict the playoffs for True Hoops

– a review – built upon the work of Stephen Dubner – of The Black Swan by Nassim Nocholas Taleb.

– an possible explanation for why Chicago failed to defeat Detroit in the playoffs

– a link to my latest column for The New York Times

– and a quick poll

Again sorry for the length, but I got a bit carried away last night.

The NBA’s Best and Predicting the Playoffs

Continuing yesterday’s Sinatra inspired theme, I continue looking at “some nice things I’ve missed” by turning my attention to the NBA playoffs.

As I joked last month, the Iverson forecast was the first time an economist ever had a prediction come true (not a very funny joke, but a joke nonetheless). Henry Abbott of True Hoop has decided to put my power to predict to a test. Specifically, Abbott has asked a collection of “stat geeks” to forecast the playoffs in the NBA.

Before I get to the problems with this test, let me reveal my “brilliant” strategy. The following table reveals all the data I considered.

Table One: The NBA’s Best Teams in 2006-07

Yes, all I considered was each team’s efficiency differential. And the further apart the teams, the shorter I expected the series to be. Consequently, I took Chicago over Miami (more on this series in a bit). I also took Chicago over Detroit and Dallas over Golden State. The problem with this strategy is that it ignored the fact New Jersey had a healthier Richard Jefferson to combat the Toronto Raptors. In other words, the health of the players at the time the playoffs started was not considered. Given my time constraint, though, my simple strategy was the best I could do.

So far my strategy has not done too badly. Heading into the conference finals I am three points off the lead. Unfortunately, it seems very unlikely that I will win the coveted blazer Henry Abbott is bestowing on the winner.

The two leaders are Jason Kubatko of Basketball-Reference.com and Kevin Pelton. Everyone picked the Spurs and Pistons to win in the conference finals. Pelton and I do differ, though, on how long we guessed the series would last. So if the Spurs win in five and the Pistons win in seven, I will pass Pelton. Kubatko, though, will still be three points ahead because we picked each series to last the same number of games. My only hope is to differ from Kubatko in picking the Finals. And I think, as I will explain in a moment, that this would require that I pick against my “brilliant” strategy.

Why do I have to pick against my strategy? The closeness in the standings reveals one of the difficulties with this contest. It turns out that the “stat geeks” tend to see teams the same way. In other words, we tend to agree that teams are best evaluated in terms of offensive and defensive efficiency. Consequently five out of six of the contestants picked Chicago over Miami. Four out of six took Chicago over Detroit. And as noted, all of us picked Detroit over Cleveland and the Spurs to defeat the Jazz. My sense is that Kubatko and I will reach the same conclusion about who should win in the Finals. So I will have to pick the statistical “underdog” if I am going to win this contest.

Beyond the issue of the stats people seeing teams the same way, this contest also has one other problem. Basically the playoffs suffer from the classic “small sample” problem. As the Dallas Mavericks discovered, the best team does not win every game and it’s possible for an inferior squad to win a best-of-seven series. Statistical analysis doesn’t work very well with small samples, so predicting the playoffs is not a very good test of what we do.

All that being said, it doesn’t mean the contest isn’t a great deal of fun. It certainly has given me a rooting interest in every series, which makes the playoffs that much more enjoyable.

The Black Swan

The small sample nature of the playoffs doesn’t prevent people from trying to “explain” what we observe. For example, much has been written about various moves the Mavericks should make after the Warriors eliminated the team with the best regular season record (although not the best efficiency differential) in the first round. Or what the Bulls or Suns should do to get past the second round of the playoffs. Such explanations remind me very much of the arguments advanced by Nassim Nocholas Taleb.

One of the perks of writing a book is that publishers now send me advanced copies of other people’s books to review. Consequently, I was given an advanced copy of The Black Swan, Taleb’s latest book published by Random House. Taleb’s first book was entitled “Fooled by Randomness.” This first book, which was excellent, detailed the problem people have forecasting on the stock market. The Black Swan is basically a sequel to Fooled by Randomness. Although I could offer a detailed review, Stephen Dubner – of Freakonomics fame – saved me the trouble by writing a review that captured my basic sentiments.

… you will probably enjoy the writing of Nassim Nicholas Taleb, a polymathic gentleman whose new book is called The Black Swan: The Impact of the Highly Improbable. Here’s how its dust jacket succinctly describes the thesis: “A black swan is a highly improbable event with three principal characteristics: It is unpredictable; it carries a massive impact; and, after the fact, we concoct an explanation that makes it appear less random, and more predictable, than it was. The astonishing success of Google was a black swan; so was 9/11.”

I am about a third of the way through The Black Swan, and am finding it to be one of the most fun and challenging books I’ve read in a long time. It barrels its way through history, psychology, philosophy, statistics, etc. You find yourself arguing Taleb every third sentence or so — but, to me, that is part of the great fun. He is a brash, stubborn, entertaining, opinionated, curious, cajoling writer and thinker. I also very much liked his previous book, Fooled by Randomness: The Hidden Role of Chance in Life and in the Markets. The two books have similar worldviews but it is worth reading both of them. (FWIW, based on what he’s written, I think he would probably hate Freakonomics, and he explicitly hates the financial end of economics.)

I’m sure that some of you have already read The Black Swan, since it is a New York Times best-seller. If not, you can learn quite a bit about Taleb from his home page, as well as from this very good profile that Malcolm Gladwell wrote a few years back.

Like Dubner, I am a third of the way through the Black Swan. I also had the same impression. This book is a poke in the eye to those who think the analysis of stats provides the answer to everything. And this book forces us to ask if our explanations of the past are simply “concoctions” that allows us to believe the future can be predicted with great accuracy.

Defying the Black Swan

Although I agree with Taleb that we tend to “concoct” explanations of the past, this doesn’t stop me from “concocting” here and there. For example, when we look at offensive and defensive efficiency we see that Chicago was a “better” team than Detroit this year. Yet the Pistons defeated the Bulls in six games. How can this be explained? Well, let me “concoct” an explanation.

In the first round the Bulls faced the Miami Heat. Chicago probably thought they were facing the defending champs. Unfortunately, Miami had a big incentive problem. As I noted two weeks ago, players do not get paid much for the playoffs. So the only purpose in playing is to win the games. But the Heat just won last year, and since championships won (like most everything else) are characterized by diminishing returns (the first one makes you happier than the second), the Heat were not as driven to win in 2006-07. Plus many of their players are old and/or hurt, and they knew given their status that winning this year was a long-shot. Given all that, the Heat may not have been trying that hard in the first round.

But the Bulls probably thought the Heat were giving it their best shot. And when the Bulls won so easily they might have thought the playoffs were going to be easy. Then the Bulls faced the Pistons. The Pistons are not old and hurt. They also have something to prove (can they win without Big Ben?). And in the first two games the Pistons showed the young Bulls how hard a team can play in the playoffs. By the time the Bulls got the message, Chicago was in too big a hole to recover.

All that being said, what I just said is probably just nonsense. Again, there is the whole Black Swan issue. People look at the outcomes in the playoffs and then jump to conclusions. For example, people have argued that San Antonio defeating Phoenix is “proof” (a word that should be removed from every sports writer’s vocabulary. There is very little that is “proved” in sports) that how Phoenix plays in the regular season can’t work in the playoffs. When we look at each team’s efficiency differential, though, we see that the Spurs were the better team in the regular season and thus should have been favored.

That doesn’t mean, as the Warriors demonstrated, that the Spurs were guaranteed a victory over the Suns. The efficiency story, though, does tell us that the Suns should have expected their season to end in mid-May.

Although upsets can happen, your best bet in the playoffs is to be the better team. So going forward the Suns simply have to keep trying to build the best team possible (and getting rid of Shawn Marion is not likely to be a step that is consistent with the objective of building the “best” team possible).

Writing for The New York Times

Okay, I have said in a span of over 1,000 words: “Playoffs defy prediction” and the “Playoffs are predictable.” One of those views has to be right.

Two weeks ago I wrote another column for The New York Times entitled “The Short Supply of Competitive Balance” that you may have missed. And this column seemed consistent with the “playoffs are somewhat predictable” sentiment.

As this column notes, the NBA championship has only been won by a handful of teams in the past few decades. And if either the Spurs or Pistons win again, the title will once again reside in a familiar place. In this column I utilize “The Short Supply of Tall People” argument detailed in The Wages of Wins to explain why the NBA lacks competitive balance. For those who do not have insider access to The New York Times, you can see the same argument in The Wages of Wins or in the following posts:

The Short Supply of Tall People

On Jordan and Rodman, Again

The Changing Fortunes of Jamal Magloire and Zach Randolph

Why Have a Draft?

Quick Poll

Okay, now that I am back there are a number of topics to write about. What would you like to me write about first? Here is a list of potential topics:

Who is the MVP in the NBA (if Wins Produced is your criteria)?

Who is the NBA’s best sixth man?

Who was most improved in the NBA in 2006-07?

How does experience in the NBA impact player performance?

Let me know in the comments which of these four topics you want to hear about first. My plan is to get to these four topics in the next week or so. By then we should be closing in on the Finals. During the Finals I will repeat what I did last year. Specifically I will demonstrate again that I really don’t get the Black Swan argument by offering analysis of each and every game. Hopefully this analysis will be chocked full of “concoctions.”

– DJ