The Leafs and the Numbers
As most readers know, I am more than a little sceptical about the usefulness of hockey statistics, but I’m always willing to take another look at the subject. The most interesting team in the league for those who put a lot of stock in the numbers is probably the Toronto Maple Leafs. The data guys were all pessimistic about the Leafs before the season and they continue to be pessimistic about them now despite their good start.
The biggest single problem that I have with the analytics is the narrative that has emerged to support them. I don’t think that narrative describes hockey. It goes something like this: “Attempted shots – shots, missed shots and opponent’s blocked shots – measure puck possession and the key to winning is puck possession.”
Toronto’s “puck possession” numbers are awful – they are outshot too often and by too much. The assumption is that they have been blessed with an inordinate share of puck luck. Therefore they aren’t likely to keep winning. The argument is not entirely without merit. There is a correlation between shot differential and winning percentage (although it is not particularly powerful and it is not clear how meaningful it is.) Over the course of a season good teams tend to outshoot their opponents and bad ones tend to get outshot.
That said, I don’t think hockey is a puck possession game and in any case I don’t think attempted shots measure puck possession. Teams have essentially the same number of possessions per game, and I doubt if there is much difference in actual possession time. Losers might actually have the puck more!
(I think the key is speed and puck movement. The team that moves the puck the most quickly is the team that gets the most and best chances. There are two separate factors at work in a hockey game. First, there is the team’s ability to control the play – making sure the puck moves slowly toward their own net and moves quickly towards the opponent’s net. That’s about denying open ice to the opponents and creating open ice for the good guys.
A Taylor Hall quality player – I think he is probably the best player in the West – obviously helps a team accomplish those things, but he is still only one skater out of five. Where Hall really makes a difference is when the Oilers do manage to create some ice. That is the second factor. Does the team have finishing ability? When the team gives Hall the puck and open ice, he’s usually going to do something good with it and create a scoring chance. But when the Oilers as a group do not slow down the opponents or find a way to move the puck quickly, their stars become non-factors.)
While “puck possession” numbers do correlate with winning at a league level, there is no apparent link at the game level. Good teams tend to outshoot their opponents, but teams – good and bad – actually do better in games when they are outshot.
The Leafs? In the past three years plus 11 games, their record when they outshoot opponents is 31-44-10. When they are outshot, they are 74-50-15. I understand the qualms data analysts have with the Leafs, but “They get outshot too often” isn’t a particularly compelling argument when you look at numbers like that. When they outshoot opponents the Leafs play like a 69 point a year team. When they are outshot, they are a playoff team with 95 points.
To my eye the Leafs are pretty good without the puck, they do pretty well generating speed through the neutral zone and they certainly have finishing ability. I expect their team shooting percentage to fall somewhat as the season goes on and I don’t think they are a team good enough to get 105 points – their current pace – but I do think they will fight for a playoff spot all year long.
Even if their puck possession numbers suck.