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Everything you need to know to learn about hockey analytics

A rant about stats arguments, and links to more primers than stats beginners could possibly need.

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Geoff Burke-USA TODAY Sports

By far one of the most frustrating things about being a hockey fan these days is the endless debate about so-called advanced stats and how much value they add. More often than not, people are just doing it to stir things up, whether it's because they're bored, or they want attention, or would like some clicks and are being lazy about it, or whatever. Still, there are some arguments that happen in earnest, and unfortunately they descend into pile-ons and name-calling and smug superiority and some serious hockey buzz-killing.

I have some very strong feelings about this. Strong, angry, I-have-lost-my-patience feelings about this. Please allow me to share them.

  • What is all this stuff for, anyway? In simplest terms, it captures some things that wins and losses don't. Advanced stats may not tell you who will win a game, but over time, they can give you a more accurate picture of the way a team is playing (the 'process' you so often hear about), and what teams are likely to keep winning. A win streak can mask certain problems that can be seen by delving a little deeper.

  • There is literally nobody who believes in advanced-stats analysis to the exclusion of all else, so please stop accusing people of this, unless you have specific examples of this happening. Everyone watches the games, everyone likes that perfect defensive play that doesn't get recorded on a stats sheet, and everyone actually enjoys sports for sports' sake. Some just enjoy seeing the game at all levels.

  • If you don't believe in advanced stats, or think they have no value, feel free to express that, but please do it knowing that this normally results in people trying to show you the error of your ways, calling you a dinosaur, or piling on. If your job involves covering hockey for a defined audience, and that defined audience is beginning to wise up to stats and their value, you might wanna look into learning about them (or just not saying anything) instead of denying their worth, because loudly denying their worth is not going to mean your audience will blindly listen to you and change their minds. They will instead go look for hockey coverage (stats-based or otherwise) from people who don't think they're idiots. This is the internet. We all have lots of options.

  • If you're a stats person, please stop freaking out every time someone denies the value of stats. Please just ignore these people. If you stop paying attention to them, they will eventually just go away. If you argue with them, you are dignifying all the baiting they do with your response.

    Nobody is telling you or anyone else how to watch hockey. But you can expand the way you analyze hockey if you want.
  • If you're a fan, nobody is telling you or anyone else how to watch hockey, or how to enjoy hockey. But you can expand the way you analyze hockey if you want. If you want to watch hockey without the stats, that's fine, and no one is saying you absolutely have to. This is a misconception about the advanced stats crowd. We're just saying there's added value in it. Just because we think teams should be looking at these stats, doesn't mean we think you should know them before you can enjoy that goal or save or pass or whatever.

  • However, if you decide you want to argue with stats people (and especially if you want to tell them they're wrong) you kind of have no choice but to learn about stats. Think of it in terms of two different languages. If you want to tell someone who uses (and is well versed in) advanced stats that you disagree with them about something, but you can't explain why in terms of stats, it would be like having an argument in English about French when you don`t speak French and they do. In much the same way, if someone is trying to disagree with you using only stats, and you don't understand any of them, they're basically just telling you you're wrong and not why. It's frustrating for both sides, and it's one of the reasons these discussions don't get anywhere. The good news is that this stuff isn't that hard to learn.

  • Nobody is telling you that you can't enjoy a win. You can know your team is playing a god-awful puck possession game but still enjoy it if they overcome that and win the game. Especially if they beat the Boston Bruins. This was what being a Habs fan was like for much of the last season.

  • With a few notable exceptions, people who argue with you using stats are not trying to make you feel stupid - they're trying to explain why they disagree with you. Sometimes that explanation can come across as as mean or obnoxious when that is likely not the intention, and the internet does not always allow for tone. Nice stats people exist. I promise.

  • If you ask someone a question and they respond with a link to an explanation, they are not trying to dismiss you just to be a jerk. They are providing you with an explanation. Not because they are being lazy, but because a paragraph or visuals explain a concept better than a tweet ever could. Someone did a lot of work to explain something, so it's going to take a little work to understand that thing. Click, read, ask follow-up questions. We are all here to help, but it's a two-way street. I promise you, we don't think you're stupid ... unless you're yelling at us about "heart" and "wins" and "good in the room" twenty times on Twitter without listening to our responses.

  • "Yeah, but what is his CORSI?" is not funny, it's not original, and nobody thinks you are smart if you keep replying to stats people that way on Twitter.

Okay, so now that that's out of the way and I feel so much better (thanks for listening), let's get to work.

If you believe that luck plays a part in hockey (or sports, or life, or anything) outcomes and that the team that maintains puck possession for longer is playing better than its opponent... then I hate to break it to you, but you are a proponent of "advanced stats." You nerd. We are all into fancy stats. I'm sorry you had to find out this way.

It's really that simple. I'm convinced the terrible names for most of these stats make up 90 per cent of the reason people think stats are invented and also advanced. If we called ‘Corsi' ‘shot-attempt differential' and ‘advanced stats' ‘common sense metrics' then there wouldn't be such a huge debate about it, and it wouldn't seem so difficult.

If you're a beginner who has no idea where to start, you're in luck. We've put together a collection of links that will help you learn everything you need to know, especially if you have absolutely no idea what in Koivu's name a "Fenwick" is even though you keep hearing about it.

After what happened to the Toronto Maple Leafs, as well as the ultimate result in the Stanley Cup playoffs, you can bet that a whole lot more people are going to be using advanced analytics in their hockey coverage next season. In fact, even throughout this past hockey season, you'll likely have noticed that the number of people expressing curiosity about so-called "advanced stats" is steadily increasing. People are starting to warm to the idea of incorporating these stats into their discussion of hockey, but often don't know where to start or how to go from the basics into what seems like the more complicated stuff.

Now that the playoffs are officially over, there's plenty of time to learn about or brush up on this stuff, and the dearth of hockey news is going to mean people will have more time to help you. So there's no time like the present to start.

When I first started learning about this stuff, there weren't really very many accessible guides or primers out there. I would ask a lot of questions of people and have them explain everything to me, sometimes multiple times. Nobody told me to go away or told me I was an idiot for asking. Over the last couple of years, though, some awesome stuff has made its way onto the interwebs, which makes it really simple to learn about advanced stats.

What to read: your fancy stats library.

To start, you're going to need a primer that explains the basic concepts. Luckily, there are about a million out there. The links below are pretty different from each other, but they're all about the same things. Some are simpler than others, and some come off as a bit pedantic, but I've included them because some people are into that. It's up to you to find the one that works for you and give it some time and a chance. It's not hard, but it does demand your attention. Happy reading!

EOTP fancy stats summer school: Last year, EOTP ran a series called fancy stats summer school right here, devoting a post to simplifying each concept (in English and French). You will find all of the posts here.

Down Goes Brown's Primer: when I crowdsourced Twitter to find out which guide people found useful, this one was the most popular response. Everything you can do, DGB can do better, only he's really nice about it so you can't even get mad. He's done a few other pieces since, and you can start here if you're interested in more.

Friend of EOTP Jen LC did a primer (Part 1 and Part 2) over at Second City Hockey. Jen writes some very accessible stats-based posts in general, so she's a great follow on Twitter as well.

Eric T is my favourite analytics-based hockey writer. Here is a Twitter Q and A he did, and here is a quick guide he did at the beginning of the last season. Literally everything he writes is enlightening. Everything. Without exception. You can also check out Outnumbered, where Eric posts regularly about interesting things.

Would you like a wealth of knowledge on advanced stats? The people at Arctic Ice Hockey have a zillion articles. If you want to know why a metric is important, go there, there's probably an article explaining it.

In that same vein, here is a post about what we get from advanced stats from the aptly-named Death By Leafs.

This isn't a primer, but quick and worth a read. The Leafs Nation ran an article making an advanced stats argument in shinny hockey terms. It was fantastic.

NHLNumbers is another place to find regular pieces on all number of stats-related analysis, including a crash course on possession.

mc79hockey regularly posts stats- and research-based articles about all number of hockey topics. They're well-explained and easy to understand.

Finally, Behind the Net: this is where it all started, and it's basically the definitive resource. There is a guide to using the site on the front page. I listed it last because it's the most intense of the lot.

Where to go: some sites that measure everything you could possibly need.

Alright, so now you know what all these numbers are, but trying to calculate any of them every time you watch a game would seriously bum you out. Thank Saku for nerds on the internet.

Enter Extra Skater, the site that I wish were a human so I could marry it. It has data on every team, every player, and every game (playoffs), dating back to the 2011-2012 season, and not just in the NHL. They even recently added CHL stats! If you click on it and get overwhelmed because it's basically a bunch of acronyms and numbers, don't worry. It gave me headaches at first, too. Here's a glossary. Also you can ask anyone who uses the site regularly how they use it to help you figure it out. Once you start using it, you won't be able to stop.

Super shot search is a site you can use to search for shot location by players, against goalies, and by or against a team. You can also see team/player scoring chances for or against, shooting percentage, save percentage and a whole load of player usage charts. It's really cool.

Shift Chart is a chaotic, scary-looking tool that is really as simple as its name. You can use it to visualise players' shifts on the ice. I love it.

Follow Corey Sznajder on Twitter (@shutdownline) for all kinds of stats info; he's working on a project to compile zone entries for all 30 teams over an entire season and always has good information to share.

Nice Time On Ice is kind of like a one-stop shop that links to almost any information you could need from any game you want to look up dating back to 2007-2008.

If you're on Twitter, I made a list of people who regularly talk or write about stats. You can find it here. I update it regularly, so if you see anyone I've missed, please hit me up on Twitter with their handle.