COLLEGE PARK, Maryland – Whether you are a fan of the NBA or a network executive looking to attract as many viewers to TV screens as possible, your hopes for the postseason are the same: an exciting outcome.
Of course, the word “exciting” is subjective. To some, an exciting postseason would lead to a rematch between the Golden State Warriors and the Cleveland Cavaliers for the third straight year — and LeBron James’ seventh consecutive finals appearance. To others, an exciting postseason would be filled with upsets galore.
In order to create a consistent definition, Mike Beuoy, creator of the sports data visualization blog inpredictable.com, quantified the term by creating “the excitement index.”
The number is derived from win probability graphs, an example of one from Beuoy’s site is shown below.
The line is a live probability tracker, which measures each team’s chance of winning over the span of a game, accounting for the score and remaining time. The excitement index measures the total distance the line travels as it moves up and down throughout the game.
We used the excitement index to attempt to predict which first-round playoff matches would offer the most back-and-forth play. We started with the Cleveland and Indiana Pacers first-round matchup, examining the average excitement index from the four times those teams played during the regular season. We used the same method the rest of the teams.
The most exciting matchup — Cleveland-Indiana — was a continuation of the LeBron James vs. Paul George rivalry that hasn’t seen the postseason since 2014. In the conventional sense of excitement, there aren’t many surprises here.
Houston Rockets – Oklahoma City Thunder was a battle between the two leading MVP candidates. While it was fun to watch Steph Curry cook his way through Portland’s defense, it did not yield a fun back-and-forth battle between the teams.
It’s commonly believed that once the playoffs start, the regular season no longer matters. If you want proof, look at how many Presidents’ Trophies (for best regular season record) the Washington Capitals have (3), and compare that to their number of Stanley Cups (0).
Our playoff excitement prediction did not hold up too well to reality. The graphic below compares our first-round series prediction (based on the regular season) with the actual average excitement index (based on the postseason so far).
Four of the eight first-round series averaged higher excitement indexes than they did in the regular season and some series even experienced some significant index jumps (see L.A. Clippers-Utah Jazz series). These numbers become more impactful when compared to last year’s postseason.
In 2016, the first-round excitement predictions were similar to this season’s. Though the range of the indexes may be smaller, the averages of each year’s first-round matchups come out to roughly the same, about 6.08.
The similarities stopped there. Overall, viewers of the NBA playoffs saw a first round that was less exciting than the regular season.
Of the eight first-round matchups, only two — Cleveland-Detroit Pistons and San Antonio Spurs -Memphis Grizzlies — averaged slightly higher indexes in the playoffs than in the regular season. As a whole, the excitement average dropped from 6.089 in the regular season to 5.364 in the playoffs.
The lazy argument: this makes sense because fans already know who is going to make the finals and the players let those storylines get to them and affect their play. Thankfully, this year’s playoffs dispel that point.
This season, the playoff excitement index was higher than the regular season excitement index. Yes, it was only a .053 increase (from 6.075 to 6.128), but it’s a .86 increase from the year before. Only one series, Golden State-Portland, had a lower average index than last season’s playoff average. Five series fell into that category in 2016.
It’s difficult to point to one explanation. It could be that teams in both conferences got better, particularly in the East where wins were distributed more evenly. Whatever the case, one thing is certain: the playoffs these year are definitely worth the watch.