Originally Posted by CorsiHockeyLeague
Again, you have demonstrated that you don't know what you're talking about.
League-wide, it does, by necessity. As I said, it's just a shorthand. If you see a team at the top of the standings you weren't expecting, you look at the league PDO table, and if their PDO is high, then you can say, okay, well, their shooting percentage or save percentage (or both) is probably driving that. Then you'd have to do a lot more looking to figure out what's really going on. It's just an off-the-cuff indicator about how a team is winning (or not).
And this is garbage. What is it telling me that SV% and SH% isn't telling me already? Gee golly, I need someone to tell me how these add up... and why in the holy hell SHOULD it add up to 100? Do you expect a good team to just be 100? And a bad team to be 100? And that any deviation of 100 is either based on good luck and bad luck, and that they will return to 0 because, well, they just absolutely should add up to 100? See the point I am making. It is a garbage stat. SH% is useful. SV% is useful. PDO is garbage. At least qualifying it by saying it is either lucky or unlucky is garbage. So yes, it is a garbage stat.
Totally, but then you have to effectively discard stats as a useful tool to tell you anything about how a team is doing and just go with "we won / lost the game, that's all that matters". All these things are useful for is to give you more information about what trends are going on throughout the season, which hopefully will indicate - better than the win / loss record - what's likely to happen if X or Y tweak was made. No one is suggesting that Fenwick or XGF or RelTM can reliably predict the future; otherwise everyone would make a killing betting on hockey.
But that isn't the argument that I am making here, so don't twist this into that. Re-read what you just replied to - I AGREE with the analytics that are out there (well, most of it), but it isn't ACCURATE or COMPLETE enough. That's it. That's all that I am saying. Though you can see trends - and that is always welcome, there are simply too many outliers given what you are referencing to draw conclusions 100% off of. I wish I remembered - ok, I wish I felt inclined enough to search for it online and post it here - but an actual actuary took at look at CORSI and laughed at it saying he would be fired for providing guidance on anything with this low of confidence intervals. CORSI is useful, it is interesting, and it can help in digesting the guts of the game, but it is hardly the conclusive statistical model that is irrefutable - it certainly isn't what you claim it to be.
I have neither passionately defended them, nor have I suggested they're "infallible". I suspect your very long post would be shortened somewhat if it just responded to what I said, instead of creating straw men.
Pot meet kettle.
No - hilariously wrong, considering this is a basic stat that has been publicly tracked and available for well over a decade now. Corsi is shot attempts including blocked shots; you don't deduct anything. What you've described is Corsi +/-, which I don't know of anyone referencing when Corsi% is available.
It's also not exactly possession - it's offensive zone possession. Or rather, a proxy for offensive zone possession. So are shots on goal, and goals, by the way. Shot attempts just create more data points. It's just more information... You can use it to support well-reasoned conclusions or poorly reasoned ones. There's nothing inherently good or bad about data.
There isn't anything inherently good or bad, but the way in which they are used and the conclusions that can be drawn can be good or bad. That's the point I am making. Agree or disagree?
You seem to have strong opinions on these stats but can't actually describe them at even a basic level. I'd hate to see the gears turning as you attempt to figure out RelTM.
Thanks. Get bent.
This is really obvious, which is why you just have to take a look at the home / road splits to determine if anything particularly funny is going on, which it typically isn't.
Except, first, that's not the case, based on the limited numbers of times that various people ten plus years ago just used a stopwatch to calculate offensive possession and then compared it to the corsi numbers and determined that they're basically the same. But whatever, if you want to just dream up hypothetical teams that cycle the puck around and don't try to shoot it, go ahead. The reality is that those teams tend to a) actually take more shots, and b) spend less time in their own end because they spend it in the other team's, so it winds up being a wash. But you dream up whatever scenarios you like, if that's what makes you happy.
"They're basically the same" is not THE SAME. Sorry, but inferencing possession by how many shots are taken is not the same thing as actual possession. Numbers get skewed. How much does it get skewed? I don't know. I anticipate that systems, how teams are built, how talented teams are, etc., can skew results for an entire season or more. Like I said, CORSI isn't garbage, but people like to take this too far. Heck, just look at Edmonton and how Eakins tried to 'play for CORSI' - Eberle and a couple of other players said as much. You really don't believe that there COULD be discrepancies between CORSI and actual possession? It is still an indirect measurement, and it is also measuring shot attempts - you sure that was a shot not a pass or slap-pass? Are they being judged completely the same from building to building? Etc. There is still a lot of 'noise' in CORSI. But I guess the gears in my head must be getting rusted and need a bit of oil or something, so I must defer to the great CORSIHOCKEYLEAGUE to provide me with all the answers so that I don't have to think for myself.
Typically, yes. You can get by with your goalie bailing you out and having 12% of your shots go in for a month, and for about one team every year, longer. Long enough to make the playoffs, even. Hockey's a chaotic, frantic game with lots of variables and bounces.
Definitely agreed.
How do those teams do in the post-season compared to those that play hockey the "right way" from a possession standpoint? How do they do the following year? Like I said above, are we really doing this again? If you still think there's no correlation between being a good possession team and long-term success I just cannot help you.
FFS, stop extrapolating it into me saying it is the preferred way. My damn argument is that a team like Calgary's at the time - poorly constructed - who have no hope of winning the 'possession game', can figure out a way to still win. Is it optimal? Never said that. Can it be sustained - yes, through sheer hard-work, I believe it can be sustained. But hockey is also not static. Teams will try and figure out how they can put a stop to it. In the end, talent SHOULD win, as long as that talent is working cohesively. Does possession-type hockey result in more wins? Of COURSE IT DOES. It is like you aren't reading what I am saying. What I am saying is that CORSI has a correlation - the correlation is there for anyone to see - but there are simply too many outliers. Whether it is from a goalie playing lights-out for a long period (is it really the goalie, or the team helping the goalie out a lot?), to a team just struggling with confidence and not finishing (slumping), to a team with poor fitness (late night video games, bad team culture that likes to party too much, etc., etc., etc.).
Yeah, I'm not bothering with the rest of it. It's just a bunch of motivated reasoning and ex post facto justification of results that didn't hold up over time, just as anyone with a brain in their head could have predicted. You don't need to read the shot attempt differentials to figure out that having the puck more than the other guys is a good way to win.
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