There's So Much More Hitting in the NHL Playoffs
April 15, 2015
You hear every year that playoff hockey is a whole different game from regular season hockey. If playoff hockey is so much more intense than regular season hockey, then we should probably be able to see evidence of in the play-by-play. I looked at hitting numbers for an article for FiveThirtyEight today. I found that the average playoff game has 15 more hits (36%) logged than the average regular season game.
I dug a little bit further and found that this difference is remarkably robust. When you only compare playoff games to regular season games between two eventual-playoff teams, the difference is 14. Still pretty substantial. The result also holds up if you only compare playoff hockey to games in the last few weeks of the regular season.
I had some concern that this might not be a result of changes in how the game is played, but rather in how the play-by-play are recorded. The main issue is that if the NHL added an extra person or two to the group recording the play-by-play during the playoffs, then this could drive up the number of “hit” events that get recorded. I spoke with executives at two different NHL teams and they both reassured me that the people collecting the play-by-play stay the same from regular season to the playoffs. Of course, it’s possible that some of the 36% increase is attributable to confirmation bias among the data collectors. They “know” that playoff hockey is more intense, so they’re subconsciously motivated to record extra hits. While this seems totally reasonable, a 36% jump is way too massive for it to be totally attributable to confirmation bias. Maybe a 3-5% jump, but not 36%.
Below is my original version of the graph that was included in the FiveThirtyEight article. This version actually shows the confidence intervals for each team’s difference of means between regular season hits and post season hits.