Aavco Cup
"I can make you cry in this room"
- Sep 5, 2013
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I think it ignores a goalie's rebound control. (and I asked the author that question, I'm interested in his response). It looks like delta is assuming that goalie positioning, rebound control, and puck handling is all the same from goalie to goalie (at least from his description). I mean, I watched Pavelec for years... Helle makes it way easier on his D.Hopefully this isn't too off-topic, but I don't know where else it belongs.
In reading up on the Vezina finalists, I noticed a definite shift in the fancy stats analysis of goaltenders. A few years ago, I got in many arguments that raw sv% was an unfair measure of a goalie's performance, since it didn't account for the team's defensive play. At the time, fancy stats guys "in the know" discredited the effect the team in front of a goaltender had on the number of saves. Basically stating that "it all evened out". And that sv% was a pure indicator of a goaltender's ability.
Here's an article discussing the fancy stats behind the Vezina finalists.
Earning the Vezina 2018, Part 2: Advanced stats and the rightful winner - InGoal Magazine
It says that, while Hellebuyck has been great, there are other goaltenders with lower sv% that have been even better. It factors in the kinds of shots the goalie faces.
This article states what many of us "eye test" folks argued all along, quote:
Raw save percentage treats every shot as though it were equally difficult to stop. Saving a muffin from the red line or a perfectly-executed 2-on-0 are worth exactly the same amount. This would be fine if the total difficulty of shots faced averaged out for all goalies over the course of a season, but this doesn’t happen: goalies who play on worse defensive teams face more difficult shots overall. This means that even if two goalies sport an identical league-average 91.2 save percentage, one might have significantly outplayed the other in order to earn it.
There now appears to be a term for this team-dependent goalie measure, called delta save percentage.
I'm a firm believer in fancy stats. But I also consider it a young art, and I think this is a case where the fancy stats have finally caught up with what eye-test folks saw all along.
Thoughts?
Hopefully this isn't too off-topic, but I don't know where else it belongs.
In reading up on the Vezina finalists, I noticed a definite shift in the fancy stats analysis of goaltenders. A few years ago, I got in many arguments that raw sv% was an unfair measure of a goalie's performance, since it didn't account for the team's defensive play. At the time, fancy stats guys "in the know" discredited the effect the team in front of a goaltender had on the number of saves. Basically stating that "it all evened out". And that sv% was a pure indicator of a goaltender's ability.
Here's an article discussing the fancy stats behind the Vezina finalists.
Earning the Vezina 2018, Part 2: Advanced stats and the rightful winner - InGoal Magazine
It says that, while Hellebuyck has been great, there are other goaltenders with lower sv% that have been even better. It factors in the kinds of shots the goalie faces.
This article states what many of us "eye test" folks argued all along, quote:
Raw save percentage treats every shot as though it were equally difficult to stop. Saving a muffin from the red line or a perfectly-executed 2-on-0 are worth exactly the same amount. This would be fine if the total difficulty of shots faced averaged out for all goalies over the course of a season, but this doesn’t happen: goalies who play on worse defensive teams face more difficult shots overall. This means that even if two goalies sport an identical league-average 91.2 save percentage, one might have significantly outplayed the other in order to earn it.
There now appears to be a term for this team-dependent goalie measure, called delta save percentage.
I'm a firm believer in fancy stats. But I also consider it a young art, and I think this is a case where the fancy stats have finally caught up with what eye-test folks saw all along.
Thoughts?
I think it ignores a goalie's rebound control. (and I asked the author that question, I'm interested in his response). It looks like delta is assuming that goalie positioning, rebound control, and puck handling is all the same from goalie to goalie (at least from his description). I mean, I watched Pavelec for years... Helle makes it way easier on his D.
Thing is, "eye test folks" don't all agree. So while there may have been some that saw it all along, most did not. So including even the rudimentary stats when formulating your opinion will usually improve it.
Apparently the author can't handle questions. I didn't criticize, just asked how rebound control played into his article, but the comment didn't make it past moderation. Weird. Other analytical websites don't mind discussion.That's a great point. Poor rebound control would increase the high-danger chances, at no fault of the team in front of the goalie. Maybe the model will evolve to track and measure rebounds as well. But I agree that, until it does, it's a short-coming of the current methodology.