My father was a big fan of the Chicago Bulls back in the ’80s and ’90s, so I had the good fortune of watching some of the best playoff basketball (i.e. Michael Jordan) that the NBA (and the world) has ever witnessed. Perhaps that is the same reason why the last decade or so of NBA basketball has seemed to pale noticeably in terms of excitement. It is generally agreed upon among basketball fans that the game as it is played today is (a lot) less physical (and perhaps less exciting) than it once was.

Officiating has also seemingly become a bigger determinant of results, and like virtually all professional team sports, the blame often lands on the referees. “If it weren’t for that call, they would have won the game,” is a phrase we hear all too often, and one that I am guilty of committing as well. However, have changes in officiating really been that significant over the last few decades, and if so, how would we measure such a phenomenon? The answer, of course, lies in the numbers.

Luckily, statistics for the NBA are readily available, but for the purposes of my project, I decided to look at playoff statistics from the 1983-84 season to the latest 2012-13 season. However, even if the data is easily accessible, oftentimes the most time-consuming aspect of a project is collecting the data and organizing it in a way that makes it easy to analyze. This was no exception. Luckily, with a little vlookup and text parsing (the latter is needlessly complex in Excel) magic, I was able to largely automate the process of converting 30 years of raw playoff data into something I could process more easily.

My first goal was to see if there were any high level trends in the NBA playoffs through time, in particular the number of games played and the point differential in each game. Moreover, I wanted to analyze these metrics by playoff round (e.g. first round (1R), conference semifinals (2R), conference finals (3R), and finals (4R)). If we were to believe that officiating actually had a measurable impact on playoff results, we may expect to find the following:

• An overall longer playoff campaign
• Smaller average point differentials, to convey the appearance of “closer” games

Why would the NBA want any of these things to happen? The answer is simple: profits. More games played/closer games = more tickets sold/higher TV ratings. In fact, the NBA switched from a best-of-five format to a best-of-seven format in the first round starting in the 2003 playoffs.

The Results (and the data)

I’ll make a few observations, but the data really speaks for itself here. In the first chart, we see that after adjusting for the NBA’s change in playoff format since the 2002-03 campaign, both the average numbers of games played in the playoffs and the average number of games played per round has not shown any noticeable shift through time. The average points differential chart shows the same story, and in fact both charts seem to suggest some cyclical trends through time. Lastly, the average free throw attempts and fouls chart actually displays a noticeable decrease through time on a per game adjusted basis. Perhaps this is a testament to just how physical the game was back in the 1980s and 90s, which MJ himself has suggested on many an occasion.

Conclusion

The data doesn’t seem to indicate any obvious playoff trends that may have been caused by officiating. However, more granular foul data (which may not be available) may help clarify the story. In particular, even if the average number of fouls per game has trended down over the last 30 years, have the types of fouls called changed in any significant way? Perhaps more calls are coming during particularly tight stretches of games, or conversely, during blow outs, to ensure that the losing team is “still in it.” Of course, all of this is pure speculation, and without hard evidence, it is difficult to move forward. As Sir Arthur Conan Doyle once said through his most famous character Sherlock Holmes, “It is a capital mistake to theorize before one has data. Insensibly one begins to twist facts to suit theories, instead of theories to suit facts.” Until such facts are found, our theories will remain theories.