Monday, June 16, 2008

In defense of the league

Photo by Flickr user Robbie-73 used under a Creative Commons license.

Via TrueHoop, a couple days ago, came this link offering up some basic analysis saying that the NBA favored large-market teams in the playoffs.

At first glance, I already had some preliminary doubts about the "study." First of all, he disregards the fact that the Grizzlies, Nuggets, Warriors, Wizards, Clippers or New Orleans Hornets ever made the playoffs. Secondly, the premise of the study assumes that teams are equally as good in the playoffs as the regular season, when clearly, whether via trades or effort given, some teams are obviously better.

However, I decided to give it the benefit of the doubt and run his numbers against some other statistics that I picked up around the internet. Now, I'm not a stat geek by any means, but I am an actuary by trade, so I do know my way around statistical analysis.

First, I plotted "Unexplained Playoff Advantage" against Urban Population. This showed significant positive correlation, but mainly just because New York and Los Angeles had such large populations. When those two data points were removed, there was almost no positive correlation at all.
Verdict: Possible

Next, I plotted UPA against average road attendance rate for the last 6 years. I decided to do this because I thought it might show out-of-market appeal among basketball fans for certain teams. Naturally, some teams perennially exhibited much higher road attendance rates than others, with Detroit being far and away the leader. However, there was almost no correlation at all between these rates and UPA.
Verdict: Probably not

Next, I plotted UPA against the number of times the team was on national TV last year (I would have liked to do a bigger sample, but I couldn't find the data). Luckily, I made a post about this early on in the season, which serves as an easy reference for my to grab some data. After this, I noticed that Phoenix was a team that had great road attendance and was among the top in national TV appearances, but had an atrocious -1.8 Unexplained Playoff Advantage. Disprover or outlier? Cleveland, behind Lebron James, also are among the best in road attendance and TV appearances, but dead last in UPA. Hmmmmm... Overall correlation: Zero to slightly negative.
Verdict: No chance

To conclude, I was skeptical that simply having a larger urban population meant that there would be higher ratings. Firstly, playoff basketball games will sell out whether they're played in New York or Atlanta, so that point is moot. Secondly, urban population does not necessarily equal high ratings, as the L.A. Rams will tell you. The real factor is the nationwide appeal of the team, which in my opinion at least, is measured more aptly by average road attendance rates and national TV appearances. I tried to also find stats on some other things such as average ticket prices and viewage by region, but I didn't know how to find such data. if anyone wants to direct me towards such stats, or give me a list of national TV appearances in the last 8 years or so, feel free to do so though. Also, if any one wants to see the raw data, feel free to e-mail me.

One cavaet when looking at my findings, or any for that matter. As I was compiling this, I was talking to Stro, the estranged Weekend Editor of this blog. I basically told him that if my findings contradicted the previously concluded ones, I would post them, but that if I confirmed those results, I wouldn't take any action. Basically, what I'm saying is that, as a basketball fan, it is very hard for me to admit even the possibility of the league being rigged. I imagine that for someone who is convinced that the league is fixed, it would be very are to convince them otherwise as well. Because of this, there is going to be significant confirmation bias in any data we present, so obviously, don't take one source as the be-all-end-all of discussions. This is of course, obvious to most people, but I know that some people are very influenced by fancy stats and graphs, so I wanted to throw that out there.