One of the many things about Brian Burke that I find irritating is his consistent rejection of the use of data and analytics in hockey. On the one hand, I understand it: guys like Burke, who are on the inside, have a powerful interest in preventing the view that outsiders can have something useful to say about hockey from taking root. On the other hand, I’m quite comfortable saying, on the basis of the stuff that I’ve seen over the past few years, that data and analytics, even if just practiced on the limited information that the NHL bothers to gather, can provide good insights into hockey.
One of the places where Burke does his schtick is at the Sloan Conference every year. I’d tossed in a proposal this year, kind of motivated by Burke being adamant that there was nothing data could tell us. Sadly for me, it appears that that’s gone nowhere, so I’m going to roll the data and information out here over the next couple of weeks. Beats talking about the lockout. I recognize I’m talking to a friendly audience, but this is as much of a proof of concept as anything else: could gathering additional data provide us (or an NHL hockey team spending $50MM+ on hockey players) with valuable additional information?
One of the things that’s baffled me for a long time is why the Oilers power play is so inept. Specifically, I wonder why they’ve basically been a horror show at generating shots for the entirety of the last CBA. The data that the NHL currently publishes does a good job of identifying which PPs are good and which are terrible but it does a poor job of telling us why or otherwise describing the differences between them.
I’ve talked before about what I kind of perceive as being the mystery of Ales Hemsky: he’s a guy who’s scored a lot of PP points but the Oilers haven’t been particularly good at scoring PP goals. If we can agree, in the abstract, that points are only relevant insofar as they indicate a contribution to scoring goals, you’re left with a question about whether or not Hemsky’s any good on the PP. If the way in which he scores a lot of points limits the capacity of the Oilers to score goals, is he really good on the PP?
There’s a lot of smoke around the Oilers problems on the PP but there isn’t a lot of light. The guys in the 300s have their answer: SHOOOOOOOOT! I’ve muttered about really slow movement of the puck and theorized that the Oilers PP doesn’t have enough puck and player movement to generate shots. Some might say that they just have bad players on the PP. Nobody, as far as I know, has engaged in any sort of an objective investigation of the issue, trying to contrast what the Oilers do with what a team that generates a lot of PP shots does.
“Hey,” I thought “this is something that I could do!” I figured that, as a starting point, I could take a kick at figuring out what’s wrong with the Oilers 5v4 PP (I’m just going to say PP from here on out but I’m dealing exclusively with 5v4) by contrasting it with an awesome PP. Enter the San Jose Sharks. The table below summarizes the data for 5v4 between 2008-2012 – in other words, the period when Todd McClellan was in charge of the Sharks. This is an important point in time because the Sharks were pretty middling at generating shots in 2007-08 at 5v4, despite having some awfully talented players. McLellan moved over from Detroit too, a team that’s known for generating a lot of 5v4 shots.
The table is sorted by PP shots/60. You see San Jose at the top and Edmonton at the bottom. The columns are pretty straightforward, although the last one on the right warrants some explanation – it’s simply a quantification of how many 5v4 goals a team has scored in each season, relative to the NHL average. So, for each of the last four years, San Jose’s been about 15 goals better than average; the Oilers about two worse than average.
I’ve tweeted a bit about this off and on over the past few months and when I mentioned I was interested in why the Oilers PP stunk, I was met with a response of “Stop living in the past – the Oilers had an awesome PP in 2011-12.” The Oilers were third in the league in GF/60 on the PP in 2011-12 which is great…except that it was almost all shooting percentage. They finished second in the NHL in shooting percentage and 25th in SF/60. Of the twelve teams who’ve been better than the NHL average of 6.2 GF/60 at 5v4 over the last four years, nine of them were also in the top twelve in terms of S/60. The worst number in terms of SF/60 amongst those teams is 48.7 S/60, which is still considerably ahead of Edmonton’s number last year. In short, the Oilers’ inability to generate shots on the PP is still a problem, no matter how much they scored at 5v4 last year.
I re-watched all of the Oilers/Sharks PPs between 2008-09 and 2011-12 in an effort to generate data that quantifies the differences between the two teams. The table above summarizes the 5v4 data for the two teams in those 16 games. As you’d expect, San Jose is awesome at generating shots – they’ve generated 5v4 shots against the Oilers like some teams generate 5v3 shots and the Oilers have been pathetic – they’ve generated shots like some teams generate 5v5 shots.
(Aside: after doing this, I happened across a post at the Footy Blog with a cool quote from Juergen Klopp, manager of Borussia Dortmund, who might be in the top three teams in the world at the moment. Klopp said:
For me the best analysis is to watch the game again. I know it’s very old fashioned. Tape in, forward and rewind, forward and rewind…a thousand times…spent 5 or 6 hours on a 90 minute game. I haven’t been able to do it any faster. But to be clear: this was my education, no book or seminars or anything from renowned trainers. 10 games a week and I usually started before breakfast.
The post is about how technology could democratize soccer management and is written by Richard Whittall. Whittall comes highly recommended – according to Ben Massey, he’s one of only two writers in the history of the world who is better than Ben Massey. I digress.)
I’m going to start with simply the amount of time that the puck spent in the offensive zone during the PP. It’s startlingly similar. When the Sharks were on the PP, they spent 47.3 minutes, or 61.1% of their total PP time, in the Oilers zone. The Oilers spent 38.97 minutes, or 54.4% of their PP time in the Sharks zone. At the risk of stating the obvious, the marginal difference in PP zone time doesn’t account for the massive difference in shooting rates. If you generate a shooting rate using just offensive zone time as the denominator (which is sort of sensible, given that there aren’t really any shots taken from outside the offensive zone with any realistic chance of going in), you come up with 120.5 S/60 for the Sharks and 61.6 S/60 for the Oilers.
The difference in zone time, slight as it may be, warrants some further examination. The Sharks spent 30.12 minutes outside the offensive zone while on the PP against the Oilers over the past four years and the Oilers spent 32.72 minutes outside the offensive zone against the Sharks – pretty similar. The difference in attempted zone entries is shocking though. The Sharks attempted to enter the Oilers’ zone 159 times in that time; the Oilers attempted to enter the Sharks’ end of the ice just 122 times. Put another way, the Sharks attempted to enter the Oilers end of the ice every 11.4 seconds when they were on the PP and not already there. The Oilers averaged 16.1 seconds of time outside the offensive zone per attempted zone entry.
First, I want to look at what happened during those zone entries. I broke the zone entries into two types – carries and dump-ins. Passes over the blue line were treated as carries. Interestingly, to me anyway, there wasn’t really a huge difference between the two teams in terms of the mix of carries and dump-ins. The Sharks attempted to carry the puck in 71.1% of the time; the Oilers attempted to carry it in 73% of the time. Basically the same.
Let’s look at the success rates on those attempted zone entries. The success rate on attempted carries is basically the same – if the Sharks had successfully entered the zone by way of carrying the puck three more times or the Oilers three fewer, they’d be tied. There’s not much to pick between the two teams here. The differing success rate on the dump-ins seems a bit more significant. This is just an observation but the Sharks seem to run dump-ins as a more deliberate play. They seem to happen more when Ryan Clowe is on the ice and they seem to involve firing the puck hard around the boards for Clowe to recover. Oilers’ dump-ins seem to be more ad hoc, like a planned carry has broken down and you end up with some guy backhanding it in with nobody going hard for the puck or Souray just kind of aimlessly bombing it in from centre ice.
Similarly, the Sharks’ carries into the zone just look cleaner, something I talked about here – they pretty clearly look to isolate a defending player in a 2 on 1 at the blue line and it works a lot. I wrote in the summer about one of their zone entry plays – they’ve got a few of them, but they all seem to be intended to build a framework from which 2-on-1′s are created at the blue line, if the entry is even contested.
On this data then, you can attribute some of the Oilers’ lack of zone time against the Sharks to an inability to gain the offensive zone by dumping the puck in and recovering it. Some of that is made up for by their superiority in gaining the line when they attempt to carry the puck in. Really, once an attempt to gain the offensive zone is made, it’s close to a wash: San Jose succeeded 69.1% of the time against Edmonton; Edmonton succeeded 68.9% of the time against San Jose. The more critical difference here seems to be in the amount of time that’s needed to make an attempt – Edmonton took 41% longer to put an attempt at the Sharks’ blue line together.
I’m going to leave this here for now but want to make a couple of final points. First, an obvious area to go back and look at is why the Oilers take, on average, so much more time than San Jose to attempt an entry of the offensive zone at 5v4. Is this an example of the utility of a puck moving defenceman? San Jose, of course, acquired Dan Boyle in 2008, while the Oilers have run a number of different defencemen as their PP guy since then: Tom Gilbert, Corey Potter, Sheldon Souray, Barbaro, Jeff Petry – it’s been a bit of a revolving door, with neither Souray nor Potter being particularly impressive as puck moving guys. That might be a question I try to address as I move forward with this. My gut feeling is that this is going to prove not to be much of a factor – the Sharks have taken a lot of shots when Boyle hasn’t been on the ice – and that it’s more to do with the Oilers lacking a good structure when it comes to exiting their own end of the ice and entering the Sharks’ zone but we’ll see.
Second, it should be obvious that this is potentially very useful information, if you had it on a league wide basis. If you’re a guy charged with running a successful PP, how can you have any degree of certainty about where you’re good and where you need to improve if you don’t have the thing broken down into a series of digestible parts that you can then compare against other teams? Just knowing who’s good doesn’t help you too much if you’re trying to run an NHL team; you need to know why they’re good. Data like zone entry success rates and seconds per zone entry attempt would provide a useful measuring stick. If it was gathered.
Next post: A closer look at the causes and implications of the Oilers’ dithering in attempting to gain the offensive zone.Email Tyler Dellow at firstname.lastname@example.org