Tuesday, November 26, 2013

New Jersey Home/Road Split: Undercounting or Style of Play?

Home/road goalie splits for the New Jersey Devils this season:

Home:  .942 Save %, 20.98 SA/60
Road:  .910 Save %, 27.12 SA/60

A difference of 6 shots per 60 is a massive gap, and likely is at least partly due to some small sample size randomness.  However, New Jersey has long been suspected of undercounting shots at their home rink.  What is curious, however, is that the team save percentage is much higher at home than on the road, which is not what would be expected if it was purely a scorer counting issue (see, for example, Martin Brodeur's career splits, which work out to .911 at home vs. .914 on the road, numbers more consistent with a theory of systemic undercounting).

Extra Skater gives possession data at the team level, and those stats indicate that New Jersey is the lowest-event team in the league no matter where their games take place:

Most Low Event Home Teams (Combined Fenwick events per 60 minutes):
1. New Jersey, 58.2
2. Minnesota, 70.9
3. Buffalo, 73.6
4. Columbus, 74.0
5. Calgary, 75.4

Most Low Event Road Teams (Combined Fenwick events per 60):
1. New Jersey, 71.3
2. Edmonton, 74.7
3. Pittsburgh, 74.7
4. Minnesota, 74.7
5. Columbus, 76.9

It certainly seems possible there is some undercounting still going on in New Jersey since they come in so far below all other teams in home Fenwick events, although it should be noted that there were two other teams that had a similar split in terms of a much lower game pace at home compared to on the road.  The Devils' differential of 13.1 only narrowly edged out Ottawa's 12.3 and Buffalo's 11.8.

It is also interesting that the Sabres and Senators have very different goaltending splits during 5 on 5 play (although these are very tiny sample sizes):

Buffalo:  .906 at home, .934 on the road
Ottawa:  .911 at home, .940 on the road
New Jersey:  .931 at home, .911 on the road

The two most common explanations for a team giving up far more shots on the road would seem to be either a difference in the way shots are counted or a team trying to lower average shot quality by giving up more ice from the less dangerous areas of the defensive zone.  Either way, what you expect to see is that the team's goalies do a little bit better on the road than expected, which is again why the Devils' splits seem abnormal.

Looking at the overall population, there is some correlation between pace and save percentage in 2013-14, although it should be noted that the data shows little relationship for 2012-13.  The teams with notably different home/road splits are also quite different from 2012-13 (New Jersey had a difference of just 2.3, albeit in the same direction), with only Carolina and Dallas coming in as substantial outliers over both seasons (both of them playing with a higher pace at home than on the road).

More evidence is needed to show whether a team's pace has any kind of sustained impact on its percentages (in general it probably doesn't), but while they are no longer using the infamous neutral zone trap, it is clear that the New Jersey Devils are focusing more than any team at suppressing shots and chances at both ends of the rink.

Monday, November 18, 2013

Why Canada Doesn't Have a Goaltending Problem at Sochi (If You Believe in Large Sample Sizes)

With the Sochi Olympics lurking on the horizon, the early season fortunes of goaltenders have caused a lot of glee or consternation among hockey fans around the world, depending on how their nation's puckstoppers have come out of the gate.  With respect to goaltending, however, it is important to remember that talent is revealed in the large sample size (see here for one of the definitive takes on that theme).  There has been a lot written lately about how Canada no longer has top-level elite goaltending, but in my opinion that was an overreaction to a shortened lockout season where it was purely coincidence that the country's best seemingly all had off-years.

It's easy to get distracted by the flashy new models, especially when they are off to scorching starts, but looking at only the established goalies with a track record of success Canada simply does not come up short at all relative to other nations.

Goalies with at least 4000 SA since 2010-11 (ranked by save percentage):

1. Henrik Lundqvist: .925 on 5313 SA
2. Pekka Rinne: .922 on 5388 SA
3. Roberto Luongo: .921 on 4359 SA
4. Mike Smith: .920 on 4217 SA
5. Carey Price: .919 on 5624 SA
6. Kari Lehtonen: .919 on 5286 SA
7. Antti Niemi: .918 on 5290 SA
8. Jonathan Quick: .918 on 4771 SA
9. Cam Ward: .918 on 5211 SA
10. Craig Anderson: .917 on 4587 SA
11. Marc-Andre Fleury: .916 on 4820 SA
12. Ryan Miller: .916 on 5590 SA
13. Jimmy Howard: .915 on 4923 SA
14. Jonas Hiller: .914 on 4493 SA
15. Niklas Backstrom: .914 on 4064 SA

The three goalies that seem likely to be named to Canada's roster are all in the top 5.  Luongo and Smith are both off to solid starts this season, while Price has been outstanding.  The three have them have combined for a .922 save percentage this season, which is very much in line with their historical numbers.  In fact, the trio have been very consistent, with the exception of one lockout-shortened 48 game season:

Luongo/Price/Smith Combined:

2013-14:  .922
2012-13:  .907
2011-12:  .922
2010-11:  .922

When framed like that, it looks pretty blatant that everyone was panicking over an obvious outlier.  The problem remains of picking one guy to be the starter, since when it comes to crunch time you can't combine stats and play with an average of three guys.  Even elite goalies have off games, and in short tournaments it's always better to have the hot hand rather than the superior talent (although the best goalies are also the ones with the best chance of running hot or, perhaps equally important, avoiding a very costly slump).  Overall, though, there is no question that Canada has proven goaltending talent that is at least competitive with the other top nations.

Obviously the parameters of the above list rule out a number of goalies who are likely in the running for Olympic spots (netminders such as Rask, Varlamov, Bobrovsky, Crawford, Schneider, Lehner, Holtby, Bernier, Reimer, etc.), and I'm certainly not saying that none of those youngsters deserve spots, but it is much more difficult to identify their true talent level because of the relatively small sample size they have behind them in their shorter careers.  Russia, in particular, seems to be facing a tough choice between Semyon Varlamov and Sergei Bobrovsky, both of whom narrowly missed the cutoff for this list but would have come in on the lower end anyway at .914 and .916 respectively, and the U.S. and Finland both have a number of quality contenders and limited spots, which will force some interesting roster decisions.  At the end of the day, though, I expect that this Olympics will be similar to the last one in that the top nations will all have capable goaltending and it will come down to which teams play the best overall that determines the final result.

Thursday, November 14, 2013

Why the Oilers Don't Need Bryzgalov

The Edmonton Oilers didn't need to sign Ilya Bryzgalov, because goaltending isn't going to be make the slightest bit of difference for them this season.  And that's even assuming he is an upgrade on what the team currently has on the roster.

It is true that the Oilers have an abysmal team rate of .881 so far this season, with both incumbent starter Devan Dubnyk (.881) and backup Jason LaBarbera (.858) off to horrific starts.  As a result, goaltending has been the scapegoat in some corners for the team's early struggles.  While it is obvious that getting more saves would have led to more points in the standings, the reality is that the Oilers are a terrible team in a stacked division that probably wouldn't make the playoffs if they had prime Dominik Hasek tending the twine.

The bad news is that Edmonton currently has a a 44.9% score-tied Fenwick, indicating that they are being routinely dominated by their opposition.  The even worse news is that so far the team has played the majority of its schedule against the inferior Eastern Conference, going just 0-5-1 so far in games against Western Conference opponents.  The top five teams in the Pacific Division currently all have records of .600 or better, and are a combined 40-14-7 against the rest of the league.  If Metropolitan Division teams can run the Oilers off the ice, then it's going to be no contest against the heavyweights of the West.

Even though it is early, and some teams records are skewed based on their number of inter vs. intra-conference games, the wheat seems to already be separating out from the chaff in the Western Conference.  Unless you're a big believer in Winnipeg or Dallas, it looks like nine teams will probably be challenging for the eight spots, and the current 8th place team in points percentage is Los Angeles at .639 (and while the Kings just lost Jon Quick for a while, they have played a tough schedule made up of primarily Western Conference opponents).

For the Oilers to be in contention for a spot, they'd probably have to have a goal differential of something approaching the Kings' +8, a difficult proposition considering Edmonton ranks second-last in the Western Conference at 2.35 goals per game.  That implies a team save percentage of .930+, and that's not even taking into account the fact that the Oilers' shot ratio is skewed because they have spent so much time trailing (if their goaltending held them in games longer, the other team would be pouring even more rubber on net and pushing the required break-even save percentage even higher).

Look at Dallas and Montreal, two teams that have very similar offensive results to the Oilers so far, while also possessing above 50% score-tied Fenwick scores and elite goalies off to outstanding starts (Lehtonen .932, Price .933).  Despite all that, both teams currently sit 5th in their divisions, with Montreal slightly better off because they are currently in position to grab the wild card crossover spot.

Ilya Bryzgalov's career high seasonal save percentage is .921.  That came three years ago, when he was 30.  Bryzgalov does not seem like the type of the goalie who would age well, given that he relies more on a blocking style and does not have top-drawer athleticism and lateral movement.  He was shredded in the KHL during the lockout, put up a .905 over the past two seasons under the microscope in Philly, and will likely take a bit to play himself into game shape after spending most of this season waiting for the phone to ring.  In short, the best case scenario for what Bryzgalov can offer the Oilers isn't even remotely close to the elite range that they're going to need to turn things around, and even if Bryzgalov could hypothetically put up .930 goaltending the team is still sunk because of their slow start and tough division and questionable backup goaltending (although I do expect Dubnyk to re-discover his game as the season goes on).

Edmonton's season is already lost, and it's because their team is awful in all areas, not just goaltending.  Giving a declining goalie a look-see won't save anything, and if the goal is to look to the future I don't think a bad stretch of 14 games changes the fact that the 27-year old Dubnyk would seem to be a much better bet than the 33-year old Bryzgalov.  I don't see the urgency that prompted the move.  If the Oilers really wanted to solve their long-term goalie problems they should have either taken a run at one of the elite goalies who might be available through trade (someone like Ryan Miller) or waited until July to try to sign somebody.  Signing Bryzgalov is too little too late, and it would be better for Edmonton to get more information on Devan Dubnyk and give him a chance to re-prove himself than to hopefully lose slightly less often with another goalie who likely won't figure into the future of the franchise anyway.