Monday, December 7, 2009

Why Offence Rules the New NHL

"Defence wins championships" is a familiar cliche that is thrown around as a truth in not only hockey circles, but by fans of virtually every team sport. At some points in hockey history it may have been true, but I believe the game has changed. In the new NHL, the evidence suggests that offence wins championships.

First of all, I'll give the small sample size warning to everything that I'm about to post. Past results do not guarantee future performance and so on. I tend to believe the numbers show a real effect since regular season results have generally fallen in line, but I'm going to be focusing on playoff results only which means that the sample is limited to 60 playoff series over the last 4 seasons.

Secondly, I'm ignoring all shootouts here. Goals for and goals against mean actual goals, not the goal awarded in the standings to the team that won the shootout. I counted all games that went into a shootout as ties for both teams, so because of that a few times I considered a team that finished lower in the standings to have had a better record than their opponent. This approach makes sense to me since shootouts don't happen in the playoffs.

It is important to realize that in the playoffs nothing happens with a high degree of certainty. Upsets regularly happen in short series. Just to establish a baseline, over the period from 1955-2009 the team with the better regular season winning percentage has won 65% of the playoff series. Since the lockout the percentage has fallen to 61%, which likely reflects the higher level of parity in today's game.

If the better overall team wins 61% of the time, how does the better offensive team do? Answer: The team with more goals scored has actually done even better, winning 37 of the last 60 series (62%). That's a much better success rate than the team with fewer goals allowed, which has won just 27 series (45%).

Often the same team will be better in both categories. For example, the 2008 Detroit Red Wings had better regular season offensive and defensive numbers than all four of their playoff opponents. Let's look only at series when a team with more goals scored plays against a team with fewer goals against, the classic offensive team vs. defensive team scenario. In those matchups, the stronger offensive team has won 24 out of 38 times (63%).

The numbers also show the value of looking at a team's win threshold. The team with the better win threshold won 38 out of 60 series (63%). Win threshold has been a better predictor of success since 2006 than a team's overall record or number of goals scored. As you can infer from that result, a team with a higher win threshold was slightly more likely to win than an opponent with a lower win threshold even when the latter had a better win/loss record, although this advantage was slight (11/21, 52%).

When we focus on goaltending, we also see that the post-lockout playoffs have been determined primarily by the play of skaters, rather than by the play of the masked men. The team with the better regular season save percentage has won just 25 out of 60 series (42%). When a team with a better save percentage has played against a team with a better record, the team with the better goaltending won just 7 out of 25 series.

If you look at each position individually then goalie is the most important position in hockey, but the 18 skaters as a group are collectively much more important than the goalie. A good measure of the effectiveness of the skaters is a team's win threshold. Since the lockout, when a team with a better win threshold went up against a team with a better save percentage, the team with the better skaters won 26 out of 39 times (67%). Given the uncertainty of playoff results in hockey, that is a very high probability.

There is another cliche that goes something like, "In the playoffs you don't need a great goalie, you just need a hot goalie". If you have a dominant team then you might not even need that, but for most teams that is probably not far from the truth. The abundance of good goalies in today's NHL means that a lot of teams have a goalie that is capable of excellent play for a month or two. The best goalies are not able to be the difference makers that they perhaps once were, and that means that goaltending ranks well behind a team's offensive ability in terms of predicting their success.

17 comments:

Triumph said...

great work, as always.

i'm convinced that offense is the future of the NHL; that edges that were once large on defense/goaltending are closing due to better instruction at lower levels, and that success really comes down to puck possession/scoring.

Agent Orange said...

CG in your study was there any obvious advantage for which teams made the playoffs in those years?

The numbers indicate a better offensive team will win a playoff series but who is more likely to get into the playoffs?

If the top 16 defensive teams are the ones making the playoffs (unlikely I know) does that really agree with offense leading the charge in the NHL?

Wouldn't a better metric to look at me GF/GA (ratio) in the regular season? Comparing offense ranking to defense ranking is deceptive. If a team that is Offense/Defense 1/2 plays a team that is O/D 30/1 you would of course expect the first team to win. But you would expect them to win because of their balance not just because of the strength of their offense.

With 4 years of rounds to look at I expect this might happen a high % of the time because you have 32/60 being first round match-ups. Usually a good team against a not so good team.

Just my 2 cents.

Bruce said...

The numbers indicate a better offensive team will win a playoff series but who is more likely to get into the playoffs?

Great question, Agent Orange. As I see it the regular season is stacked to reward the defensive minded clubs, as merely getting to overtime is a successful night's work, and the dice roll of 4v4 OT and the shootout makes the average regulation tie worth 1.5 points. So if the score is tied in the third, playing to win is actually a loser strategy and protecting the tie is the name of the game. Indeed, from a probabilistic perspective a game-tying goal has three times the value of a game-winning goal! So if a game is already tied that has value to both teams. Such has competition been compromised in Gary Bettman's NHL.

I did a detailed study after the 2007-08 season in which I destermined that the top 15 defensive teams in the NHL all made the playoffs!!! Don't think it's been quite that extreme before or since, but a good defensive posture is the first plank of artificial parity.

Once in the playoffs of course, getting the game to OT is worthless, you have to be able to actually score to win. And you better be able to score 5v5.

The difference between regular season and playoff hockey is like the difference between driving a an automatic and a standard: one goes til you make it stop, and one stays stopped 'til you make it go.

Lawrence said...

This was linked elsewhere, and these were my comments, maybe I am out to lunch, but I think it's a valid point. Forgive me for the ctrl+c

So, I don’t have time to go through all of the stats, but the idea in my mind of “Defense wins championships” doesn’t mean a defensive team with no offense will win the Cup or series, it means that a team that goes far will usually tighten up defensively. In other words “any team needs to focus on being better defensively in the playoffs than in the regular season to win a championship.”

For example:

Pittsburgh won the cup. Reg season GF 3.22 GA 2.91 vs Finals GF 2.00 GA 2.43
Detroit lost the cup. Reg season GF 3.60 GA 2.98 vs Finals GF 2.43 GA 2.00

Fleury Reg – .912, 29.8sa vs PO – .908, 28.6sa
Osgood Reg. – .887 26.2sa vs PO – .926, 27.7sa

Had Detroit kept the SA totals matching the Reg season, they likely win the cup.
Had Pittsburgh allowed as many SA in PO as in Reg, Detroit likely wins the cup.
Detroit already outscored Pittsburgh but still lost.
Notice the drop in scoring across the board.

This is obviously just one series, but we know that in playoffs scoring is down per game and shot totals are lower. I think that’s where the expression originates from.

I think of it as “We achieved X tier to advance, playing the way we have, now we need to be better defensively to win the cup, because there is less margin for error.”

not

“We are playing a stronger defensive team….we will likely lose, because everyone knows that defensive teams win the cup.”

As well, we’re only thinking of the NHL paradigm. There are also Olympic championships, World Cup, World Championships etc.

In a single game elimination scenario, I am going to want a team that can dominate a margin on low shot totals vs the same margin on high shot totals. IE. I want Canada to play 25F-15A shot games vs 45F-35A shot games, because of the odds.

The Contrarian Goaltender said...

I looked up the average rank of playoff teams in their own conference for each of the past 4 seasons:

Eastern Conference:

2005-06: 5.9 GF, 4.9 GA
2006-07: 6.1 GF, 4.9 GA
2007-08: 7.5 GF, 5.1 GA
2008-09: 6.4 GF, 6.0 GA

Western Conference:

2005-06: 5.4 GF, 5.4 GA
2006-07: 5.8 GF, 4.5 GA
2007-08: 7.1 GF, 5.4 GA
2008-09: 4.9 GF, 6.3 GA

There has been a consistent edge for the defensive teams in the Eastern Conference. In the West it has been closer, and last year the scales were tipped in favour of offence.

If you have an elite offensive team you are very likely to make the playoffs, but if you are a team on the fringe with an above average offence and below average defence, then yes it is quite possible that someone else's loser points knock you out of the postseason.

The Contrarian Goaltender said...

Lawrence: I'm confused as to how you think Canada has better odds in a 25-15 shot game than in a 45-35 shot game. Shouldn't we expect Canada's shooters and goaltenders to be better than the opposition? And if so, wouldn't it make sense to increase the sample size to reduce the luck effect and increase the skill effect?

Just like the underdog team in football has a better chance if they run the ball, keep the clock moving and limit the number of possessions for each team, playing a low-event game is an equalizing factor, rather than an advantage for a powerhouse team.

nightfly said...

Bruce - excellent article. I will be linking it the next time I do my "Real NHL Standings" on Monday.

Taylor said...

This reminds me of why a baseball position player's value is more in their hitting than their fielding. Their is a bigger difference between players in hitting than in fielding. Most batted balls are either hits or outs regardless of who is playing the field. Whether its the type of batted ball that is almost always a hit or the type that is almost always an out is due to the batter's skill and random chance. Random chance evens out. The situation with scoring chances in NHL hockey seems very similar. The majority of goals will be goals no matter who is in the net and the majority of saves will be saves no matter who is in the net (of course this is true because the worst goalies save about 88%). I think you need to compare the expected goals of teams (based on shots/gm and shooting %) and get a feel for how much they differ from team to team. Then compare that to how much save %'s actually differ. I think you'll find that the goalie can't usually compensate for the teams offensive inferiority because the difference between the good goalies and the poor goalies is not as great as the difference between the good offenses and the bad. I hope this makes sense. (I'm not sure myself)

Anonymous said...

You need to update your most overrated goalie list. Nabakov has definitely been surpassed by Henrik Lundqvist.

Lawrence said...

CG: Nope...not at all. I don't think Canada's scorers are better than any of the Elite European team, based on skill, save maybe Finland. Certainly not Russia, Sweden and maybe even with the Czech Republic. They will out skill us any day of the week. We have small ice and should be able to put a physical game to better use. Goaltenders are a game by game matter. I agree that the luck effect can be devastating in a 25-15 game, but there aren't many chances for it with 15 shots against are there? I think the best chance Canada has to win is to keep the SA as low as possible.

Goaltending internationally is a draw in my mind.

Vokoun vs Kiprusoff vs Lundqvist vs Brodeur vs Miller vs Nabby/Bryzgalov. ??? It's a pretty even hand.

Bruce said...

I think the best chance Canada has to win is to keep the SA as low as possible.

Sounds like Brodeur to me.

Bruce said...

You need to update your most overrated goalie list.

I'll say. Nabokov continues to get the job done in San Jose, posting a 103-38-22 record since the start of 2007-08. I know you hate that stat, CG, but a Pts% of .699 is getting the job done, I don't care how good your team is.

Backups have a combined .621, btw; there's no doubt the Sharks are good. But Nabokov is part of the reason they're as good as they are.

I had a chance to see Nabokov in a live game a couple of weeks ago, the night Sharks beat the Oilers 5-4 in a shootout. He had a bit of a rough third period when the Oilers really executed on their opportunities, but I left the game being more impressed with him than I expected. He's real sharp on the puckhandling/game management side of things, very active and involved.

***

You also need to update your most underrated list while you're at it. I have Kari Lehtonen rated as a talented but injury-prone prima donna, and there's not much happening to change that opinion, especially the injury-prone part. The Thrashers are thriving in his absence, which I realize goes partly to other factors but it's not like their goaltending fell off a cliff either.

If anything, that guy has been OVERrated since his draft year. Lots o' hype, flashes of delivery but a lot of disappointment along the way, and he is nowhere close to covering his #2 overall bet. Injuries a big part for sure.

My own vote might go to a guy who's a long way under the radar but really delivering the goods, namely Ilya Bryzgalov.

Such designations as "underrated" are suspect in that they are in effect two opinions, one's own compared to another, perceived consensus. (e.g. Lehtonen/Bryzgalov/Vokoun/Smith/Turco/Whoever doesn't get enough credit/isn't well known) Moreover, if one starts from a simplistic assumption of that consensus -- such as, say, "In hockey, goalies get all the credit" :) -- then one is buiding one's own opinion, however well supported, on a shaky foundation.

Anonymous said...

"..a Pts% of .699 is getting the job done, I don't care how good your team is. "

An excellent goalie would have a pts% of .750 with that team.

The Contrarian Goaltender said...

Good points made on the overrated/underrated. I haven't updated that in a while, and the problem with judging something as overrated or underrated is that how they are "rated" changes constantly. I decided to just take that whole section out.

My justification for calling Lehtonen underrated was that he tended to have the largest gap between subjective ratings (e.g. THN polls) and various statistical metrics. I'd say on a per-game basis his performance suggests he is better than most fans/media think, but of course his overall contribution to his team is obviously much lower than it would have been if he was able to stay healthy.

Agent Orange said...

"Eastern Conference:

2005-06: 5.9 GF, 4.9 GA
2006-07: 6.1 GF, 4.9 GA
2007-08: 7.5 GF, 5.1 GA
2008-09: 6.4 GF, 6.0 GA

Western Conference:

2005-06: 5.4 GF, 5.4 GA
2006-07: 5.8 GF, 4.5 GA
2007-08: 7.1 GF, 5.4 GA
2008-09: 4.9 GF, 6.3 GA"

Maybe I read this wrong but these numbers tell me that you are more likely to make the playoffs as a top defensive team than a top offensive team. Am I correct?

I think the reason for the offensive advantage in the playoffs is likely because all the teams are good defensively (the top half of the league). As a result a team with a decided offensive advantage has something that tips the scales in their favor.

In addition to that teams with a lot of balance (like the 2008 Red Wings) have a very high likelihood of winning the Cup.

denis pelletier said...

Offence is now of capital importance, no doubt about it. But I'm not ready to say that superlative goaltending can't make THE difference. For example, I think that it is making THE difference in Buffalo at the moment. The question, of course, is will the lack of scoring catch up with them later in the season.

I guess one current example of your position is the Canadien atb the moment. Price may be posting a very respectable 1.87 over the last 16 games, but the CH hasn't been winning as much as that figure would lead you to believe... because of lack of offence.

So maybe Buffalo is just an exception.

The Contrarian Goaltender said...

Agent Orange: That's correct, playoff teams tend to rank slightly higher defensively than offensively. I think that an all-out defensive team is likely to do better than an all-out defensive team. However, I agree that in an environment where all teams are solid defensively, offence becomes the difference-maker. That's what we have seen in the playoffs, and I think that's what we've seen in the regular season as well in the Western Conference over the last couple of seasons.