Do offensive, defensive, or well-rounded teams fare best in the playoffs?
We’ll see if there’s a correlation
The Relationship Between Goals For, Goals Against, Goal Differential and Playoff Success
The Study: While making predictions in the past about NHL standings and who would win the Stanley Cup, we wondered: Do higher scoring teams fare better in the Playoffs? Are teams with better defense stronger? Or is it the right combination that matters most?
In this study, we took a look at team Regular Season Goals For per Game Played (GF/GP), Goals Against per Game Played (GA/GP), and Goal Differential per Game Played (Diff/GP) in relation to Playoff Points from 2013-14 to 2019-20 to see: 1. if there was any correlation between these stats; and 2. if any stat had a noticeably higher correlation.
In relation to Playoff Points:
GF/GP had a correlation of 0.36;
GA/GP had a correlation of -0.41; and
Diff/GP had a correlation of 0.53.
Discussion: While Regular Season performance doesn’t necessarily predict Playoff performance, logically, Diff/GP obviously should have the strongest correlation and be noticeably different from the others. After all, having a greater difference between GF and GA should mean that you’re a stronger team and thus are likely to go furthest in the Playoffs.
That being said, one could have predicted that maybe an offensive powerhouse could simply outscore their competition, disregarding defense almost entirely. Conversely, one could have predicted that maybe the best defensive teams could stymie offensive teams’ production, make things a game of inches, and win in the end. Combined, I didn’t think it was necessarily obvious that Regular Season Diff/GP would have the strongest correlation to Playoff success and therefore this study was definitely worth pursuing.
But now that we know Regular Season Diff/GP has the strongest correlation with Playoff Points, what else can we gather from the results? Well, it also seems likely that defensive performance is a better predictor of Playoff success than offense. Thus, if you were to bet on teams, you might more heavily favor ones with the best defensive systems, Coaches, and/or Goaltender in the Playoffs. For example, the 2013-14 Stanley Cup Winning Los Angeles Kings had the lowest GA/GP of the 214 teams examined and the 2014-15 Chicago Blackhawks were 5th.
Nonetheless, since correlation doesn’t equal causation, this data only serves as supplemental information. After all, the 2017-18 Cup winning Washington Capitals were 80th in Diff/GP, the 2016-17 Pittsburgh Penguins were 110th in GA/GP, and the 2018-19 Tampa Bay Lightning flopped with 0 Playoff Points despite being #1 of 214 teams in Diff/GP.