Related to the question of whether or not it's become easier to have an above-average game in the recent era (where league average save percentages are higher)...
My theory would have been the opposite of the claim above, based on the data shown here:
http://hfboards.mandatory.com/showthread.php?t=1830333
(Short version: when the league average save percentage is lower, there's more room to exceed it).
To test my theory, I pulled NHL seasons at five-year intervals (2013-14, back to the earliest season where I'd done the game logs), and looked at league totals for BAV (below -0.5 SD), AVG, and AAV (above +0.5 SD) games. The totals by year surprised me:
SEASON|BAV|AVG|AAV
1983-84|28%|35%|37%
1988-89|28%|34%|37%
1993-94|26%|38%|36%
1998-99|27%|34%|38%
2003-04|27%|37%|36%
2008-09|28%|36%|36%
2013-14|26%|37%|37%
So...it hasn't really gotten easier to have a high save percentage game (relative to the league), nor has it gotten easier to have a stinker (relative to the league).
As for why the proportion of below-average games is not the same as the proportion of above-average games, I would attribute this to two things (in descending order of importance).
- When a goaltender is having a stinker, he's more likely to be pulled early. Since my totals are shots-weighted, this lessens the impact of stinkers on the result.
- A (very small) positive correlation between shots faced and save percentages - goalies facing more shots have slightly higher save percentages. Since my totals are shots-weighted, you would expect to see slightly more above average games.
I welcome other theories, of course.
This is interesting, thanks for posting. I would have assumed that below average games would have shrunk more due to the proliferation of the butterfly and the cookie cutter goalies...not exactly the case though.
My issue is more complicated. You can slice up save pct. any way you want, and God knows you and others have done some very creative and interesting things regarding it...but I just don't take all those numbers at face value. You can coach Corsi, you can coach save pct.
Doc, I think you live out that way, Semyon Varlamov doesn't face the same type of workload that Brian Elliott does...Kari Lehtonen doesn't face the same type of shots that 2011 Tim Thomas did or 2012 Tuukka Rask or whatever...
And I know that some of the stats guys don't believe in shot quality and that it all evens out...that's fine if that's you see it, but that's the line in the sand for me...there's just no way that's true for me...zero percent chance to put it numerically. I'm not saying every save Jaro Halak has to make is a ten-bell job or that poor Jonathan Bernier has to go to the ER after every game at the ACC...but on the whole, these guys play on highly unattentive teams...
The Penguins are what I know best, I saw every single game of the Dan Bylsma era in Pittsburgh. The Penguins had the puck a lot, so they didn't give up a ton of shots. So, not giving up a ton of shots is deemed - still - as being a good defensive team. But the Penguins were not good defensively. Not in the neutral zone, definitely not in their own zone, they weren't tough near the crease, their retrieval/breakout system was based on high risk timing and touch passes deep in their own zone and in front of their own net. It was juggling faberge eggs most of the time...
Even players that left, particularly defensemen, remarked how difficult it was to pick up and execute...if it worked it was awesome, if it didn't, it was a total disaster with little chance of recovery.
These things just aren't taken into account numerically, and frankly, they really can't be...or it would be very difficult to. It's not just shot distance, quantity, or the player that's shooting or who is on the ice against it...there's just more to it than that...painting things with the broad save pct. brush just doesn't do it for me. But then again, most statistics do not. So I'm not the best person to ask (who asked me anyhow...) but if a player under-performs or out-performs his technical abilities, something caused it. Especially to the extent that we're talking about. A player who was not good enough for the NHL, came into the NHL and was not good, then popped off two non-consecutive Godly seasons, then left that perch and became barely good enough for the NHL shortly thereafter should raise such a huge amount of questions to a voter, an on-looker, a random pedestrian that it's hard to believe it's just accepted based on a save pct. number that has been ballooned for nearly every goalie in not only Claude Julien's Boston tenure, but Claude Julien's coaching career...
I mean, Boston is playing like crap this year...and Rask is still probably looking at another top-10 save pct. finish. Which is poor form, as he's normally top-3 I would think...
Say what you will about Thomas, call him a Mahogany God for all I care, it goes well beyond that rotund rubber regurgitator...we just need to be much more careful today with the advancement of coaching tactics, particularly defensive ones, and their influence on goalies and their averaging statistics.
We don't have video of Alec Connell (the all-time GAA leader), so we have to go by what we have. But when we have the ability to merge video with our paper products here, it's important to take advantage of that. Merge the actual game with the output that is produced from it, that's when we'll really be cooking with gas...the numbers are a product of the game, not the other way around. Durnan, Hainsworth, Connell, even Dryden...they got a little bit of that "yeah, but..." tag on them...and that's with multiple concentrated years of success (influenced by outside factors in some cases, of course), we have to make sure we're picking these out when we're in the moment as well...though tougher, it's just as important if we're going to create lists like this and have discussions like this...