A Primer for Advanced Stats - need your input
Even my friends and family have been telling that the documentation on behindthenet.ca sucks. Guilty as charged - a lot of what I've posted there is stuff for personal use that basically all of seven people in the world can figure out and make use of. So I wrote a short primer with links to some salient points that appears below...Let me know if you have any comments or suggestions or if there are any major items you think I missed.
About Advanced Statistics: The Basis for this Site
A Guided Tour through Advanced Statistics on Behindthenet.ca
Let's start with team statistics. First, Goal and Shot Rates at 5-on-5 - you can find data for all other strengths on the same page, but we focus on 5-on-5 because roughly 3/4 of NHL games are played at 5-on-5. A team that dominates shot differential at 5-on-5 tends to have very good playoff outcomes, for example, Detroit in 2007-08 or 2008-09, Chicago in 2009-10 and Vancouver in 2010-11. Shot differential is obviously not the be-all and end-all of team performance; we'll get back to that later. It's also important to keep in mind that shot differential exhibits a lot of what are known as score effects: the later we get into a game, the more shots the trailing team takes and the fewer the leading team takes as it protects its lead. To account for that, we also track Fenwick (Corsi excluding blocked shots) by game score, and in what's known as "close situations" - tie games and in the first and second periods of games within two goals. The best "Fenwick Close" score that any team has achieved in the last five seasons is Detroit's 59.4% in 2007-08.
Equally important is the concept of PDO, which is simply the sum of save percentage and shooting percentage. In the long-run, PDO regresses very heavily to 1000; rare is the team that is able to stay consistently above this level, though every year, people claim that some team can out-finish their opponents while failing to out-shoot them. Examples include Colorado in 2009-10, Dallas in 2010-11 and Minnesota in 2011-12 - all three teams came crashing down to earth way before the season ended. When you want to know how a team is going to do going forward, out-shooting is way more important than out-finishing.
Individual Player Statistics
Unlike team-level stats, individual stats are also driven by how a coach chooses to use a player. Here, the two most-important metrics are Offensive Zone Starts and Quality of Competition. It should be obvious that players who get sent out for a lot of offensive zone faceoffs are more likely to direct a shot on goal than surrender one, and Offensive Zone Start percentage captures this. The Vancouver Canucks have taken zone starts to an extreme during the 2011-12 season, with the Sedins and Alex Burrows starting in the offensive end more than 75% of the time, while the Malhotra-Wiese-Lapierre line starts in the defensive zone more than 80% of the time.
Measuring Quality of Competition is less straight-forward: we take the ice time-weighted average of a player's opponents' Corsi number relative to his teammates. The leaders over the last four seasons are a who's who of top defensive players: Nicklas Lidstrom, Willie Mitchell, Dave Bolland, Sammy Pahlsson, Rob Niedermayer, Brent Seabrook, Joel Ward, Jay Bouwmeester, Chris Phillips and Jan Hejda. A primer on the impact of Quality of Competition and Offensive Zone Starts can be found here.
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Hockey is just screaming for a good & valid stat regimine
good luck!
Fighting stupidity since 1958 (its a much bigger project than originally envisioned).
Confusion will be my epitaph.
It needs more cowbell.
Since I've got you on the phone (so to speak)
I am very new to the whole stats thing, and I am NOT mathematically-inclined or all that computer-savvy. Somehow it has fallen to me to cover the Lightning’s statistical analysis over at the Raw Charge blog, and while understanding the stats is a challenge, getting to them is worse.
Just off the top of my head, I need data broken down by date. For instance, I was trying to figure out what changed when Eric Brewer joined the Lightning in Feb of 2011 and I could not find Corsi or shot data broken down by game to be able to make that before and after comparison. The new Fenwick charts are wonders in this regard but don’t help me with power play data. Is this sort of thing available anywhere? I’ve been pulling it from multiple sources and compiling it, but that’s quite a bit of work and there are projects I’ve just dropped because of it.
And may I also ask for a tutorial/primer in how to actually get to the stats on your site. Using that 1+2+3+4 thing makes my ears bleed. No offense; I’m just sometimes unable to get it to actually include the data that I need and not the data that I don’t. Is there a way to explain that to dummies like me?
R.I.P. Belak, Rypien, Boogaard, Lokomotiv.
"You don’t motivate people; you activate something in them that already exists." -Guy Boucher
" I saw it, I called it, I still don't believe it!"--Pete Weber

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