Friday, December 31, 2010

It Doesn't Matter How Good His Teammates Were, He Still Had To Make the Saves

"Hey, I just back from the new shopping mall. Gotta give it up for our mayor, that guy is the best ribbon-cutter in the town."

"He is? How could you possibly go about trying to determine that?"

"Well, I was there, and he was the guy in charge of opening the mall, and it got opened. Can't argue with results."

"OK, but that's kind of a simple thing, isn't it? I mean, any public figure can give a short speech, work a pair of scissors and pose for a few photos. The mayor is just the guy that gets assigned to show up and do it, that doesn't mean he is the best."

"Sure it does, you still have to cut the ribbon. Doesn't matter how easy you think the job is, it still needs to get done. You don't see anybody else cutting the ribbon, do you?"

"No, but that's because it is the mayor's job, not because other people couldn't do it."

"Who cares about other people? It's his job and he did it, that's all that matters, that's why he deserves the credit."

"It is? There were mayors before him that did it just as well and there will be mayors after him that will do exactly the same thing. Why does it matter who actually does it? You don't think that guy that narrowly lost the election two years ago could have done it?"

"I don't want to talk about what-ifs, just what actually happened. Yesterday the mall wasn't open, and today it is. I don't know why you hate the guy so much, why you won't give him any credit, you're probably just jealous. I was there when they opened the new library too, sure he may have flubbed a line or two and dropped the scissors twice but he showed his mental toughness by bouncing right back and when the big moment came he got the job done."

"I'm not arguing that he didn't get the job done. I'm saying that his job was fairly easy, and he did not make much of a difference in doing it. The mall and the library are both just as open right now as they would have been if another politician was wielding the ceremonial scissors. Giving credit for an easily replaceable effort makes little sense at all, you're just being overly impressed by the privileges of the guy's position."

"Obviously you don't understand anything about politics. Since that guy became mayor, he has cut the ribbons at 3 grand openings, while all the other losing candidates in that election have combined for zero. How can you argue with those stats?"

"Again, I'm not disputing that those accomplishments happened. I'm disputing their value. Of course our mayor did the job, but he did it no better than somebody with similar qualifications would have done it. The difference between him and those other guys with respect to grand openings was entirely a matter of opportunity, not a matter of skill. Why is that something to be celebrated? I'm completely baffled here."

"Say whatever you want, he can't hear you because of all of the freshly cut ribbons in his ears. You geeks never give that guy any credit, he's the most underrated mayor ever. Haters gonna hate, I guess. We're done here, I'll catch you later."

Tuesday, December 28, 2010

The Two Sentence Argument against Chris Osgood

"It's not easy to win in this league, otherwise everybody would be doing it. I don't know how many goalies have played here in the last 15 years that I've been here, but I'm still here and I'm still wanted. That's what matters most and accounts for more than anything else. I'm a winner. That's all I do."
Chris Osgood

On the occasion of Chris Osgood's 400th win in the National Hockey League, I feel compelled to throw up this brief post. Every goalie needs to be evaluated in the context of their team environment. That's especially crucial for those who want to rely on statistics like wins and Cups in their analysis. My best attempt to concisely summarize Osgood's team environment is the following:

Chris Osgood's career record in playoff series where his team had a 20+ point regular season advantage over their opponents:
7 wins, 1 loss

Chris Osgood's career record in playoff series where his team had an advantage of less than 20 points over their opponents:
8 wins, 8 losses

(You might want to pull out a third sentence as well, either to establish context or in case that other guy whips out an anecdote about Montreal beating Washington or some other rare event: Over the course of Osgood's career, teams with a 20+ point advantage are 33-7 in playoff series).

When the Detroit Red Wings were way better than their playoff opponents, they nearly always heavily outplayed and outshot them. It's not too surprising that the stronger team with a big edge in scoring chances usually won.

On the other hand, when his teammates weren't far better than the opposition then it was pretty much a coin flip for Osgood's teams in the playoffs. When two even teams meet, you'd expect them both to win about half of the time. If one of them has a great, game-changing clutch performer then you'd expect his team to win more often, yet that wasn't the case. Throughout Osgood's playoff career in Detroit the Red Wings were mostly the higher-ranked team even in the closer matchups, yet with home ice advantage and a "winner" in net they still lost as often as they won.

The context is further displayed by the results of the other goalies who played in Detroit. Not only was Osgood often relegated to a backup role come playoff time, but overall the Red Wings really didn't suffer with other goalies in net. Here's a third line that really should be added to the two above to paint a complete picture:

Chris Osgood's teams' career record in playoff series where Osgood was sitting on the bench as the backup goalie:
9 wins, 4 losses

Expressing records like this can help drive home the point that certain goalies who won lots of jewellery did not, in fact, outperform others in the playoffs who won none. They merely played for much stronger teams, and when they did not have that advantage on their side then they were not big enough difference-makers to lift their team results above average.

Chris Osgood deserves credit for the determination and competitiveness that have allowed him to beat the odds and carve out a long and lucrative big-league career. Career milestones are a fitting time to show him that appreciation, but any attempt to portray him as one of the best of his peers is misinformed, career win totals notwithstanding.

Tuesday, December 14, 2010

Follow the Money

A lot of people put stock in what NHL general managers have to say about different players and goalies around the league. It makes sense that these talent evaluators should have a better than average ability to rate hockey players, the problem is that few are going to go on record as being critical of anybody, and sometimes it's difficult to tell if a quote is a bland nicety or a real endorsement. Furthermore, nobody knows a player better than his own team's management group, but in almost all cases they are going to support the player in any kind of a public setting. Vezina voting gives us some indication, but there remains a difference between rating the best goalie of a particular season and the best goalie in general.

When you want to know what people really think, and not just what they say they think, it is usually better to focus on actions than words. That's why I think there is some value in looking at the size of the paycheques of goalies around the league. As with any numerical ranking, it's often good to bring in some outside knowledge to inform the rankings (insane longterm deals, home-town discounts, ELC/RFA/UFA years, salary inflation, to name but a few things that have an impact), but at the end of the day nobody pays anybody millions of dollars a year without expecting significant performance in return. And on the flip side, a general manager can go on for as long as he wants about how the goalie on his winning team is underrated and mentally tough and makes the big saves and is a great teammate, but when he refuses to open the purse strings come free agency time that is a stronger indication that his objective viewpoint is something altogether different.

Using Hockey Zone Plus and Cap Geek, I was able to put together career salary histories for most of the experienced starting goalies since 1990, and then applied a factor to adjust for the league average goalie salary in each season.

Here are the total adjusted earnings figures:

1. Patrick Roy, $76,550,000
2. Dominik Hasek, $55,510,000
3. Ed Belfour, $54,840,000
4. Martin Brodeur, $51,000,000
5. Mike Richter, $49,830,000
6. Curtis Joseph, $49,000,000
7. Tom Barrasso, $36,720,000
8. Nik Khabibulin, $35,340,000
9. Olaf Kolzig, $33,200,000
10. Sean Burke, $32,560,000
11. Jose Theodore, $27,410,000
12. Roberto Luongo, $27,280,000
13. J.S. Giguere, $25,430,000
14. Felix Potvin, $24,520,000
15. Kirk McLean, $24,400,000
16. Bill Ranford, $23,450,000
17. Chris Osgood, $22,940,000
18. Evgeni Nabokov, $21,320,000
19. Marty Turco, $20,920,000
20. Miikka Kiprusoff, $20,350,000

Contract timing and the adjustment factors make it unlikely that this list would come out with a perfect ranking, but it still comes out surprisingly well, especially when you look at tiers rather than specific rankings. The top four are correct, although admittedly very few people would put them in that order. Mike Richter shows one of the flaws of this method, that a goalie who was entrenched for a long time on a large market team with a spend-happy GM is likely to get paid disproportionately to everyone else. It's not too hard to make the argument that Joseph's repeated free agency paydays from several different franchises are more impressive than Richter cashing in on the '94 Stanley Cup run.

Barrasso, Khabibulin, Kolzig and Burke were a solid group of goalies that make up the next tier. Jose Theodore is the surprising leader of the the younger group of goalies, although this is the last year he will be ranked ahead of Roberto Luongo. Luongo projects to end up in Joseph/Richter territory by the end of his lifetime contract in Vancouver, and quite possibly higher depending on your assumptions of salary inflation.

The other interesting guy to point out is #17 on the list. If Chris Osgood was really the #2 goalie of the last decade, as some claim, then he needs to immediately sue his agent for gross malpractice. I think the reality is that, in the vote done with their owners' dollars, the league's general managers just weren't all that impressed by Osgood.

Here's a measure of peak effectiveness, each goalie's best 5 consecutive years in adjusted salary:

1. Dominik Hasek, $29,650,000
2. Patrick Roy, $29,271,000
3. Curtis Joseph, $25,297,000
4. Mike Richter, $23,424,000
5. Ed Belfour, $21,884,000
6. Nik Khabibulin, $21,726,000
7. Martin Brodeur, $21,103,000
8. Olaf Kolzig, $20,926,000
9. Roberto Luongo, $20,651,000
10. Tom Barrasso, $20,328,000
11. Jose Theodore, $18,719,000
12. Marty Turco, $16,580,000
13. Miikka Kiprusoff, $16,201,000
14. J.S. Giguere, $15,915,000
15. Kirk McLean, $15,888,000
16. Evgeni Nabokov, $15,793,000
17. Bill Ranford, $14,604,000
18. Henrik Lundqvist, $14,484,000
19. Tomas Vokoun, $13,705,000
20. Sean Burke, $13,536,000

This time Hasek beats out Roy for the top spot, with the two of them both well clear of the field. I think it's safe to say that Nikolai Khabibulin has had some pretty good representation over the years, while Brodeur likely left a good chunk of change on the table because he preferred to play in New Jersey. A few current goalies are slowly creeping up this list, in a couple of years Henrik Lundqvist will be just outside of the top 10.

Just one caveat, the adjustment is likely over-correcting for post-lockout goalies. With a maximum salary level, with more goaltending talent around the league and with restricted free agents getting paid big dollars earlier than ever before, there is no longer the huge salary disparity between the top veterans and the newcomers that was seen in the late '90s.

Wednesday, December 8, 2010

GMs and Goalie Stats

The 1994-95 NHL regular season was very unusual. A lengthy lockout shortened the schedule to just 48 games per team, and to make the scheduling work every team only played against opponents within their own conference. The condensed schedule also gave teams fewer off-days, meaning they had less of an opportunity to catch up with the goings-on around the rest of the league.

The short season made it tough for all awards voters to identify the league's best, but it had to have been especially difficult for the league's general managers required to vote on the 1995 Vezina. Many of them would not have seen much at all of the other conference, and likely would only have seen the best goalies in their own division 3-4 times. Based on this I expect that 1994-95 was probably the season where GMs were most likely to rely on statistics when filling out their award ballots.

If that's true, then looking at the voting results should give some insight on how general managers rate goalies based on their performance numbers (the full Vezina ranking can be found here). How did they fare? In my opinion, not very well. Most of them voted for Dominik Hasek, but that shouldn't have been a very difficult choice at all given that Hasek was the defending Vezina winner and led the league in GAA, shutouts and of course save percentage, where he crushed the field by .013. The other rankings were less clear, and some of the choices left something to be desired.

In particular, there were three voters that seem to have completely failed the test, the trio of league decision-makers who rated Mike Vernon as the best goalie in the league.

Compare the stats:

Vernon: 19-6-4, 2.52, .893, 1 SO
Hasek: 19-14-7, 2.11, .930, 5 SO

I really hope those were Western Conference GMs who just saw Vernon really good against their own teams and didn't feel comfortable ranking Eastern goalies that they hadn't seen play. Even in that event they still made a very poor decision, but it would have been completely embarrassing for them if they actually looked at everyone's numbers and decided that Vernon had the best season based on wins and losses.

Detroit had a terrific team as usual that season, with a defensive unit led by Nicklas Lidstrom, Paul Coffey, Slava Fetisov and Vladimir Konstantinov, plus their usual strong group of forwards. Backup Chris Osgood actually had better numbers than Vernon (14-5-0, 2.26, .917). On the other hand, when Hasek wasn't in net Buffalo's goaltending numbers were 3-5-0, 3.86, .864.

Any given shot was 67% more likely to go in against Vernon than against Hasek. Vernon allowed 3.21 goals per 30 shots against compared to Hasek's 2.10. If you were to swap Vernon's goal support in Detroit with Buffalo's goalscoring during Hasek's first 30 games of the season (excluding one short relief appearance), it would have had a dramatic effect on the records of both goalies. Vernon would have had a losing record at 11-15-4, while Hasek would have improved to a spectacular 22-3-5. And that's based on raw goals against without even taking into account the fact that Vernon faced nearly 7 fewer shots against per game.

It wasn't even remotely close, that's the point I'm trying to make.

Looking at the Vezina votes overall, they ended up being split around a number of goalies, which was perhaps to be expected given the peculiar circumstances. In addition to Hasek and Vernon five other goalies received at least one first place vote, only two of whom ended up in the top 10 in save percentage, and 15 goalies ended up with at least one vote. No other season has ever seen more different goalies get named on Vezina ballots than 1994-95.

If you remove Hasek from the sample, since he was so obviously the best goalie that even a voter who never saw him play and was just going by traditional numbers like GAA or shutouts should still have been able to figure out that the Dominator was the most deserving, here are the correlations between the Vezina voting and other statistics among all other goalies with 20+ games played that season:

GAA: -.591
Win Percentage: .589
Wins: .536
Shots/60: -.534
Shutouts: .455
Save Percentage: .290

That makes it seem pretty apparent that most early '90s NHL general managers rated goalies based on wins and the strength of the defence in front of them. That's scary stuff, and is yet another reminder that we should be cautious when using historical Vezina voting results to rank goalies.

Friday, December 3, 2010

The Swedes Have It Right

Do you want to know who is leading the Swedish elite league in goaltender wins this season? I don't know, and as far as I can tell there's no way to find out on their official website. They simply omit wins as a stat category.

If you want to sort Swedish goalies by statistics, you can only sort them by save percentage, GAA, total shots against and total saves against. That's it. They apparently don't seem to care that they aren't providing us with the crucial information that lets us know whether league-leader Victor Fasth is a "martyr goaltender" pointlessly racking up numbers on a bad team, or whether #2 ranked Alexander Salak really knows how to make the big saves in the clutch. How are us North Americans supposed to make snap judgments about these goalies' characters and their ability to perform under pressure when they are leaving out the crucial information of how good their teammates are?

It's quite possible there is some other way to find out which Swedish goalie has the most wins, but I just like the fact that they obviously don't consider that to be of any importance, given that they don't even bother to show the numbers.

Same thing with the International Ice Hockey Federation. Go to their website, and you won't find win/loss records either. Not only that, but like the other European sites their default sort is by save percentage (so much so that the link you have to click on to see goalie numbers is called "Goalkeepers (SVS%)", as shown here at the site for the 2010 Olympics). In contrast most North American sites will rank by GAA first, and even the NHL's own stats summary page for goalies ranks them by wins.

The only reason anybody gives any weight at all to goalie wins is because of the long tradition of tracking them and the related myths told by generations of hockey people and broadcasters. Europe probably doesn't have the same tradition, or else perhaps somewhere along the line somebody decided to speak up and point out how stupid it was to track team results at the individual level. Either way, good for them. Given that they don't care about wins and losses, how do you think Swedish and Finnish coaches are evaluating their young goalie prospects? No doubt they are using almost exclusively save percentage, and with the recent European goalie invasion it's pretty hard to argue with the results.

Tuesday, November 30, 2010

Occam's Razor

Roberto Luongo is 16-2-2 with a .926 save percentage while representing Canada in senior men's international competitions. Before he turned pro, he also played great in two world junior tournaments and helped two different teams qualify for the Memorial Cup.

Luongo's career professional playoff numbers against every team other than the Chicago Blackhawks are 16-12, 2.15, .931.

Combine that with the international numbers, and Luongo is a sparkling 32-14-2, 2.07, .929 in postseason and international games as a pro that did not involve the Blackhawks.

Against Chicago in the playoffs, Luongo is 4-8, 3.52, .888.

Occam's Razor says the simplest solution is more likely to be correct. So, which solution seems simpler and better suited to the facts?

1. Luongo chokes in pressure situations, and just happened to either play behind powerful defences or get lucky every single time he played in big games, other than when he played against Chicago in the playoffs where his true nature was revealed.

2. Luongo is just fine in pressure situations, and he and his teammates matched up poorly against Chicago the past two playoff seasons.

Friday, November 19, 2010

The Wrong Numbers, Part 2

(With about thee-quarters of this post already written, I noticed that my prior post on the wrong numbers in hockey had been linked to from the Leafs Central message boards, and in an interesting coincidence it was in a post where occasional commenter here Seventieslord was arguing exactly the same thing that I am about to claim in this post. I'll credit him where appropriate for a couple of things that I added on to strengthen my own argument).

Point totals in hockey seem to be magic numbers. The players who score the most are generally considered to be the best players, and players are routinely described to be playing well if they are racking up the points and not playing well if they aren't.

The problem is that isn't always true. There may be lots of reasons why a player is scoring or not scoring points other than his level of play, such as the type of situations his coach is putting him in, the shooting luck of his teammates, the play of the opponents he is matched up against, and just general puck luck. It is often the case that a player who outscored another in the playoffs was the better player, but this is far from always true, and that means it is a mistake to assume that a higher point total trumps all.

In my opinion, the 2009 Conn Smythe Trophy went to the wrong guy. I don't want to take anything away from Evgeni Malkin (well, other than the trophy they gave him, I guess), but I'd argue that Sidney Crosby was the Penguins' best player. There have been many Malkin vs. Crosby arguments debating which player stepped up in the Finals, which one the Red Wings focused their defensive attention on, which one carried the team in the key games in the earlier rounds, which one was the bigger leader, and so on. At the end of the day, I think there were really only two numbers that mattered: 31 and 36, the respective point totals of Crosby and Malkin. Like it or not, those numbers coloured the rest of the debate, and since 36 > 31, Malkin was the popular choice as Conn Smythe Trophy winner.

The way I see it, Crosby was the better player and the point totals are misleading. Crosby scored more goals and more even strength points than Malkin. With Malkin on the ice, the Penguins scored 41 goals and gave up 21. With Crosby on the ice, the team scored 40 and allowed just 14, in a similar amount of ice time, which indicates he and his linemates may have had a better two-way effort (which also came against tougher opposition). From those numbers and from watching the games, I don't think Malkin was outplaying Crosby, just outpointing him.

The reason that Malkin won the points race was power play scoring. Malkin scored 16 power play points to Crosby's 10. Not surprisingly, however, both stars were on the ice for the majority of the Penguins goals, given that they both played heavily on the team's first PP unit. There were 16 PPG that both were on the ice for, and Crosby and Malkin each had one additional goal where they were on the ice but the other was not.

During the regular season, both players got points on 75% of the team power play goals they were on the ice for. In the playoffs Malkin had points on 94% of his on-ice goals, while Crosby was at just 59%. It was certainly not the case that somebody else replaced Crosby's contribution (both Crosby and Malkin each scored more PPP than the rest of Pittsburgh's forwards combined). I think that the simple explanation is that puck luck worked to the benefit of Malkin and the expense of Crosby.

I watched all the power play goals Pittsburgh scored with either player on the ice on the NHL game highlights on Youtube, and noted how each goal was scored. Here is the breakdown of how they got their points:

Solo effort or good play to create the goal: Malkin 4, Crosby 3
Converting a routine rebound: Malkin 0, Crosby 2
Routine pass to a teammate who created the goal: Malkin 7, Crosby 4
Fortunate bounce: Malkin 5, Crosby 1
Third assists: Malkin 0, Crosby 3

The first Penguins' power play goal of the playoffs I counted as a fortunate bounce for both players, as Malkin's attempted pass across the crease was deflected by Martin Biron off of Crosby's skate and into the net. The other four goals counted as lucky for Malkin included: a point shot that bounced in off of Malkin's knee, a Malkin pass that was batted by an opposing defender right to Mark Eaton who promptly scored, an attempted pass to Crosby on a 2-on-1 that was deflected into the net by a defender for an overtime game-winner, and Brad Stuart knocking the rebound into his own net after Chris Osgood made the initial save on Malkin.

In all likelihood, Malkin and Crosby played at a similar level on the power play in the '09 playoffs, Malkin just ended up on the scoresheet more often. Even if Malkin did create a few extra scoring plays compared to Crosby 5-on-4, I don't think it makes up for Crosby's better overall performance.

Much was also made of the Stanley Cup Final scoring differential, but I'm still not sure that Crosby was any worse than Malkin in the Finals, even discounting the fact that the Red Wings obviously targeted Crosby as their #1 defensive priority. Crosby and his linemates were simply snakebitten that entire series. Bill Guerin and Chris Kunitz, Crosby's most frequent linemates, combined to score 0 goals on 32 shots. Guerin missed several point blank chances, and Crosby himself hit several posts and was robbed repeatedly by either Chris Osgood or Henrik Zetterberg. Guerin and Kunitz had almost the same shot rate against Detroit as they did in the other three rounds, yet nothing was going in. By my eyes, that certainly wasn't Crosby's fault. I think the hockey gods deserve at least as much credit for "shutting down" Crosby as Lidstrom and Zetterberg.

In contrast, Malkin's most frequent linemates Ruslan Fedotenko and Max Talbot combined to shoot 17% in the Finals. Malkin himself scored 8 points, but again it was a case of him being on the right side of some puck luck. Two of Malkin's routine power play assists came in that series on goals by Letang and Gonchar, and two more assists came on lucky breaks, one a horrible rebound by Osgood left for Fedotenko to bang in, and the other a bounce off of a forechecking Malkin's skate right to Talbot, who promptly scored. Malkin also got credit for the Brad Stuart own goal mentioned above.

There are two additional arguments for Crosby that I'm stealing from Seventieslord at Leafs Central. First, Crosby shouldered a heavy load with faceoffs, leading all players in the playoffs by taking a 37.7% share of his team's draws while winning a respectable 53% of them. Secondly, Malkin cost his team quite a bit of time spent on the penalty kill by taking 18 minor penalties, nearly double the number of any other player in the playoffs, while Crosby was only whistled for 7 minors.

While I think Crosby was superior, Malkin did play very well. Malkin also hit his share of posts and created chances where the puck luck wasn't on his side, which means it perhaps wasn't so unrighteous that he got some of the bounces along the way. It is also incorrect to completely discount routine plays, as the ability to consistently make routine plays under pressure is part of what differentiates a great player. Not every goal is an amazing end-to-end rush, after all. That said, the rate that those routine plays get turned into goals can certainly vary quite a bit in the short term.

In nearly every other playoff season, Malkin would have been a very deserving Conn Smythe winner. I just don't think he was in 2009, as the evidence supports Sidney Crosby. Unfortunately, many hockey observers have a tendency of looking at the wrong or the simple numbers and ignoring the importance of context. Even to self-professed stats-hating hockey observers, the power of a single number can be very strong indeed, and at the end of the day 36 points were just too much to ignore.

Thursday, November 11, 2010

The Wrong Numbers

I had been thinking about putting up a post on the problems of evaluating hockey players by observation, but Kent Wilson saved me the trouble with his recent comprehensive post on that very topic. I fully agree with his conclusion that subjective observation alone is inadequate in judging hockey talent. I also agree that the stats vs. scouting debate is often presented as a false dichotomy and tends to verge into strawman territory, because nobody really uses only one method or the other.

You won't find many objective analysts who claim to never watch hockey. You will, on the other hand, find many journalists and fans that will tell you that they ignore stats and rely only on their terrific scouting abilities and crystal clear memories. I find that interesting, because I'd argue that in almost every case they are simply wrong about that. They are being affected by many different variables, biases, groupthink, etc., and the evidence is pretty good that one of the strongest factors is indeed statistical performance.

I've already pointed out, for example, how GAA leaders are almost always voted to the year-end All-Star team. Similarly, Art Ross Trophy winners are almost always Hart finalists. Since the lockout year of 1994-95, every Selke Trophy winner has scored at least 20 goals, and Rod Brind'Amour was the only Selke winner with a plus/minus rating below +17. If the stat sheets weren't affecting the votes, then those are some remarkable coincidences.

The truth is that everyone relies on some numbers, whether they want to admit it or not. What drives stat guys the most crazy is when people argue that the newer advanced metrics are flawed and wrong, and then go ahead and base their judgments, often unwittingly, on traditional stats that are far worse.

One of the best examples of how people were misled by a single number is Joe Nieuwendyk's Conn Smythe in 1999. There is pretty much one reason that Nieuwendyk was named playoff MVP, and it was that he scored a record-setting 6 game-winning goals in the '99 postseason.

Was Nieuwendyk really that clutch? He did have a knack for scoring goals late when the game was tied. However, goals that break the tie aren't the only important ones. For example, if your team is trailing late then it's impossible to get the game-winner without first knotting up the score. That makes the tying goal a pretty important goal as well, even though it does not appear anywhere on the stat sheet.

One of the reasons Dallas won the Cup that year was that they were great at coming from behind, a rarity for the Dead Puck Era. The Stars were 4-4 in games where they trailed after two periods, a phenomenal record given that the other 15 playoff teams combined to go just 9-42 in the same situation. In all, Dallas scored 10 goals that tied the game in the third period in that playoff season. Somewhat strangely, Nieuwendyk's clutchness didn't seem to manifest itself when his team was losing late. He didn't score any of the goals, and only assisted on one of them.

The Stars also scored 5 goals that gave the team a two-goal lead in the third period (not including empty netters), goals that effectively sealed the victory. Again, none of those goals were scored by Nieuwendyk, and he only assisted on one.

Let's drop game-winning goals and look at a different definition of clutch scoring that takes into account both of the above situations as well. Counting all points on goals scored in the third period or overtime that either tied the game, gave Dallas the lead, or gave Dallas a two-goal lead (empty-netters excluded) gives the following scoring totals in the '99 playoffs:

Modano: 3 goals, 7 assists, 10 points
Nieuwendyk: 5 goals, 3 assists, 8 points
Langenbrunner: 5 goals, 3 assists, 8 points
Lehtinen: 5 goals, 1 assist, 6 points

Nieuwendyk wasn't any more of a clutch scorer than the other guys, he just got the recognition because of the arbitrary nature of game-winning goals. His goals helped Dallas win games, of course, but so did the goals that Modano and Lehtinen were scoring to tie the game up in the first place.

Three of Nieuwendyk's GWG and both of his OT goals came in the first six games, all of them won by Dallas against significantly inferior opponents (Edmonton and St. Louis). In the finals Nieuwendyk had just 2 goals and 1 assist while Modano's line made the difference (Modano had 7 assists in the Finals). I'm not necessarily against that, I would prefer the trophy to be awarded to the best player throughout the playoffs rather than simply the best player in the last series, but that is atypical for a Conn Smythe Trophy winner.

The final reason Nieuwendyk never should have won it over Modano is because Modano played a way tougher role. We don't have play-by-play records or shift charts from the '99 playoffs, but I'm sure they would have shown Ken Hitchcock matching Mike Modano or Guy Carbonneau up against the opposition's best players. I bet the majority of Nieuwendyk's goals and points in those playoffs came against the other team's second, third or fourth lines.

Modano was a big part of the Stars' 90.5% penalty kill, a PK that ran two forward pairings almost exclusively (Carbonneau/Keane and Modano/Lehtinen). Modano averaged 2:59 per game on the PK, compared to Nieuwendyk's 0:04. At even strength, Modano played 17:29 per game while Nieuwendyk played just 14:43. On the power play the two were closer (4:11 for Modano compared to 3:38 for Nieuwendyk), which again reflects how Nieuwendyk was used in an offensive role.

Modano played more minutes, played tougher minutes, played better defence, scored more points on clutch goals, scored more overall and carried the team in the Finals, yet somehow Nieuwendyk was the MVP? That does not compute. Ask anybody who voted on it and they'll tell you how Nieuwendyk brought leadership and was clutch, but I'd bet that what was really shaping their perceptions was the 6 GWG. The Conn Smythe should have gone to either Modano or Buffalo's Dominik Hasek. With Ed Belfour in the mix as well, I think Nieuwendyk would have been, at best, a distant #4 on my MVP list.

The moral of the story is that, no matter how much of an anti-stats hard line you profess, the numbers are going to affect your perceptions anyway, either directly or indirectly. After all, it's pretty tough to watch a hockey game on TV without being fed a bunch of numbers, or hearing the broadcasters talking about so-and-so's scoring totals and making claims about players that are largely based on their stats to date. Given all that, you might as well be aware of the right stats, rather than being misled by traditional numbers.

Sunday, October 31, 2010

Top 5 and Top 10 Save Percentages

This is a bit of a data dump post, but I wanted to post the results after compiling the number of top 5 and top 10 save percentage finishes for goalies in the post-expansion era. Note that evidence suggests that team effects were greater in the 1970s and 1980s than in the 1990s and 2000s (see this post for example), which means that it isn't fair to directly compare, say, a goalie who played on a bad team in the 1970s or a goalie who played on a great team in the 1980s with one of today's netminders.

With that in mind here's the list, with the first number being top 5 finishes and the second the number of top tens:

Patrick Roy: 9 / 15
Tony Esposito: 8 / 12
Dominik Hasek: 9 / 11
Billy Smith: 6 / 11
Ken Dryden: 6 / 8
Bernie Parent: 6 / 8
Chico Resch: 5 / 7
John Vanbiesbrouck: 4 / 7
Roberto Luongo: 3 / 7
Rogie Vachon: 1 / 7
Martin Brodeur: 4 / 6
Ed Belfour: 4 / 6
Tom Barrasso: 4 / 6
Kelly Hrudey: 3 / 6
Dan Bouchard: 3 / 6
Andy Moog: 3 / 6
Pete Peeters: 5 / 5
Gump Worsley: 4 / 5
Jacques Plante: 3 / 5
Denis Herron: 3 / 5
Doug Favell: 3 / 5
Reggie Lemelin: 3 / 5
Curtis Joseph: 2 / 5
Cesare Maniago: 2 / 5
Mike Richter: 1 / 5
Don Beaupre: 1 / 5
Tomas Vokoun: 4 / 4
Jeff Hackett: 3 / 4
Mark Fitzpatrick: 3 / 4
Nik Khabibulin: 2 / 4
Don Edwards: 2 / 4
Miikka Kiprusoff: 2 / 4
Glen Hanlon: 2 / 4
Mike Liut: 2 / 4
Sean Burke: 1 / 4
J.S. Giguere: 1 / 4
Bob Essensa: 1 / 4
Ed Giacomin: 1 / 4
Gerry Cheevers: 1 / 4
Grant Fuhr: 1 / 4
Evgeni Nabokov: 0 / 4
Marty Turco: 3 /3
Roman Cechmanek: 3 / 3
Rolie Melanson: 3 / 3
Mike Palmateer: 2 / 3
Bunny Larocque: 2 / 3
Olaf Kolzig: 2 / 3
Ron Hextall: 2 / 3
Jose Theodore: 2 / 3
Guy Hebert: 2 / 3
Daren Puppa: 2 / 3
Manny Fernandez: 2 / 3
Tim Thomas: 2 / 3
Niklas Backstrom: 2 / 3
Bruce Gamble: 1 / 3
Glenn Hall: 1 / 3
Gilles Villemure: 1 / 3
Gilles Meloche: 1 / 3
Chris Osgood: 1 / 3
Felix Potvin: 1 / 3
Ron Tugnutt: 1 / 3
Henrik Lundqvist: 1 / 3
Ryan Miller: 1 / 3
Rick Wamsley: 1 / 3
Manny Legace: 0 / 3

As a postscript, here are the goalies with 500 career games played since expansion who did not make the cut:

Mike Vernon (2/2), Bill Ranford (0/1), Kirk McLean (0/2), Greg Millen (0/1), Jocelyn Thibault (1/1), Ken Wregget (0/1), Arturs Irbe (1/1), Gary Smith (0/0), Tommy Salo (0/0), Roger Crozier (1/2), Dwayne Roloson (2/2)

Tuesday, October 26, 2010

Don Cherry and Swedish Goalies

One of the current goalie hotbeds is the country of Sweden. Six different Swedish netminders made their NHL debuts in either this season or last, to raise to 11 the total number of Swedes who have played in goal since the lockout. Henrik Lundqvist remains the nation's best, but this year Anders Lindback has emerged as a surprise in Nashville, Jonas Gustavsson has played well for a surprising Toronto squad, and Robin Lehner has started to make the case that he might be the future solution to Ottawa's goaltending woes. Despite all this Swedish success, the best may still be yet to come in the person of Jakob Markstrom, considered by many to be the top-rated goalie prospect in the world today.

It was not always the case, however, that the Tre Kronor produced top-level goalies. In fact, there were only a handful of Swedes who played net in the NHL in the 20th century. The entire list is as follows: Tommy Salo, Pelle Lindbergh, Tommy Soderstrom, Hardy Astrom, and Goran Hogosta.

Salo and Lindbergh are likely familiar to most hockey fans. Salo had a lengthy NHL career (526 games played), although he may unfortunately be remembered most for his gaffe against Belarus at the 2002 Olympics. Lindbergh won the 1985 Vezina Trophy, then had his career tragically cut short the following season when he died in a car crash at the age of 26.

The other three had much less memorable careers, although I suspect many Canadian hockey fans have at least a passing familiarity with the name of Hardy Astrom. Astrom played just three years in the NHL, but has achieved a level of infamy as a result of a few stories told by TV personality Don Cherry on CBC's Coach's Corner and on his personal Rock 'em Sock 'em videos.

The way Cherry tells it, Astrom was a bumbling goalie that couldn't stop soft lobs from center ice in practice. It's entirely possible that Astrom let in some stinkers, especially while getting bombarded behind the hapless Colorado Rockies defence. Still, does it make sense that a guy who represented Sweden in the 1976 Canada Cup and two other world championships and attracted enough attention to play pro hockey in North America at a time when Europeans were underrepresented in the NHL was laughably inept?

Sounds to me like this guy might just have been stigmatized by a bad goal or two at the wrong time, a la Tommy Salo. Let's see what the numbers say. Here are the results for all Colorado goalies from 1979-80 to 1980-81. Breaking it into Astrom vs. everyone else, we get the following:

Hardy Astrom: 3.76, .870
All other goalies: 4.20, .854

I'm starting to think Don Cherry may have been exaggerating just a little.

Astrom was pretty unlucky in the goal support department, because his winning percentage lagged most of his teammates. That might have led to a perception that he wasn't a "winner". Yet for all Cherry likes to rag on Astrom, the coach still gave him 49 games in net in 1979-80. Swede jokes may entertain Canadian TV audiences, but by what economists called revealed preference it is unlikely that Cherry really thought his Swedish goalie was truly that horrible, based on the coaching decisions he made with his job on the line.

The numbers suggest Astrom was likely a pretty average netminder, especially when you factor in how bad the Rockies were. I bet Cherry coached quite a few other goalies who were worse than Astrom during his tenure in the NHL, and it seems kind of unfair (but perhaps not surprising, given Cherry's general anti-European sentiment) that he seems to have picked out one Swedish guy all these years later to be the butt of his jokes.

Tuesday, October 19, 2010

Questioning Ed Giacomin

(Like Tyler Dellow, I usually feel like I don't have much to talk about early in the season. Anything involving goalies is going to necessarily be an attempt to find meaning in impossibly small sample sizes. My posts will be mostly focused on historical items until we can be in a better position to guess at how things are shaking out.)

If you were asked to list off the easiest goalie jobs in NHL history, there would be a number of dynasty teams that would come immediately to mind. Right after those powerhouses, I think a high ranking on that list should be reserved for the starting role on an Original Six team shortly after expansion in the late '60s and early '70s. That was a position that was pretty much guaranteed to make you look better than you were.

To nobody's surprise, the teams that were already full of NHL talent dominated the expansion teams in the first few seasons after the league doubled in size. This effect lasted for quite some time as new expansion fodder kept getting tossed into the mix throughout the decade, until the late '70s when the Hawks, Leafs and Wings had fallen back into the pack and a number of expansion teams including the Flyers, Islanders, and Sabres had become legitimate contenders for the Cup.

There were 11 Hall of Fame goalies that were active during the period from 1968 to 1975, but a handful of them were at the end of their careers (Plante, Worsley, Hall, Bower, Sawchuk), and another (Billy Smith) was suffering through the growing pains on an expansion team and had yet to make his mark. That leaves Ken Dryden, Tony Esposito, Gerry Cheevers, Ed Giacomin and Bernie Parent as the goalies who had their peak in the post-expansion period.

Or, to express it in a slightly different but perhaps more meaningful way, Montreal's goalie, Chicago's goalie, Boston's goalie, New York's goalie, and Bernie Parent.

The Leafs and Red Wings might have been able to put somebody in the Hall of Fame too if they hadn't spread the workload around. Both teams used 14 different goalies in those 8 seasons, and Roy Edwards was the only one who played in over 200 games. The Leafs did have both Plante and Parent on their team at times during this period, which helped both of their resumes although both of them would have become honoured members even without their tenures in Toronto.

If team effects had the potential to create Hall of Famers, then which goalies got lucky and which ones were unlucky? I'd submit Ed Giacomin as probably the worst of the lot. If you look at the Rangers' year-by-year GAAs against Original Six teams compared to expansion teams, you start to get a sense of the lack of balance in the league:

1967-68: 2.76 vs. Original Six, 1.88 vs. Expansion
1968-69: 3.15 vs. Original Six, 1.94 vs. Expansion
1969-70: 2.80 vs. Original Six, 2.14 vs. Expansion
1970-71: 2.73 vs. Original Six, 1.98 vs. Expansion
1971-72: 3.10 vs. Original Six, 2.06 vs. Expansion
1972-73: 3.31 vs. Original Six, 2.35 vs. Expansion
1973-74: 4.26 vs. Original Six, 2.67 vs. Expansion
1974-75: 4.52 vs. Original Six, 3.07 vs. Expansion
Period Averages: 3.14 vs. Original Six, 2.34 vs. Expansion

That's a 34% increase in GAA when playing against a fellow Original Six team. The Rangers also shut out the expansion teams 39 times, compared to just 17 blankings of their older foes.

Giacomin was voted the best goalie in 1966-67, which appears to be an impressive feat given that there were still only five other teams that season. However, that was an unusual year where most of league's netminders were in platoon situations. Roger Crozier was the only other goalie who played in more than 44 games, and considering Crozier played on a much weaker Detroit team it looks like Giacomin was named the best goalie more or less by default.

Giacomin also was voted the top goalie in 1970-71, a year where he finished second in save percentage with an impressive .922. Although this was Giacomin's career year, he still never should have received that honour, not when Jacques Plante posted an incredible .944 save percentage in just 5 fewer games played. In addition, Giacomin's journeyman backup Gilles Villemure had very similar stats (2.30, .919 compared to Giacomin's 2.16, .922), which suggests that the Rangers were making it tough for the opposition to score.

In this period Giacomin got many of the typical edges of a goalie playing for a defensive, disciplined team. New York faced fewer opposing power plays than average every year between 1968 and 1975 except for 1971-72. The Rangers were also routinely among the top teams in shots prevention. Newly released shot data shows that Giacomin's career shots faced per game rate was 28.8, just 0.3 higher than Ken Dryden's career mark. Giacomin also got a ton of starts, which can be interpreted as either a fortunate opportunity or evidence of his durability, depending on your outlook.

Giacomin did not have much longevity, and he only had about 5-6 peak seasons (which with the single exception of 1966-67 came in the post-expansion period). His career save percentage of .902 exactly matched league average for the seasons he played. He was nothing special once he was shipped out from Broadway to the Red Wings. His playoff record was also decidedly mediocre. The main argument for Giacomin seems to be his award recognition. In addition to being twice named the best goalie as mentioned above, Giacomin was voted the second best goalie at season's end an additional three times. Given that he did not rank in the top 5 in the league in save percentage in any of those three campaigns, despite the advantages mentioned above, it seems reasonable to question whether he truly deserved that recognition.

When evaluating players, I think it is a fair argument to claim that someone with a Hart Trophy or an Art Ross Trophy should have an advantage over a similar player without similar award recognition. With goalies I am hesitant to give the same weighting to individual awards. The two reasons for that is that I believe writers are more likely to get the voting wrong with goalies than with forwards, and that there appears to be more of a luck element involved in a single season's worth of goaltending than for a single season by a forward. Giacomin was repeatedly recognized as one of the game's best, which could have been because he was actually one of the best or it could have been because he was an established goalie playing in a large market on one of the league's best defensive teams that profited greatly from pounding on the league's weak sisters.

As for which goalies were unlucky, I think it is extremely unlikely that Rogie Vachon was a worse goalie than Ed Giacomin. Vachon was much younger when he broke into the NHL and had a longer career, he had a better save percentage (.905) over the seasons that Giacomin also played in the NHL, he played well on more than one team, he had a better Hart Trophy voting record and he represented Canada internationally. I think it's a pretty open-and-shut case, and it makes no sense to me that Giacomin is in the Hall of Fame while Vachon is not.

In a very unbalanced competitive environment, I think it is right to at least question any goalie who only had elite success for a short period of time in a single team environment. It is possible that they had a short peak and then tailed off, but I think the more probable explanation is that they had team advantages during a certain portion of their career that they did not have at other times.

Tuesday, October 12, 2010

The Best Calendar Year Ever?

Recently two different publications, one by Hockey Night in Canada, the other by The Hockey News, have come out with historical goalie rankings. Both of them made what I consider to be a very serious error in underrating Dominik Hasek. I've been beating the drum for Hasek pretty much since day one in this space, not because I am a personal fan of him or any of his teams, but because it is impossible to get deep into goalie statistics without being impressed by the ridiculous level of dominance Hasek displayed in the 1990s.

So here we go again, another chance for me to throw out numbers supporting the great Czech netminder, trying to properly illustrate the unrighteousness of ranking the Dominator as the 5th best goalie of all-time, as THN does, or the 3rd best goalie since 1967 (a la HNIC).

In the calendar year of 1998, including the regular season, playoffs and Olympics, Dominik Hasek had the following stat line: 54-20-14, 1.75, .943, plus 16 shutouts. He averaged nearly 1 shutout every 5 games, playing mostly on a Buffalo Sabres team that was the worst team in the league at shot prevention in 1997-98 and 5th worst in 1998-99. The Sabres' win threshold over those two seasons was .917, meaning that they needed a very good goalie just to be a .500 team. To further stack the deck against the Dominator, the Sabres took more penalties than average in both seasons as well.

The league average save percentage in the regular season was around .906 in that period. In the 1998 playoffs, all goalies other than Hasek combined for an average of .912. Playoff averages usually rise slightly because teams only play their starting goalies. A difference of .006 suggests that the scoring environment was pretty similar between the regular season and playoffs. In the Olympics, the average save percentage was .904 (that's not including Kazakhstan, which got completely shelled in every game).

I'll take .906 as the league average and assume Hasek faced average shot quality, was not impacted by scorer bias and did not play a role in his team's shot prevention (or at least that the effects of all three ended up netting out to zero). Based on those assumptions, Hasek was about 120 goals above average in a 12 month span. Considering he did it in minutes equivalent to 90.3 full games, Hasek averaged 1.33 goals better than average per game for an entire year, during a time period when the average NHL team scored 2.60 goals per game.

That is why Hasek should be talked about among Gretzky, Orr, Lemieux and Howe when people are discussing the greatest peaks in hockey history. It's certainly not conventional wisdom to put Hasek up in the stratosphere with those legends, but there is a numerical case for it. It's possible that, like Hasek, Gretzky had some crazy calendar year that was better than any of his full seasons (maybe 1983, which included most of his ridiculous 51-game point streak), but his most impressive full season may have been 1984-85. Counting regular season, playoffs and the Canada Cup, the Great One scored 95 goals and 172 assists for 267 points and a +126 rating in 106 games.

That stat line probably looks way more impressive than Hasek's to most hockey fans, but a lot of that is probably because we have more intuitive sense about the level forwards produce at than the level goalies produce at. We know that 267 points is far beyond the curve for forwards, but while we realize that .943 is great, we may not have a sense of exactly how great (adjusted for scoring environment, it would be the equivalent of Patrick Roy in the '93 playoffs, or J.S. Giguere in the '03 postseason, for 90 games in a row). Depending on your assumptions about his ice time, the strength of his teammates, Gretzky's defensive ability and the production of an average forward, it's possible to argue that Hasek contributed more on a per-game basis than even the Great One.

For example, let's assume that Gretzky had average ice time, was average defensively and played with average linemates (two of those are clearly false, but bear with me). Since Hasek was being compared to the average goalie, let's use the average first-line forward as the baseline for Gretzky. In 1984-85 the average first-liner, excluding Gretzky himself, averaged 1.09 points per game, which equates to 116 points in 106 games. As a result, we can conclude that Gretzky scored 151 points above average, 1.42 points per game higher than the average forward. That is just slightly better than Hasek's mark even based on the prior assumptions and giving Gretzky sole credit for all of his points. Take into account the fact that he played on the same line as Jari Kurri and the same team as Paul Coffey, factor in Gretzky's heavy ice time, and maybe he doesn't beat the Dominator after all.

That's just a quick-and-dirty method, we could also use a metric that is designed to measure value such as GVT. Gretzky had a 59.1 GVT rating in the regular season and playoffs in 1984-85. Hasek averaged 54.0 GVT in 1997-98 and 1998-99, and added an additional 13.6 in the 1998 playoffs. Including the Olympics and looking just at that calendar year, Hasek probably had a GVT over 70. That means that both in total and on a per-game basis, Hasek's numbers in this period would easily beat not only Gretzky's best season but also the best seasons of Bobby Orr and Mario Lemieux (although, to be fair, GVT typically does rank the top goalies above the top skaters).

Having said all that, Gretzky's peak is extremely impressive because he was able to maintain it for such a long period of time (averaging 203 points per year over a six-season stretch, plus another 31 per year in the playoffs). Hasek was amazing throughout the '90s but I think most would agree that 1998 was his absolute peak, which means that he was probably both playing out of his mind while also having some luck in terms of having the puck hitting him. If you're rating careers then no doubt Gretzky wins, and if you're rating extended primes than there's a good case for the Great One as well. However, for one game, at the absolute height of their respective powers, I'd definitely think twice about it. At the very least I think Hasek down to the next goalie is a bigger gap than Gretzky to Lemieux.

Some people will probably tell you that Gretzky was on a different level than Hasek because the Great One was in a class of his own far ahead of the rest of the league, while Hasek was only just a bit better than Brodeur and Roy. Those people are flat-out wrong. This is what Hasek's main rivals were doing over the same 12 months, see if you think any of them are even close:

Roy: 32-32-6, 2.36, .910, 6 SO
Brodeur: 39-22-11, 2.12, .909, 8 SO
Belfour: 45-18-7, 1.87, .919, 6 SO
Joseph: 41-32-3, 2.38, .914, 9 SO

For an even better expression of the relevant difference, here are the goals against per 30 shots numbers for those four guys and Hasek:

Dominik Hasek: 1.71
Ed Belfour: 2.43
Curtis Joseph: 2.58
Patrick Roy: 2.70
Martin Brodeur: 2.73

Belfour may have been the second-best goalie that year, and he was still dusted by Hasek. Remember that Belfour was playing on the back-to-back President's Trophy-winning Dallas Stars, a terrific defensive team coached by Ken Hitchcock that also took fewer penalties than average. Even if you don't like save percentage or you think that there are other major factors in play like puckhandling, just compare those win/loss records for Belfour on the best team in the league (.875 win threshold) against Hasek on the overmatched Sabres and the underdog Czech Olympic team:

Belfour: 45-18-7, .693
Hasek: 54-20-14, .693

At the very least, I think it's fair to say that the number of players in league history that have had that big of an effect on winning can be counted on one hand.

In my mind it will be a travesty if Hasek is remembered as the third-best goalie of his generation, which is a perception that a lot of media-types are currently doing their best to entrench. In terms of actual performance, the Dominator really does stand alone.

Tuesday, October 5, 2010


Hockey Reference has a metric called the Simple Rating System (SRS) that is designed to measure team strength in terms of predicted goal differential per game. I haven't yet run the complete numbers to see exactly how accurate it is in terms of predicting playoff results, but I do know from hacking around a bit with the results that teams that have a large edge in SRS over their opponents are much more likely to win their playoff matchups.

It appears that the threshold where victory becomes highly likely for the favoured team is when the SRS gap between competing teams is .3 or more. Since SRS claims to be a measure of a team's per-game goal differential above average, that is the equivalent of a difference in goal differential of about +25, which equates to a difference of about 4 wins over 82 games in terms of "true talent" (i.e. the rating is designed to adjust for schedule strength and to remove some of the effects of variance over the course of a single season, such as a team that wins a lot of shootouts or close games).

Even the best goalies in recent times built their playoff records largely on series victories where their team had an SRS rating that was .3 or more ahead of the opposition. Here are playoff series win/loss records for the consensus top 4 goalies of the last two decades split by the strength of their teammates and opponents:

Patrick Roy:
On teams >.3 better than the opposition: 21-2
On teams >.3 worse than the opposition: 2-3
Playoff series against all other opponents: 10-8

Martin Brodeur:
On teams >.3 better than the opposition: 15-2
On teams >.3 worse than the opposition: 0-1
Playoff series against all other opponents: 5-9

Ed Belfour:
On teams >.3 better than the opposition: 12-2
On teams >.3 worse than the opposition: 1-4
Playoff series against all other opposition: 6-6

Dominik Hasek:
On teams >.3 better than the opposition: 5-0
On teams >.3 worse than the opposition: 0-3
Playoff series against all other opposition: 7-4

Combined results:
On teams >.3 better than the opposition: 53-6
On teams >.3 worse than the opposition: 3-11
Playoff series against all other opposition: 28-27

Playing on a much superior team, these goalies combined to win 90% of the time. When playing on a much weaker team, they only managed to win 20% of the time. In all other series it was essentially a coin flip.

It should be noted that the SRS rating is based on regular season performance that includes the contribution of the goaltender themselves. Keep in mind that in some of these situations, the goalie's own play was largely responsible for lifting their team ahead of the opposition. For example, some of the teams had lower win thresholds than their opponents yet higher SRS ratings, which would be an indicator of quality goaltending.

Also, just because the goalie is playing on the better team does not mean they weren't playing well, or were only overseeing 8-0 blowouts. It is important to avoid the common bias in favour of goalies on great teams, but we shouldn't overcompensate by never giving any credit to any goalie with decent teammates. Upsets can easily happen in seven game playoff series. A good team with a good goalie in net becomes tough to beat, as even when the team is off its game the goaltender can sometimes come to its rescue.

As a point of comparison, Chris Osgood was 12-5 in series where his team had a significant advantage. I'm not saying Osgood was to blame for all of those losses, but poor goaltending, or perhaps an average goalie who goes on an unlucky streak, can sometimes sink even a very good team. The high winning percentage in the mismatched series above does seem to indicate strong goaltending, although certainly the rest of the team played a huge role as well.

As an footnote, here are the numbers for Curtis Joseph:
On teams >.3 better than the opposition: 2-3
On teams >.3 worse than the opposition: 2-6
Playoff series against all other opposition: 7-4

In the latter two categories, Joseph's record stacks up against any of the other guys. The main difference was that he did not have nearly as many chances to pound weaker opponents as Roy, Brodeur and Belfour. Cujo was also quite unlucky in terms of goal support, as the Red Wings' failure to score on Giguere in '03 and Kiprusoff in '04 ended up being the main reason for Detroit's downfall in two of his three losses against weaker opposition.

Saturday, October 2, 2010

Some Help from the Official Scorer?

Pekka Rinne, career:
at Home: 42-17-5, 2.21, .924, 29.12 SA/60
on Road: 20-15-4, 2.87, .897, 27.84 SA/60

Those splits certainly make one at least a bit skeptical about whether Rinne's save percentage is being accurately reported in his home rink in the Music City, and whether we can therefore rely on those numbers to accurately reflect his performance. Nashville has been one of the places suspected of a shot recording bias (for more info see Tom Awad or JLikens), which increases the probability that there may be overcounting going on in Rinne's favour.

Unfortunately, this case is not entirely clear cut, because former Predators goalie Dan Ellis doesn't have the same extreme splits. In fact, Ellis actually has a higher career save percentage on the road despite playing all but one game of his career for the same Predators team as Rinne:

Dan Ellis, career:
at Home: 18-16-5, 2.59, .910, 28.82 SA/60
on Road: 32-26-5, 2.68, .913, 30.78 SA/60

Backup goalies can sometimes have skewed numbers because of relief appearances, but even after taking out the 12 games where Ellis came in off the bench, the pattern persists:

at Home: 18-15-4, 2.57, .913, 29.58 SA/60
on Road: 30-22-4, 2.65, .916, 31.62 SA/60

This is a fairly small sample for both Rinne and Ellis, and I expect that some of the effect is simple random variance. It is likely that the .027 difference between Rinne's home and road performance has been a bit of a statistical quirk, as has his good fortune to face almost 4 fewer shots against per game than Dan Ellis while on the road, but I'm still slightly suspicious of the official scorer in Nashville. It will be interesting to see if similar results continue this season with Ellis in Tampa and Rinne expected to once again be the main man in the crease in Nashville.

Wednesday, September 29, 2010

The 1993 Canadiens in OT

Anyone who followed the 1993 NHL playoffs remembers that the Montreal Canadiens had an exceptional record in overtime. The Habs were 10-1 that year in games that went past 60 minutes, and even that one loss tends to get forgotten since it came in the Habs' first playoff game. As a result, the more oft-cited statistic is "Montreal won 10 straight playoff overtime games in 1993".

The journalistic narrative that year was that Patrick Roy singlehandedly won the Cup. Given that Roy didn't score any of Montreal's 10 overtime goals, any reasonable person would have to conclude that there was more to it than that. Roy's contribution was surely significant, but how much of the OT streak was a result of his play, and how much was earned by the shooters in front of him?

The Hockey Summary Project now has the 1993 numbers posted, which means that we now have access to shot data that might help answer that question.

In 11 overtime sessions in 1993 Montreal was outshot 66-59, yet scored 10 goals to their opposition's 1. That's a 16.9% shooting percentage and a .985 save percentage. Needless to say, that is a remarkable run (it is not often you see a PDO number of 1.15, even in a very small sample).

The league average save percentage in overtime in 1993 was .907. Montreal wasn't really affecting that average much since the total save percentage in overtime periods involving the Canadiens was .912, it was just heavily skewed in the Habs' favour.

If they had the league average OT shooting and save percentages Montreal would have been expected to score 5.5 goals and allow 6 in overtime. That means they outperformed their expected goal differential by 9.5 goals, of which 4.5 were the shooters outperforming and 5.0 was the goalie outperforming.

That gives approximately a 50-50 split in total contribution between the goalie and the shooters. Without question St. Patrick was great that spring, but even the best goalies need help if they want to win anything. Contrary to popular myth, Montreal had a very good team in front of him, and the Habs were able to increase their odds by managing to avoid the league's top teams in their playoff bracket. It was still a very heavy dose of good fortune that Montreal was able to be that opportunistic in those high-leverage situations, as without the Canadiens' great record in close games they probably would not have won the Stanley Cup.

Monday, September 27, 2010

What To Expect From: Jimmy Howard

If I had to bet on one starting goalie from last year posting a lower save percentage in 2010-11 than he did in 2009-10, I'd pick Jimmy Howard.

All the signs are there for a regression. First of all, Howard outperformed on special teams. He had a very good save percentage on the penalty kill (.905, 4th among starting goalies), and he faced a low percentage of shots against on the PK to begin with (16.0%). He only let in one shorthanded goal on 50 shots against while Detroit was on the power play. Put all that together, and the result is that Howard's even strength save percentage (.925) was nearly equal to his overall save percentage (.924), something that is rare and generally not sustainable in the long run.

For any goalie with essentially one NHL season under his belt, it's best to look at their minor league performance to see if there is a track record of success. Howard played four full seasons in the AHL from 2005-06 to 2008-09, where he compiled a .911 save percentage on 5,324 shots. That's not bad, but it's nothing that suggests future NHL stardom either. Howard's backups combined for .895 on 4,171 shots, so perhaps there is some evidence that Grand Rapids was not the best defensive team or took a lot of penalties or has a miserly official scorer, but I still don't think Howard's minor league performance is at a sufficient level to foreshadow a future elite NHL starter.

None of Howard's AHL seasons were more than .005 above or below that .911. There's not a clear improvement trend in his numbers, which means that I wouldn't put it at all out of the realm of possibility that he might be a similar goalie in skill level now to what he was the age of 23 or 24. His ascension probably had as much or more to do with spots opening up ahead of him in the organization as with the development in his own game.

It's pretty obvious that the Red Wings themselves didn't think Howard was anything special until very recently. Why else would they have signed Ty Conklin in the summer of 2008 to back up Chris Osgood during the 2008-09 season? Howard was 24 years old with three full seasons in Grand Rapids under his belt at that point, and his own team still didn't rate him as good enough to be an NHL backup. Having said that, the Red Wings are known for their patience in developing prospects, so perhaps it was entirely a matter of maximizing Howard's playing time, but regardless he didn't exactly force his way into the NHL either.

I'm not willing to make the argument that there are strong team effects boosting Howard's performance without a lot more data, but on the other hand I don't rate playing behind Nicklas Lidstrom, Pavel Datsyuk and Henrik Zetterberg to be one of the league's toughest assignments either.

Excluding the 2009-10 regular season, Howard's career NHL record is .912 on 614 shots. That's a tiny sample, but I think it's still probably more representative of Howard's true skill. Puck Prospectus' VUKOTA has Howard projected at a .914 save percentage next year. Guys who have great years are likely to regress somewhat the following year, that's just basic sports statistics. If they don't have an established track record of success either, then the indicator lights are flashing even more strongly. I'd say Howard is more likely to have a below-average save percentage (say, .905-.910) than he is to match his .924 this coming season.

There is of course some small chance that Howard either legitimately became great or his run of luck continues and he remains near the top of the save percentage leaderboard, but it's certainly not the way to bet. It will be interesting to see whether his performance over the next couple of seasons indicates that he is anything special or just another guy at the NHL level.

Thursday, September 23, 2010

What to Expect From Steve Mason

The Columbus Blue Jackets and Steve Mason recently came to an agreement on a two-year extension for the 2011-12 and 2012-13 seasons, at an annual cap hit of $2.9 million.

This deal doesn't make sense to me. First of all, the number seems high relative to Mason's comparables, particularly Carey Price's cap hit of $2.75 million. Secondly, and probably more importantly, I don't think the Blue Jackets really know yet what they have in Mason, who followed his good but overrated 2008-09 season with a pretty weak 2009-10.

Steve Mason's career save percentage in the NHL, regular season and playoffs combined, is .907. That's a below average number in today's scoring environment. I will cut him some slack because he did break into the league at a very young age, and it is entirely possible that he will continue to develop into a goalie with significantly better numbers down the road. But that's why I think this season is pretty important in terms of pegging Mason. It's his third year in the NHL, he's 22, and by all accounts he worked hard on his game over the summer. If I was running the Blue Jackets, I'd tell Mason to prove to me that he deserves to get paid, rather than giving him a sweet deal coming off of a down season. Maybe Mason breaks out and it costs me an extra $500K per season to buy his remaining RFA years, but in the cap era I think it's better to avoid costly mistakes than to pay market value for guys who deserve it.

A lot of people talk about consistency in goaltending, and often it is debatable whether they are actually talking about the variance in the goalie's performance or whether they are simply criticizing or complimenting the goalie's ability. So far in his career, I think it is quite fair to say that Steve Mason has been inconsistent. Kent Wilson at The Score put together an interesting graph of the game-by-game results so far in Mason's career. In 120 career starts, Mason has 15 shutouts and 13 games with an .800 save percentage or worse. That's a shutout percentage of 13% and an awful outing rate of 11%, which are both well above the averages of 6.5% and 7.7% respectively.

I've heard a few explanations given for Mason's results last season. Some questioned his conditioning, others his mental toughness. Teams were shooting high glove on him with great success, which suggests that he needs to work on his technique. Probably a lot of it was simply higher-than-normal random variance resulting from a small sample size. Once again, to me that's a reason to be cautious. If you focus on his shutouts and great games and the way he broke into the league by storm in late 2008, it's probably easy to think that Mason just needs to fix a few things in his game and he is headed for greatness, but that's an overly optimistic viewpoint.

Mason is particularly interesting because he's a guy that has been rated highly by the scouts throughout his career, often perhaps higher than his numbers would suggest he actually deserved. He got drafted in the third round despite not playing very much as a 17-year old in the OHL, he started for the Canadian world junior team ahead of Jonathan Bernier, he was invited to the Team Canada Olympic camp last summer, and he won the Calder and was nominated for the Vezina in 2009. His new contract was mostly based on projection, which again likely relied heavily on input from the team's scouts. Mason is big and moves well, he looks like a butterfly goalie should look, but unless he's actually stopping the puck at a high rate that doesn't translate into helping his team win hockey games.

Columbus is making a bet that they didn't need to make (or at least one they didn't need to make right now), and they likely parted with more money than they needed to, given comparable contracts. I'll be interested to see how it works out for them. I think we'll know a more about Steve Mason after this season, but as of right now I'm not convinced he's an above-average NHL goalie, either now or in the near future. It's a pretty safe bet to expect him to rebound from last year, but I'd still be a bit surprised if he repeated his rookie season mark of .916, especially with Ken Hitchcock no longer behind the bench.

Tuesday, September 21, 2010

Ken Dryden's Backups

One of the great benefits of the Hockey Summary Project has been filling in the gaps in the save percentage record going all the way back to 1952-53. That greatly expands the potential analytical work that can be done on hockey goalies throughout history before the NHL began officially tracking shots and saves in 1983-84.

I got the idea to run the numbers on Montreal backup goalies in the 1970s after following along with the terrific work being done by Black Dog Hates Skunks on the 1972 Summit Series. The scoring chance numbers being compiled there make a pretty good case that Canada was the superior team, but that perhaps the biggest reason the series ended up being close was lackluster goaltending by Ken Dryden.

It shouldn't be too surprising that it would be easier than normal to play goalie on a team that had Larry Robinson, Serge Savard and Guy Lapointe on defence in an unbalanced league further ravaged by player losses to the WHA. The question is how much? Here are the numbers:

Denis Herron:
Montreal: .901 on 2178 SA
Elsewhere: .889 on 9412 SA

Phil Myre:
Montreal: .904 on 1432 SA
Elsewhere: .881 on 11317 SA

Rogie Vachon:
Montreal: .912 on 5391 SA
Elsewhere: .890 on 16221 SA

Michel Plasse:
Montreal: .888 on 866 SA
Elsewhere: .880 on 8015 SA

Wayne Thomas:
Montreal: .906 on 1424 SA
Elsewhere: .886 on 5563 SA

Bunny Larocque:
Montreal: .894 on 5860 SA
Elsewhere: .861 on 1829 SA

Average save percentage for Dryden backups in Montreal: .902
Average save percentage for Dryden backups elsewhere: .885

I don't think anybody should be surprised by the confirmation that being the Habs' netminder in the 1970s was a pretty sweet gig.

That second number is actually even lower if you weight the other goalies' save percentages based on how much they played in Montreal, although Larocque's numbers have a big effect there since he makes up such a large part of the sample and has a comparatively low amount of playing time outside Montreal.

It's possible that the difference between some of these goalies is somewhat exaggerated as they would have been more likely to face expansion teams as a backup in Montreal and more likely to face the league's best teams (including the Canadiens themselves) as a starter in Pittsburgh or Kansas City or wherever else they played. It's not always an apples-to-apples comparison either because some of these guys were on their way up or their way down when they went through Montreal. Still it's a six goalie sample that supports what we already know: that the Canadiens had such a strong defence. On top of that, the Habs also did not take many penalties, which would be a further benefit for the team's goalies.

If we adjust Dryden's numbers based on the above difference, his career .921 becomes .907. That remains a very good number, given that the league average over that period was .893, but that certainly puts Dryden in the conversation with Tony Esposito (.912 over the same stretch) and Bernie Parent (.914 in the same seasons on a much more heavily penalized team) for the title of the best goalie of the 1970s.

Thursday, September 16, 2010

The Era of Bargain Goalies

After the past offseason, I feel like I should be changing my handle to The Not-Quite-So-Contrarian Goaltender. A number of NHL teams came around to what stat guys have been preaching for a while now, that you shouldn't commit big bucks to the position because there is little margin in goaltending these days and the supply of decent goalies currently exceeds the demand.

Given the economic realities and the nature of the game at the moment, it is simply the smart team-building move to avoid committing big cash to any goalie that hasn't already demonstrated beyond reasonable doubt that he is a difference-maker. That's not great news for the financial plans of goaltenders or prospects aspiring to make the NHL one day (perhaps leading to a lot more Dan Ellis Problems), but that's just the way it is. That message is spreading around the league, from the Hawks walking away from Antti Niemi to the Sharks cutting ties with Evgeni Nabokov to the Canadiens choosing to trade rather than pay their playoff hero Jaroslav Halak.

I've seen some dismiss this as merely the typical rush to copycat the most recent Stanley Cup winner, but I'd certainly dispute that argument. The signs of a goalie glut have been there for a while now, and it's been 7 seasons since a team won a Cup with a Hall of Fame goalie. The five starting goalies with championship rings since 2006 have an average post-lockout save percentage of .906. The league average over that period has been .907.

Average goaltending is good enough these days for a team that has quality in the rest of their roster. Given that, it's not at all surprising that the market price of goalies has been dropping in the salary cap era. The blueprint for many teams is to invest in the guys up front to try to assemble a lineup that can outchance the opposition. That alone should be enough to get into the playoffs and maybe even win a round or two against a weaker opponent, and from that point it's just a matter of crossing their fingers and hoping to get the hot goaltending and/or shooting luck needed to get their hands on the Cup.

I've been busy over the summer working on the Hockey Prospectus annual and other projects, but should be back on a regular posting schedule with training camps starting up around the league.

Thursday, June 24, 2010

Goals Against Per 30 Shots

I'm always looking out for different ways to express goalie performance, and ran across an interesting one that I'd never seen before while going through the archives at Tom Tango's Inside the Book blog. He wrote a brief Wall Street Journal article that expressed goals against average in terms of goals against per 30 shots, rather than goals against per 60 minutes of play. That gives a metric that is pretty much just a translation of save percentage (GA/30 = (1 - Sv%) * 30), but the advantage is that it results in figures that look like goals against averages. GAAs are more familiar and intuitive for most people to understand than save percentages, and allow a better sense of the actual difference between goalie performance on a per-game basis.

There is one slight tweak I would suggest to Tango's number, and that is to adjust for special teams. I'd suggest calculating even strength goals against per 24 shots and goals against per 6 shots on the penalty kill, which reflects the typical 80/20 split between non-PK and PK shots, and then adding those two numbers together to get a special teams adjusted goals against per 30 shots number.

Here are the league's top 20 goalies last season based on this metric (min. 35 starts):

1. Tuukka Rask, Boston: 2.17
2. Ryan Miller, Buffalo: 2.21
3. Jaroslav Halak, Montreal: 2.26
4. Evgeni Nabokov, San Jose: 2.34
5. Tomas Vokoun, Florida: 2.36
5. Ilya Bryzgalov, Phoenix: 2.36
7. Jimmy Howard, Detroit: 2.37
8. Henrik Lundqvist, N.Y. Rangers: 2.41
9. Jonas Hiller, Anaheim: 2.44
10. Miikka Kiprusoff, Calgary: 2.45
11. Craig Anderson, Colorado: 2.50
12. Cam Ward, Carolina: 2.53
13. Tim Thomas, Boston: 2.57
14. Chris Mason, St. Louis: 2.60
15. Johan Hedberg, Atlanta: 2.61
16. Martin Brodeur, New Jersey: 2.63
17. Roberto Luongo, Vancouver: 2.64
18. Marty Turco, Dallas: 2.65
19. Antti Niemi, Chicago: 2.67
20. Jose Theodore, Washington: 2.68

I think by the majority of measures Miller was a deserving Vezina winner and First Team All-Star, so kudos to the voters this year for getting it right.

Monday, June 7, 2010

Shot Recording in the NHL

Shot recording bias is a topic that I have always wanted to look at but haven't yet got around to, until my latest article over at Puck Prospectus. I think it is something that has a real impact on goalies around the league and that we need to avoid rating goalies based on rink effects.

I use the zone time metric in my analysis, which unfortunately limits me to a three year period almost a decade ago. It would have been nice to have a larger sample size, and to try to look at shot effects in today's NHL, but alas the NHL decided to discontinue tracking zone time after the 2001-02 season.

Thursday, May 27, 2010

Special Teams Play: Luck or Skill?

There is a Vezina Trophy winner hidden in the following table of even strength save percentage leaders from one of the seasons in the last decade. See if you can spot him:

1. Goalie A, .934
2. Goalie B, .931
3. Goalie C, .930
4. Goalie D, .929
5. Goalie E, .929
6. Goalie F, .929
7. Goalie G, .925

Obviously it's not the guy at the top of the list, because that would be too easy and I wouldn't be asking the question in the first place. It's not the guy at the bottom of the list either, I only included him because he is a future Hall of Famer. That leaves the goalies in slots 2 through 6, who have nearly identical save percentages. None of these goalies are backups who got lucky for a few months, they are all their team's clear #1 starter. Goalie E played in 53 games while the rest played between 58 and 67.

Let's add in their save percentages on special teams, and the % of the shots faced that came on special teams:

1. Goalie A: .934 EV, .897 ST, 22.6% on ST
2. Goalie B: .931 EV, .931 ST, 18.5% on ST
3. Goalie C: .930 EV, .889 ST, 23.6% on ST
4. Goalie D: .929 EV, .882 ST, 23.8% on ST
5. Goalie E: .929 EV, .888 ST, 20.6% on ST
6. Goalie F: .929 EV, .877 ST, 25.0% on ST
7. Goalie G: .925 EV, .884 ST, 23.5% on ST

Now I think it's pretty obvious who won the Vezina. Not only that, but he also won the Hart Trophy. Goalie B is Jose Theodore, and the year is 2001-02. The other goalies, in order, are Patrick Roy, Sean Burke, Evgeni Nabokov, J.S. Giguere, Roberto Luongo and Dominik Hasek.

Did Theodore deserve his awards that year? That all depends on how you assess his special teams performance, whether you consider it to be a result of his skill or whether it was mostly luck or random chance or the play of his team's PK unit. You can make the argument that Theodore was the most valuable goalie that year because he faced many more shots against than any of the other goalies behind Montreal's porous defence, but there's not too much evidence to suggest that he was better at even strength than the other goalies who had almost identical rates.

I think Theodore had a career year in 2001-02, but that he still was pretty fortunate on special teams. It's possible that Theodore played better in certain game situations than other goalies and therefore was actually the best that year, but I'm not entirely convinced. The other goalies listed above almost all have much better track records than Theodore. I wouldn't say that Theodore's season was one of the weaker Vezina-winning seasons, as finishing second in EV SV% is still an impressive result, but I would say it is the most "smoke and mirrors" .930+ save percentage season that I am aware of.

In fact, I'm pretty sure that early-career Jose Theodore must have been among the luckiest special teams goalies in league history. In Theodore's first four seasons he stopped 89.3% of the shots he faced on the penalty kill. Since then, his PK SV% has dipped to a mere .850.

That might be attributable at least in part to a decline in Theodore's performance or the play of the team in front of him, but his performance on the power play was luckier still. In his first five seasons in the NHL, Jose Theodore stopped 321 out of 333 shots against while his team had the man advantage. That's a .964 save percentage in a situation where the league average was .917. In the year of his Vezina glory in 2001-02, Theodore peaked with a perfect 69-for-69 on power plays.

This year's Vezina is also likely going to be won by a special teams overachiever. Here are the numbers for this year's Vezina nominees:

Ryan Miller: .928 EV, .929 ST, 19.4% ST
Ilya Bryzgalov: .927 EV, .896 ST, 22.0% ST
Martin Brodeur: .924 EV, .873 ST, 15.7% ST

Here are the same statistics for several other goalies, all of whom had EV SV% equal to or better than Miller in 2009-10:

Tomas Vokoun: .937 EV, .873 ST, 19.2% ST
Tuukka Rask: .937 EV, .906 ST, 19.1% ST
Jaroslav Halak: .933 EV, .885 ST, 18.8% ST
Jonas Hiller: .930 EV, .874 ST, 20.5% ST
Henrik Lundqvist: .929 EV, .886 ST, 18.7% ST
Evgeni Nabokov: .928 EV, .900 ST, 22.1% ST
Miikka Kiprusoff: .928 EV, .888 ST, 21.0% ST

I think it was actually a pretty tight race for the top goalie this season, which is interesting since Miller has probably had the Vezina wrapped up since Christmas. I'm very interested to see how Miller does next season. I think it's a pretty safe bet to expect a great deal of regression to the mean in his special teams totals. I'm not saying he's a Jose Theodore, but I'm also not anointing him the best goalie in the world yet either.

This is not to say that special teams play is pure randomness. It can sometimes seem that way over a short sample, for example a playoff series or two, but PK save percentages generally correlate with 5 on 5 save percentages over multi-year samples. The problem is that typically only 1 in 5 shots come on the penalty kill, which means that evaluating a goalie based on single-season penalty kill performance is roughly the equivalent of evaluating a goalie's overall performance based on 12-15 games. As these playoffs have shown, anybody can run hot or cold over a short stretch like that.

In the long run goalies should be rewarded for persistently strong performance on the penalty kill, but results should be viewed skeptically over a single season. We don't want to be awarding the Vezina every year to the goalie who was the luckiest on the penalty kill, but we also should give some credit to a goalie who was excellent while his team was shorthanded. That makes it difficult for analysis.

Wednesday, May 19, 2010


Here are the best and worst 14-game save percentage streaks during the 2009-10 regular season for each of remaining final four teams:

Philadelphia: .936 and .870
Montreal: .943 and .882
Chicago: .937 and .874
San Jose: .944 and .887

And the same thing for seven game series:

Philadelphia: .946 and .857
Montreal: .952 and .871
Chicago: .955 and .844
San Jose: .967 and .853

The similarity in range illustrates again how the margins are very small in goaltending. Over a short sample the skill element of goaltending can be completely lost in the noise of whether the opposing shooters are missing, the puck is hitting him through screens and traffic, or whether he happens to be in peak form or not. Most teams will have at least one streak of seven games or more where their team save percentage is .940 or better, yet analysts are repeatedly stunned when some lesser goalie hits that mark or a star goalie sees his numbers dive to sub-.900 levels over the course of a playoff series.

With the Canadiens' shooting and save percentages taking a clobbering in back-to-back shutout losses to the Flyers, I think we have a new leader in the clubhouse for the luckiest team in the playoffs. With an 11.8% shooting percentage and a .933 save percentage Philadelphia is absolutely rocking the percentages. Take a look at the PDO numbers (shooting percentage plus save percentage) for the teams that are left:

Philadelphia: 105.1
Chicago: 102.2
Montreal: 101.2
San Jose: 98.5

The only way the Flyers can likely compete with the Western champ is if the pucks keep going in and staying out at ridiculous rates. If Michael Leighton can keep his even-strength save percentage in the .980 range then that should probably do it, but unfortunately the winds of chance tend to be fickle, as the Canadiens are finding out. We don't know how the bounces are going to shake out for the rest of the playoffs, but it's probably fair to say that barring some ridiculous streak occurring everything looks lined up for the end of a long Cup drought in Chicago.

Friday, May 14, 2010

Shot Quality and the Montreal Canadiens

I fooled around with tracking shot quality in last year's playoffs, using shot charts to try to get a sense of where teams were shooting from. One of the most interesting sets of numbers that I happened across was at CBS Sportsline, where they track where a shot was targeted on goal (e.g. low glove, low blocker, five-hole, high glove or high blocker).

This data showed that high shots were much more likely to go in than low shots. The problem was that it was very unevenly done. Some games had no high shots recorded at all, others had just a few, while others seemed like they had a more reasonable number. I ended up just filing it away as something to potentially check on if I was trying to assess the shot quality of a particular team or series of games.

A lot of people are trying to explain why the Montreal Canadiens are having so much success this postseason, and one of the factors they typically point to is that the team is forcing their opponents to shoot from the outside. Often people talk about shot quality when they want to try to justify why one team is running hot with the percentages. In the long run teams tend to converge to the average. However, I think it is entirely possible that shot quality could be a factor when one team is playing against a single opponent over the course of a playoff series.

I thought to look at the high/low CBS numbers for Montreal's series against both Pittsburgh and Washington to see what they tell us. If Montreal's skaters are legitimately doing something to impact the other team's shots, then we would expect to see their opponents have a higher percentage of low shots than the Habs. If this is a bunch of talking head garbage, then the percentages are going to be similar for both teams and Montreal was just lucking out.

What do the data tell us?

Montreal vs. Pittsburgh:

High shots: Pittsburgh 45, Montreal 45
Low shots: Pittsburgh 180, Montreal 128

Montreal vs. Washington:

High shots: Washington 73, Montreal 62
Low shots: Washington 216, Montreal 131

Wow. I'd say that at least warrants a closer look.

It's important to note that we have to be careful with this data. It still seems like whoever tracks this stuff sometimes just falls asleep for a period here and an entire game there. For example, in game one of the Pittsburgh series just 2 out of 55 shots were recorded as being high, and in game three against Washington just 3 of 77 shots were marked down as high shots. Several other games were suspect (games 6 and 7 against Washington, games 3 and 5 against Pittsburgh), all of whom had a total of 8 high shots or fewer for both teams.

I'm inclined to throw those games out, and rerun the results.

Montreal vs. Pittsburgh (G2, G4, G6, G7 only):

High shots: Pittsburgh 37, Montreal 39
Low shots: Pittsburgh 116, Montreal 53

Montreal vs. Washington (G1, G2, G3, G5 only):

High shots: Washington 60, Montreal 56
Low shots: Washington 98, Montreal 61

Montreal won 6 out of these 8 games, so these games may not be exactly representative of the two series. However, it is a good sample to try to figure out whether the Habs' defensive tactics were effective. This evidence certainly suggests that they might have been, assuming that this data is good. Whether it was because they had more pressure on the puck, or because they were clogging the shooting lanes, or because they had more counterattack opportunities or odd-man rushes, these numbers are evidence that Montreal's shots may have been of higher quality than those of their opposition, particularly against the Penguins.

Even if that was true, that of course does not mean there was no luck involved. The Habs have benefitted from a healthy dose of good fortune, especially against the Caps. Today's goalies are very good at taking away the bottom of the net, but low shots aren't by any means harmless, especially ones taken close to the net. Think of Halak's pad save on Evgeni Malkin in the third period of game 7, for example. The Habs have survived a bunch of similar chances in the playoffs.

Montreal is not likely to sustain either their shooting percentage or save percentage numbers so far (13.7% on high shots and 10.5% on low shots in the second sample, compared to 9.3% and 6.1% respectively for their opponents). I'd say they should still be the underdog in the Eastern Conference Finals against whoever wins tonight. Yet maybe there is at least something to Jacques Martin's madness after all.

Wednesday, May 12, 2010

The Age of Goalie Parity

Here are the post-lockout playoff win/loss records of the top 10 goalies in post-lockout regular season save percentage (minimum 200 regular season games played):

Tomas Vokoun: 1-4
Niklas Backstrom: 3-8
Henrik Lundqvist: 14-16
Tim Thomas: 10-8
Martin Brodeur: 15-22
Roberto Luongo: 17-17
Ryan Miller: 22-18
Ilya Bryzgalov: 12-9
Cristobal Huet: 6-11
Miikka Kiprusoff: 9-16

Combined record: 109-129

That's pretty remarkable, the teams with the top-performing goalies on them have been more likely to lose than to win in the playoffs. And that list certainly makes one wonder why Roberto Luongo seems to take more heat for his playoff team success than the rest of the guys combined, even though only three of them have better win/loss records than he does.

As we all know, factors other than goalie skill contribute heavily to determining the winner, but it's also true that the top performers in a population with a small standard deviation in skill (like NHL goalies) will not have much of an advantage over a relatively small sample size of games (like the NHL playoffs). It's quite possible that the worse goalie outperforms the better goalie in a playoff series, and indeed we've seen it happen several times these playoffs. After all, a difference of .005 in save percentage is just 1 goal every 200 shots, which is a typical number of shots a goalie might face in a seven game series. Niemi outplaying Luongo or Boucher outplaying Brodeur is going to happen a lot more often than most people think.

In today's NHL offence wins championships and pretty much all the goalies in the playoffs are decent. The best goaltenders have not been winning championships and it's not going to happen this year either. Sometimes it really is better to be lucky than to be good.