Most of us are by now familiar with the concept of win probability. The current state of the game has many implications on the way the game is played and I’ve been a proponent of using it to adjust statistics as an alternative to using just the score, since win probability itself is simply a function of score and time remaining.
In the spirit of the playoffs today I want to use win probability and corresponding statistic leverage to measure ‘excitement’. Leverage is the total win probability added (and for the opposing team, lost) on account of a particular goal. If a team scores a goal in the last second of the third period, the win probability added would be about 0.5: they went from essentially 0% to 50% chance of winning the game.
Adding up all these changes in win probability during the course of a game gives us a measure of how ‘exciting’ the game was:
The most exciting game according to this metric in the post-lockout era was game 2 of the 2010 first round match-up between Colorado and San Jose. The two teams traded goals 5 times (!) in a row, scoring one after another until Devin Setoguchi broke that streak, scoring five and a half minutes into overtime marking the first goal of the game not preceded by an opposition goal (Pavelski tied the game at 5-5 with 30 seconds to go in the third period). Two Stanley Cup Final games make the list, with Detroit and Pittsburgh’s 2008 game 6 at number 4 and Boston and Chicago’s 2013 game 4 at 6 on the list. Googling any of these games will get you plenty of articles that include the word ‘wild’, so I think we’re on the right track with this metric.
It may be hard to wrap one’s head around what a total win probability added means. From a team having no chance of winning the game to definitely winning the game is 1. These games emotional roller coaster ride were all more then twice as intense as tying the game and then winning or losing it in the last minute of regulation.
Summing these win probabilities added for an entire series gets us an aggregate measure of series excitement. The top 10 are listed above. The most exciting series in the post-lockout era belongs to the 2009 Eastern Conference Final. Five of the seven games were decided by one goal and three went to overtime. A lopsided game seven masks the intensity of the series, St. Louis Chicago from last year makes an appearance. Remember that one? St. Louis took the first 3 of 4 but Chicago stormed back to win game 5 and 6 but Troy Brouwer won it for the Blues in game 7 with a goal that aptly reflected the series: with the puck inches from goal, Brouwer hit the post on his first attempt, missed the puck on his second before finally burying it.
Finally we have each of the season’s playoffs ranked by total excitement. The post-lockout’s most exciting playoffs, 2014 was about 15% more exciting then the least, 2015.
What will this year’s edition of the NHL playoffs bring in terms of excitement? It’s impossible to say, and there hasn’t been any sort of trend on that front year to year, however, with what many this season have perceived as an increase in parity throughout the league, it’s possible that this could have some positive effect on total playoff excitement.