Introducing face-off percentage opponent hand splits, and revealing hidden biases

jacketswings

Have you ever wondered whether certain players win more of their face-offs when a left-handed (or right-handed) opponent lines up against them? It’s a request I’ve gotten numerous times here, so I’m happy to announce that player profiles on faceoffs.net now contain split stats against left/right handed opponents. You can also view this data across the league’s top face-off takers here.

To show what you can do with this information, here are two interesting charts that may be of particular interest to Anaheim Ducks and Nashville Predators fans:

getzlaf_web
ribeiro_web

Ryan Getzlaf, an approximately average overall face-off taker, has consistently shown an ability to win more of his face-offs against opponents who shoot right-handed — a bias that has persisted as his performance has slightly improved each of the past four years.

On the bottom, Mike Ribeiro‘s overall face-off numbers display his struggles, but one of the key reasons behind them may have gone unnoticed until now. Ribeiro goes from merely mediocre against left-handed shooters (who take about 63% of the NHL’s face-offs, but that’s a topic for another day) to downright awful against right-handed shooters, and this spread is consistent across all four years that are currently in my database.

Most players do not display such a wide disparity in their performance, and in fact for most any bias they did have would be overwhelmed by the simple random variation that occurs in year-to-year face-off data. But there appear to be some, like Getzlaf and Ribeiro, for whom the handedness of their face-off opponents does matter, and this will help in unearthing such cases.

Below are splits (FO% vs. left-handed minus FO% vs. right-handed) for the 52 players who have taken at least 100 face-offs against both right- and left-handed opponents every season since 2011-12. I ordered them by increasing standard deviation, so the players towards the top are the ones with the most consistent splits across the four years.

Player 2014-15 2013-14 2012-13 2011-12 Average Std.dev.
Adam Henrique 4.0 3.8 3.9 2.6 3.6 0.7
Claude Giroux 0.5 -0.3 0.8 -1.7 -0.2 1.1
Nicklas Backstrom 5.7 2.2 3.7 3.0 3.7 1.5
Ryan Getzlaf -8.7 -9.0 -7.5 -5.6 -7.7 1.5
Antoine Vermette -2.0 -3.6 -4.8 -1.1 -2.9 1.6
Mike Ribeiro 10.2 9.3 8.9 12.6 10.3 1.7
Henrik Zetterberg 1.8 -1.0 3.5 0.6 1.2 1.9
Mike Richards 2.5 -2.4 -0.8 -0.8 -0.4 2.1
Jay McClement -2.8 -1.4 -4.7 -6.2 -3.8 2.1
Jarret Stoll 5.1 3.1 1.2 0.1 2.4 2.2
Sidney Crosby -3.7 1.0 0.0 -2.7 -1.4 2.2
Eric Staal -3.3 -4.5 0.0 -0.1 -2.0 2.3
Paul Gaustad -0.1 4.3 4.8 1.6 2.7 2.3
David Desharnais -2.8 -1.8 2.8 -0.7 -0.6 2.4
Mikko Koivu -3.1 -2.0 -2.4 2.7 -1.2 2.6
Nate Thompson 4.9 5.0 4.4 -0.8 3.4 2.8
Ryan O’Reilly 0.4 -3.4 2.0 3.2 0.6 2.9
Paul Stastny -6.6 -5.4 -12.0 -7.5 -7.9 2.9
Martin Hanzal 4.3 -0.1 -2.4 2.4 1.1 2.9
Tomas Plekanec -2.7 -1.0 -4.0 -7.9 -3.9 2.9
Sean Couturier 1.2 1.7 -4.8 -1.0 -0.7 3.0
Brandon Sutter -2.6 -5.9 1.4 -1.4 -2.1 3.0
Tyler Bozak -1.4 -2.5 -7.4 -7.0 -4.6 3.1
Sam Gagner 1.1 -4.2 -0.4 3.3 -0.1 3.2
Vernon Fiddler -2.0 0.2 4.8 3.9 1.7 3.2
Brian Boyle 2.4 -5.1 -3.3 -1.4 -1.9 3.2
Derek Stepan 0.4 0.5 7.1 5.1 3.3 3.4
Joe Pavelski -9.3 -3.6 -3.1 -9.4 -6.4 3.5
David Backes 4.1 -3.4 0.7 4.4 1.5 3.6
Patrice Bergeron -2.5 3.6 6.5 1.6 2.3 3.8
Brad Richards -5.7 -9.1 0.0 -3.3 -4.5 3.8
Jonathan Toews -3.3 -1.1 2.5 5.9 1.0 4.0
Kyle Turris 4.0 -2.9 -6.2 0.9 -1.1 4.4
Derick Brassard 8.1 0.0 -1.4 -0.8 1.5 4.5
Joe Thornton 2.6 -6.0 -2.4 3.6 -0.6 4.5
Boyd Gordon 5.0 -6.4 -0.2 0.2 -0.4 4.7
John Tavares 0.5 0.4 9.9 7.0 4.5 4.8
Bryan Little -3.8 0.3 -9.5 1.1 -3.0 4.9
Steven Stamkos 1.2 3.4 11.8 1.8 4.6 4.9
Logan Couture 5.5 0.8 8.2 12.6 6.8 4.9
Gregory Campbell -4.4 7.6 5.0 1.2 2.4 5.2
Ryan Nugent-Hopkins 7.1 -5.7 -1.6 -2.2 -0.6 5.4
Henrik Sedin 6.7 1.5 -6.9 0.1 0.4 5.6
Matt Duchene 3.7 -2.3 7.0 -5.6 0.7 5.7
Pavel Datsyuk -14.0 1.4 -4.0 -3.2 -5.0 6.5
David Legwand 11.3 -2.0 2.1 -3.1 2.1 6.5
Marcus Kruger 13.8 -0.1 -1.1 4.1 4.2 6.8
Frans Nielsen 12.4 -3.9 -4.9 1.1 1.2 7.9
Anze Kopitar -11.6 4.1 6.2 2.4 0.3 8.1
Chris Kelly -18.4 -11.6 -6.1 1.4 -8.7 8.4
Valtteri Filppula 0.2 0.9 -7.0 14.8 2.2 9.1
Cody Hodgson -17.6 1.7 8.2 6.2 -0.4 11.8


Photo credit: mrlaugh@flickr

Beyond Face-off Percentage, Part 1: Quality of Competition

Henrik Zetterberg (photo credit: Anna Enriquez / zomgannalolz@flickr)

The newest stat on faceoffs.net is the Quality of Competition (QoC) face-off percentage: a measure of the difficulty of a player’s face-off opponent pool, consisting of a weighted average of a player’s face-off opponents’ face-off percentages against the rest of the league.

The value is read like a face-off percentage; 50% is average and higher is better. Most players will have values close to 50% but for those who deviate from 50%, it can identify cases where a player has faced unusually strong or weak competition.

To illustrate how this stat works and how it might be useful, we will study two players whose face-off percentage alone may not be telling the whole story:

(All numbers as of 11/7/2014)

Zetterberg has taken 176 face-offs against 39 different opponents this season, but 38% of his face-offs have come against just 4 strong players: Patrice Bergeron, Tyler Bozak, Brandon Sutter, and Ryan Getzlaf.

To more precisely express how difficult Zetterberg’s competition has been, we can take all 39 of those players he has taken face-offs against and calculate their face-off percentages against non-Zetterberg players; then, calculate the weighted average of those face-off percentages, weighting them by the number of face-offs they took against Zetterberg. The result is Zetterberg’s QoC face-off percentage.

Thanks to that skewed opponent pool, Zetterberg’s QoC face-off percentage is an extremely high 55.1%; to put that in perspective, no other player with 100 face-offs is above 53%. That 55.1% is very likely to come down as the season progresses and Zetterberg faces broader competition. According to data from 2013-14, player QoC face-off percentage closely approaches 50% (or perhaps slightly above) as the number of face-offs taken increases.

qoc2013

Now let’s take a look at Malhotra. He is posting amazing face-off numbers as he usually does. But unlike Zetterberg whose opponent distribution is top-heavy with strong competition, Malhotra’s opponent pool is much weaker. So while 62.8% is a marvelous face-off percentage, the fact that he has done it against a QoC of 48.4% suggests that his numbers might slip if he were to go up against as many skilled face-off takers as a top line player like Zetterberg.

So thanks to QoC face-off percentage, we can draw two conclusions:

  • Zetterberg is having a much better year in the face-off circle than his good-but-not-great 52.3% face-off percentage would indicate.
  • Malhotra, while an excellent face-off taker, is perhaps not the superhuman that his raw numbers would make him out to be.

You can view QoC face-off percentage for the league or on individual player profiles.

Photo credit: Anna Enriquez

New features for a new season

Andrew Shaw takes a draw.
Photo credit marymoline@flickr

The 2014-15 season has started and so far not much has changed atop the NHL face-off percentage leaderboard compared to past years. Guys like Antoine Vermette, Manny Malhotra, and Patrice Bergeron are making easy work of their opponents in the circle just like they always do.

Much has changed at faceoffs.net in the couple months since its official roll-out, however, as I’ve worked hard this off-season to bring a lot of cool new things online. Some highlights:

  • Sortable team & player face-off breakdowns: Just about any breakdown of face-off data you want is at your fingertips. Team face-off stats and player face-off stats can be viewed and filtered by home/away, even-strength/power play/shorthanded, and/or defensive/offensive/neutral zones.
  • Team line data: On team pages you can view the forward trios that took even-strength face-offs together and how well they did. For example, last year Pittsburgh‘s Evgeni Malkin was flanked by both James Neal and Jussi Jokinen 359 times in the face-off circle — quite a formidable trio of offensive talent when they had control of the puck, but together they only won 46% of face-offs. On the other hand, last year Boston‘s Patrice Bergeron took 796 face-offs alongside Brad Marchand and Reilly Smith and won an impressive 56% of them.
  • Player linemates: On player pages you can view all the teammates who lined up for face-offs with that player. For example, so far this year through two games, Philadelphia‘s Claude Giroux has taken all but one of his 42 face-offs with Jakub Voracek. The Flyers had better hope that Giroux and Voracek’s 37% face-off percentage together is a small sample size fluke.
  • Scoring: Finally, in an effort to diversify beyond face-offs and provide a little perspective for the face-off numbers, I added scoring statistics and have a leaderboard for scoring.

I have lots more to come, including some advanced face-off stats unlike anything out there. Stay tuned, and tweet me @ctab to let me know if you find any of this useful or have any questions.