Capitals vs. Bruins - Tracking puck possessions
Cam Charron
March 06 2013 12:31PM
There's been some talk about the importance of hitting in the hockey blogosphere lately. Most of it has come on Twitter in the wake of the Edmonton Oilers trading for Mike Brown and to whether or not Brown's hitting will make a lick of difference to the Oilers lineup.
My gut reaction is "no, no it won't". I did a big of leg-work in this post at the Backhand Shelf that showed "hits" "giveaways" and "takeaways" were subjective statistics that didn't really mean anything. Every scorer in every building has a different definition of a hit. What I wanted to see was whether actual hits lead to turnovers in any given game.
So I watched the Washington Capitals-Boston Bruins game Tuesday night and will probably watch a couple more games until I conclude anything, but I wanted to get some suggestions as to how I can improve my model. In basketball, the number of possessions is easy to deduce from the scoresheet: Shots Taken + Turnovers + Blocked Shots - Offensive Rebounds. There are more ways that a possession can "end" in a hockey game:
Dump In: A puck shot into the attacking zone directed at nobody in particular.
Dump Out: A puck shot out of the defending zone directed at nobody in particular.
Shot: After an offensive chance, the defence recovers the puck.
Pass: An intercepted pass.
Takeaway: A forced turnover where the defending player targets the offensive players' stick or the puck to win control.
Hit: A forced turnover where the defending player targets the body to win control. Also counts when a hit forces the offensive player to make a bad pass.
Faceoff: If control from the previous sequence is changed off the ensuing face-off (this was to ensure that teams alternated possessions)
Period: The end of a period, or, in the case of Tuesday's Washington-Boston game, the overtime goal.
So just to see how possession of the puck changed hands… the Bruins had 193 possessions and the Capitals had 194:
| Possession ended by... | Washington possessions | Boston possessions |
|---|---|---|
| Dump In | 40 | 40 |
| Dump Out | 25 | 27 |
| Shot | 21 | 27 |
| Pass | 40 | 44 |
| Takeaway | 29 | 26 |
| Hit | 22 | 16 |
| Faceoff | 16 | 13 |
| Period | 2 | 2 |
The RTSS counter gave Washington 23 hits and Boston 22. I had them at 16-22, so either the Capitals were credited with some 'phantom' hits or their definition was different than mine. The big difference was in giveaways and takeaways, of which they were plenty on both sides. I had giveaways at 44 for Washington and 40 for Boston, but the scorer had them 12-6.
Anybody with some suggestions on how to improve this? I'm not looking to find out which players are good at these sorts of things, I just think it's important to quantify how the puck changes hands in the NHL.
To me it looked like the capitals responded when Ovi leveleled Rask. That kind of "hit" by the captain seemed to really create momentum and fired up the team.
What I look for in games are "game changing" events. For example with the leafs when Orr or Mclaren fights the leafs sometimes but not always respond. Also Phaneuf was better with his hits last year but he seems to be lost out there at times.
And sometimes a goal will do it. I find kadri or macarthur are behind this measure. That is "game changing" goals. But a player like Kessel, I noticed recently tends to score when it doesn't matter so to speak.
Maybe you can make a separate list for Even Strength and power-play possession rate. It is really frustrating how the statisticians can have varying numbers. I imagine it was even worse back in the day.
@leaferfan
Sometimes the Leafs "respond" to a fight or big hit or a song between action, and sometimes they don't?
How is that different from "those events have no discernible impact on the game"?
If you're suggesting a bit hit pumps up the players and they're "hungrier" for blood or goals or a soft-baked macaroni... Doesn't that also mean you're suggesting NHL players are incapable of fully motivating themselves? That seems like a long shot, considering how much work it takes to make and stick in the league..
@brett. Both teams are trying to outdo each other. But what I look for is "turning points" in the game that cause the momentum to swing.
@leaferfan Sounds like you're looking for some narrative from the analysts on tv.
Check out Boucher scouting...he has very detailed stats..along these lines..for ind. players
Cam, what was your definition of "changing possession?"
Basically when a player had the puck on his stick and had the space to make a "hockey move". Pretty subjective definition, but that's the thing with hockey.
What about fumbles? You know a player has control, usually in the neutral zone or offensive zone and just loses late puck?