pmyrland

Why Alex Ovechkin Is Not The Best Goal Scorer Ever

Having pointed out the problems with Hockey-Reference’s adjusted points formula and made the case for an improved version of adjusted scoring, it’s time to look at the question of where Alex Ovechkin should rank on the all-time list of goal scorers. As my title already gives away, when the era biases in the adjusted metrics are corrected, it turns out that Ovechkin’s numbers, while unquestionably outstanding, are no longer the best.

That on its own does not necessarily mean that Ovechkin isn’t #1. All scoring stats, adjusted or not, should be viewed in context, with understanding of a player’s usage, role and team situation. Ovechkin also has plenty of years ahead of him, and there is a reasonable case to be made that relative dominance is more difficult in the current era. I’ll show here why I think others are more deserving of the greatest of all-time mantle based on my adjusted goal calculations, but opinions can certainly differ. At the very least though, I hope that in the future any claims of Ovechkin being history’s greatest will be supported by more compelling evidence than links to Hockey-Reference adjusted goal totals. Continue reading “Why Alex Ovechkin Is Not The Best Goal Scorer Ever”

The Problem With Hockey-Reference’s Adjusted Scoring

Hockey-Reference is a great resource for historical NHL data and quick summary statistics for players. The Play Index and detailed player splits are very useful, and the site has also added the kind of summary stats (particularly scoring and save percentage broken down by special teams) that once upon a time I used to go to NHL.com for before SAP ruined its usability.

One thing Hockey-Reference has not been as successful with is developing other stats, like player value metrics. Most people rightly see things like Point Shares and Goals Created as not adding a lot of value. However, one stat frequently cited and largely taken at face value within the analytics community is Adjusted Points (or Adjusted Goals, depending on what type of player is being talked about). I am certainly no exception, having made a case based on adjusted scoring in my last post.

I have heard it claimed that adjusted scoring was biased towards or against certain eras, but hadn’t ever looked at it myself in much detail until a number of articles started popping up suggesting that Alex Ovechkin might be the greatest goal scorer of all-time. Some of the exact same arguments have now been flaring up again in the wake of Ovechkin scoring his 500th career goal this past weekend.

What I found particularly interesting was that the cases being made were very heavily based on adjusted scoring. If there was indeed some statistical bias impacting that metric, it would likely affect any conclusions being made about Ovechkin’s potential GOAT scoring status, as well as any other cases made for or against other players based on their adjusted numbers. In this post, I’m going to outline the problems with the Hockey-Reference version of adjusted scoring, and then propose an alternate method. In a future post, I’ll look at how my method stacks up in terms of evaluating historical players. Continue reading “The Problem With Hockey-Reference’s Adjusted Scoring”

Why History Suggests Carey Price Deserved the Hart Trophy

I’m generally a fan of the Washington Post’s Neil Greenberg, but in the wake of Carey Price sweeping the NHL awards last night I feel obligated to respond to an argument that he has championed this season. It’s been expressed in a few different ways (and by other people as well, of course), but generally has come down to some version of the claim that since goalies have rarely won the Hart Trophy historically, Alex Ovechkin should have been the expected and possibly more deserving Hart winner.

To quote Greenberg from yesterday:

“But would the voters name Price as the league’s most valuable player over Ovechkin? History shows they haven’t in the past.”

Obviously the voters did overwhelmingly name Price as the league’s MVP (and so did the players). But Greenberg was not so much predicting the result as making a claim from historical evidence, which means that it is not the presence of hindsight that allows me to challenge his assertion. I’m not interested in criticizing anybody because their guy didn’t win, but I am quite interested in what history says about the relative comparison of forwards vs. goalies, since that is an interesting problem of player valuation. My contention is that history actually shows that the voters were completely consistent in backing Price, and would in fact have been just as likely in years past to choose a goalie season equivalent to Price’s over a scoring season like Ovechkin’s.

Continue reading “Why History Suggests Carey Price Deserved the Hart Trophy”

Are Swedish Goalies Overvalued?

In doing the research for my post on Jacob Markstrom, one of the things I did was run the numbers for all Swedish goalies who have played in the NHL over the past 25 years. That chart didn’t end up making the final cut, but it was interesting enough on its own that I want to post it in here in the context of a discussion on the recent performance of Swedish goalies in the NHL and what that might be able to tell us about the effectiveness of that country’s goalie development model.

Here is the complete NHL performance of every goalie from Sweden since 1990, with league-average adjusted save percentages normalized to .914:

Two things stand out from that chart:

1. Sweden has really blossomed as a goalie producing country over the last decade (15 of the 23 Swedish goalies to ever play in the league have made their debut since the 2005 lockout).

2. The save percentage numbers are quite mediocre for the group as a whole, with the exception of the outstanding Henrik Lundqvist.

Continue reading “Are Swedish Goalies Overvalued?”

Predicting Playoff Success

From Alan Ryder’s Ten Laws of Hockey Analytics:

One important warning – do not confuse correlation with causation. The former is easy to prove, the latter is quite challenging. For example, carry-in zone entries yield more scoring chances than do dump-in zone entries. But this could mean that a carry-in is evidence of better neutral zone puck control rather than a cause of better offensive zone puck control.

Which of these variables do you think is the best predictor of playoff series winners in the NHL between 1984 and 1990? In other words, if you were betting on matchups back then and could only look up one stat for each team to influence your decision, which is the one that would most frequently point to the eventual victor?

Goals For
Goals Against
Shot Differential
Team Shooting Percentage
Ratio of Shorthanded Goals For vs. Against

It’s gotta be #3, right, based on what we know about the importance of possession? Or maybe #1 or #4, since offence had to be important in a league that was wide open and high-scoring? Or perhaps that old saw about defence winning championships held true, and it was really #2? The one that seems most out of place is #5, a variable measuring rare events that doesn’t take into account anything that happens during the game’s most frequent and important game situation (even strength).

But if we look at the numbers after the jump, we get some surprising results:

Continue reading “Predicting Playoff Success”

Arbitrary Endpoints, Career Numbers, and the Future of Jacob Markstrom

One of the things I have been thinking about lately, and something I wanted to bring up in my first post back, is the issue of career stats and arbitrary endpoints, to borrow a term used by ESPN sabermetrician Keith Law. Here’s the description from Law’s glossary:

#arbitraryendpoints: Also known as cherry-picking, this means choosing one or both endpoints on a series of games to try to analyze a player. I’ve argued that it’s not arbitrary if the endpoint is tied to something specific, like a change in mechanics, an injury, or a recall from the minors, but even so, it’s always dangerous to throw out any data when you want to draw a conclusion.

I definitely agree that it is dangerous to throw out data and that it should never be done for the purposes of supporting an already-reached conclusion. However, I also agree that it is not always arbitrary to look at splits and segments of data rather than relying on the complete sample if there is good reason to expect that some of the data is not representative of an athlete’s true talent level.

There seems to be an increasing trend on Hockey Twitter for people to simply pull up a goalie’s career save percentage or career EV SV% and use that as the final verdict on their talent level. This can certainly be appropriate some of the time, perhaps even most of the time. I still think that goaltending is above all else a results business, and that statistical measurements remain very powerful methods of evaluating performance. That’s why save percentage over a large sample size is usually a good proxy for a goalie’s talent level. However it is still only a proxy, and the three points mentioned by Law do also apply to goaltenders. In the same way that Law might discount a pitcher’s performance in his first year back from an arm injury, we might have reason to believe that a goalie could be deviating from his historical average because he is not yet at 100% health after coming back from some time off or has made some changes in his game after working with a new goalie coach.

On top of those factors there are others more specific to hockey goalies, such as team effects/shot quality, situational performance (e.g. EV vs. PK), home scorer bias/road performance, usage, etc. These factors generally do not have a major impact on stats, but margins are so slim in goaltending that even a slight advantage or disadvantage can have an effect on the rankings. Overall, I think sometimes insight can be missed by looking only at the big picture, and in those cases it is appropriate to take a deeper look. And I’ll start doing that by focusing a magnifying glass on the short but interesting pro career of Jacob Markstrom.

Continue reading “Arbitrary Endpoints, Career Numbers, and the Future of Jacob Markstrom”