Apr 292010
 

If you have not yet read Part I and Part II of this series, you should probably do that now so you will better understand Part III.

In this part I wanted to take a look at individual goalies and see how they compare to the average. The following is a list of the 19 goalies I used to create the goalie performance by age average chart that you see in Part II and if you click on their names you will be shown a chart of their performance compared to the average performance.

Chris Osgood
Chris Tererri
Craig Billington
Curtis Joseph
Dominik Hasek
Ed Belfour
Glenn Healy
Jeff Hackett
Jocelyn Thibault
John Vanbiesbrouk
Kirk McLean
Martin Brodeur
Mike Richter
Mike Vernon
Olaf Kolzig
Patrick Roy
Ron Tugnutt
Sean Burke
Tom Barasso

I’ll leave it as an exercise to the reader to go through each of the charts and draw whatever conclusions you can but there appear to be two different charts. The first is a typical curved chart where a goalie improves early in his career and tails off later in his career. There are of course varying degrees of this curve from the extreme like Jeff Hackett to a more moderate curve like Ron Tugnutt. The other type of chart which is quite common is the one where the goalie enters the league at quite a high level and then tails off over time. Again there are varying degrees as to which this tail off occurs from the extreme in Jocelyn Thibault or Kirk McLean to a more casual drop of as with Mike Vernon.

It is generally believed that the two best goalies of the past 20-25 years are Patrick Roy and Martin Brodeur. Not as often mentioned is Dominik Hasek and I can only assume that is because he doens’t have the win totals or Stanley Cups of the other two partly because of the teams he played for and partly because he started his career late compared to Roy and Brodeur. But, in the prime of his career he was truly dominating and in my opinion was by far the best goalie in the NHL through the late 1990′s and into the current decade. So, lets take a look at how these three stack up against each other.

Clearly all three have been better than the average of the other 19 goalies, but I was actually a little surprised to see how little better Brodeur has been for much of his career. Four times in Brodeur’s career has he performed below the average of the other 19 goalies at the same age where neither Roy or Hasek ever performed below the group average at any age. The other conclusion one must draw from this chart is simply how good Hasek was, particularly late in his career. Roy had dominating years in his early to mid 20′s but from age 29 on clearly Hasek was the more dominant goalie. As for Brodeur, he has had a few excellent seasons but generally speaking has been a step below the Roy and Hasek at all ages. The only other goalie who could possibly be considered as a similar talent to these three goalies is Ed Belfour who you could argue had a career quite similar to that of Brodeur.

In part IV, which I’ll either post tomorrow or early next week, I’ll take a look at a few current goalies in the middle of their careers to see if we can gain any insight into what phase of their career they are in and what the future might hold for them.

Apr 282010
 

Earlier today I posted an article showing how a goalies save percentage varies by age. It was pointed out that one of the flaws in that analysis is that I didn’t account for the fact that over time the average NHL save percentage has varied, and has generally increased over time. In fact, the change from the 1980′s to the 1990′s is quite significant. As a result I decided it was important enough to take the next step and account for variations in league wide save percentages.

To accomplish this I took each goalies save percentage and divided it by the league wide save percentage for that year which essentially tells us how much a goalie was better or worse than his peers in that given year. Anything greater than 1 meant the goalie was better than the average goalie and anything less than 1 meant the goalie was not as good as the average goalie that year. I then performed the same analysis using this ratio number instead of straight save percentage.

How do Goalie Age

The end result is that a goalies peak years generally start sooner than seen under the straight save percentage analysis and the drop off in a goalies latter years is more pronounced as well. Generally speaking a goalie will have his best years between ages 22 and 34 after which the drop off is fairly pronounced. This isn’t true for all goalies though as the truly elite goalies such as Roy, Belfour, Hasek and Brodeur played above their peers well beyond age 34 but for the majority of goalies it is downhill once you get past your early 30′s.

Note: In the above chart I only included ages for which data was available for at least 3 goalies and I only included years where a goalie played at least 5 games. This was done so as to not skew the chart at the edges and the result is only ages 19-41 are shown though Barasso played at age 18 and Hasek played until age 43.

Apr 282010
 

I was inspired to write this article by a post over at Behind the Net where they discussed goalie even strength save percentage by age. In that article they came away with the conclusion:

Analyzing the data every way I can think up, there is no evidence whatsoever of any relationship between goalie age and even strength save percentage.

But, as I pointed out in the comments there are two serious flaws with their analysis. The first is that they do a linear regression analysis which is probably not the best tool to use as one can reasonably assume that a goalies skills do not progress linearly as he ages. One would expect a goalie would improve early in his career, plateau for a few years, and then regress in the latter years of his career. A hypothetical example might see a goalie have the following save percentages for his 10 year career: .900, .905, .910, .915, .920, .920, .915, .910, .905, .900. Fitting that data to a linear equation would net a slope of zero indicating no relationship between age and save percentage. Clearly from the data though there is probably a connection between age and save percentage.

The second problem I pointed out in the comments was in the second part of the analysis where they just looked at goalies with 3 years or more of data. The problem with this is that one can probably expect the difference in a goalies skill level at age 26 and at age 28 to be minimal, if anything at all. Skill level variation by age is likely to take a lot more than 3 years to identify. The reality is if a goalie only played in the NHL from age 26 to 28 that was probably the peak of his career and he simply wasn’t good enough to make the NHL to have a save percentage to use before and after that point, but since only NHL save percentage was used we can’t know how the goalies skill level might have improved before age 26 or tailed off after age 28.

To fix these issues one really should only look at goalies where you have a lot of data over many years and not look at it using linear regression which isn’t going to work. So what I have done is identify all of the goalies that have played in the NHL for at least 14 seasons and whose careers continued at least into the 2000-2001 season. The list of goalies that meet these qualifications are: Curtis Joseph, Tom Barasso, Sean Burke, Ed Belfour, Dominik Hasek, Olaf Kolzig, Jocelyn Thibault, Chris Osgood, Martin Brodeur, Patrick Roy, John Vanbiesbrouk, Mike Vernon, Ron Tugnutt, Jeff Hackett, Craig Billington, Glen Healey, Kirk McLean, Mike Richter and Chris Tererri. That list includes quite a variety of goaltenders including hall of famers and career backups and everything in between. I then took averaged their save percentages by age and came up with the following chart.

Save Percentage by Age

From that chart there appears to be a very strong relationship between age and save percentage. Before age 22 and after age 40 there are only a small number of data points so the chart goes a little wonky at the edges but from age 22 to age 30 there is a fairly steady improvement in a goalies save percentage. Between the ages of 30 and 34 a goalies save percentage plateaus before starting a steady decline until age 40. This is very much as one would expect and it only takes looking at the data in the proper way to confirm our expectations.

Apr 152010
 

I have always believed that goaltending is by far the most important position in hockey and have claimed it can make or break any teams season. I have claimed that the main reason that the Leafs have failed to make the playoffs post lockout is because of bad goaltending. Many others have scoffed at this claim blaming everything from bad defense to bad offense (which is mostly not factually true) to poor coaching, to a combination of all of the above. I have seen others claim that goaltending would account for at most four or five games a year. So, I have undertaken a bit of a study to attempt to figure out how important goaltending really is and how many points in the standings poor goaltending can cost you or great goaltending can gain you.

Most goaltending studies I have seen, and done myself, have to do with comparing goalies from one team to the next. The problem with this is people can easily choose to dismiss the study with claims like ‘but team x has such a bad defense you cannot blame the goalie for that’ and to some extent there is some validity in this claim (though I do not believe it to be as much as many do). There have been other studies that attempt to factor out the defense issue by coming up with some sort of shot difficulty rating based on shot type and defense. I believe that this has some merit and improves the validity of the study but people will simply jump in and claim that not all shots from the same distance are equal and teams with bad defense will inherently give up more difficult shots so the shot quality analysis is still far from perfect. Again, there is some merit to this.

So, with all that in mind I set out to study goaltending in a way that eliminates the quality of a team’s defense in a way that most sane people cannot dispute: compare goalies who play on the same team. If we are comparing two goalies who play on the same team we immediately eliminate the ‘but he plays on a bad team’ argument because they are playing behind the same players.

I collected all the goalie statistics from the 5 regular seasons since the NHL lockout of the 2004-05 season. For each team and season I identified each team’s starting goalie (the goalie with the most starts) and then grouped all other goalies who played for that team in that season and merged their statistics into a combined backup goalie statistic. For example, this past season Jonas Hiller was the starter for the Anaheim Ducks and JS Giguere and Curtis McElhinney also played for the Ducks so Giguere and McElhinney’s stats were combined into a single team backup stat. The statistics I am interested in are save percentage and points earned for their team and the number of games started from which we can calculate points earned per start stat for the starter and the combined backup. I next subtracted the backups points per start from the starters points per start and the backups save percentage from the starters save percentage. Here is an example for the Anaheim goalies.

Goalie Starts W L OTL PTS Pts/Start SV%
Jonas Hiller 58 30 23 4 64 1.103 0.9182
JS Giguere 17 4 8 5 11 0.9000
C. McElhinney 7 5 1 2 10 0.9167
Backups 24 9 9 3 25 1.042 0.9055
Starter-Backup 0.0618 0.0128

So, from that table we see that Jonas Hiller had a save percentage 0.0618 higher than his backups and produced more points for his team in the standings at a rate of 0.0128 per start. Now since that last stat is pretty meaningless I prorated it to 82 games and over the course of 82 games Hiller would produce 5.07 additional points in the standings over his backups.

Continue reading »

Apr 132010
 

Washington vs Montreal

Washington was the run away leader in the eastern conference finishing 18 points ahead of second place New Jersey and 33 points ahead of 8th place Montreal. Washington was a middle of the road defensive team but was a truly dominant offensive team scoring on average 3.75 goals per game, more than a half a goal per game more than the Canucks who were the second most offensive team and 1.24 goals per game more than the Canadiens who ranked 26th in the league. Montreal has next to no chance of winning this series unless Jaroslav Halak can outright steal it for them. As good as Halak is, that is not likely to happen and Montreal should just hope they can steal a game or two. Washington in 5.

New Jersey vs Philadelphia

Philadephia is one of the most inconsistent teams in the league, largely due to their suspect goaltending but Brian Boucher has in the past shown he can get real hot for short stretches (he had 5 straight shutouts a couple years back) and the Flyers offense is pretty good so it isn’t inconceivable that the Flyers could upset the Devils. Brodeur is still a very good goalie but has from time to time over the past couple seasons show that he can be beaten and the Devils defense isn’t quite as reliable as it was a few years back. All that said, Parise and Kovalchuk give the Devils two elite level offensive stars and they have an underrated complimentary group surrounding them so I think this series will go to the Devils. New Jersey in 6.

Buffalo vs Boston

The easy prediction is that there probably won’t be many goals scored in this series, especially on the Bruins side of the ledger. Boston was the lowest scoring team in the NHL and the Sabres were the fourth best defensive team in the NHL and the Bruins were second best. Buffalo clearly has an edge having a much better offensive production but the games should all be very close meaning anyone could win with a few lucky bounces. I’ll stick with the Sabres and their better offense though it will be a long series. Buffalo in 7.
Pittsburgh vs Ottawa

For the third time in four years Pittsburgh and Ottawa will meet in the playoffs with Ottawa winning the first series and Pittsburgh the second so this is a rubber match of sorts. Neither Ottawa or Pittsburgh are all that great defensively as these two teams ranked 19th and 20th in the NHL in goals against average and have the lowest goals against average of any of the playoff teams. In Pittsburgh’s case they have just been consistently mediocre defensively for much of the season and in Ottawa’s case it has been result of extreme inconsistency of their goaltenders. Pascal Leclaire has had a dismal season and while Brian Elliot has looked excellent for stretches he still has too many weak games to be considered a relaible goalie. If Pittsburgh gets on Elliot early this could be a short series, but if they let Elliot and the Senators gain confidence they could be a tough opponent for the Penguins and could very well take the series. I personally am not confident in Elliot and I think the good Penguin offense will get the better of him. Pengiuns in 5.

Continue reading »

Apr 082010
 

If you polled hockey fans who the top contenders are for the Stanley Cup, four of the most frequent answers you will get will be Washington and Pittsburgh from the eastern conference and San Jose and Chicago from the western conference. What these teams have in common are very good groups of offensive forwards with multiple star players and some pretty good defensemen to go with them. But what they also have in common are question marks in goal that they will have to overcome if they are to go deep into the playoffs.

San Jose Sharks
We all know about the Sharks playoff failures of recent years and much of the blame has been placed on forwards like Joe Thornton and Patrick Marleau. Starting goalie Evgeni Nabokov has been an excellent regular season goalie and been OK in the playoffs but he hasn’t stolen a series for the Sharks and his post Olympic play has to be a concern for Sharks fans. As you are all probably aware, Nabokov had a poor Olympics, and in particular, a really bad game against the Canadian team that cost the Russians a shot at a medal. Since the Olympics he hasn’t been any better having posted an 8-7-1 record with a 3.11 goals against average and a very mediocre .897 save percentage and in 16 post Olympic games he has given up 4 or more goals 7 times (including 5 goals Sunday against possible first round opponent Colorado). That isn’t going to cut it in the playoffs. We know Nabokov can play better, but will he turn his game around come playoff time?

Chicago Blackhawks
The Blackhawks goaltending is an interesting case study into inconsistency. They lead the league in shutouts and are 6th in goals against average but are 7th worst in the league in save percentage. Cristobol Huet can go on stretches where he looks solid and reliable (in his first 21 starts this year he only gave up more than 3 goals once) but then for other stretches he can look downright awful. The end result though is that he is unreliable. Then you have youngster Anti Niemi who has been the better and more reliable goalie this year and has a respectable .913 save percentage but he too has been inconsistent. In 33 starts he has 7 shutouts which is pretty phenomenal (Brodeur leads the league with 9, but he started 73 games) but in those 33 starts he has also given up 4 or more goals 8 times which is not so good.

Washington Capitals
The Washington Capitals are not unlike the Chicago Blackhawks as they too have a somewhat unreliable veteren (Theodore) and a quality young goalie (Varlamov) that may or may not be ready to carry the load. I have a little more confidence in the Capitals goaltending though as they have been a little more consistent. As a group they only have 3 shutouts, but they have fewer disaster games too and with the Capitals offensive capabilities that might be good enough but it still has to be a concern for Capitals fans.

Pittsburgh Penguins
There may be some that are surprised to see the Penguins make this list but lets look at the facts. As a team the Penguins have the worst goals against average of any playoff bound team and have the fourth worst save percentage in the NHL. Marc-Andre Fleury has a very mediocre .904 save percentage over the course of the season and a pretty bad .892 save percentage since the Olympics. Since February 1st he has started 20 games and given up at least three goals in 14 of them and four or more goals 6 times. We know Fleury can play well enough to win a Stanley Cup, but his performance this season, and over the past couple months in particular, has not been good enough. To make matters worst for Penguins fans, yesterday on TSN it was pointed out in 17 games against division leaders the Penguins have just 3 wins. Of the top four teams in the east, I think the Penguins are the one team most likely to face a first round playoff exit.

(cross posted at HockeyAnalysis.com)