Questions for Quinn: Diving into analytics… HELP ME!

Oh boy, here we go on something that, if I’m being honest, is not something that I took a lot of interest in. But this was a good way for me to dive head first in to it and have a little fun with…ANALYTICS.

I got the question: How did we go from +/- is a junk stat, to again using it, but only if it’s called goal differential at 5v5?

What’s funny is that I loved a +/- stat; I used it a lot in stories when I worked in mainstream media… clearly, I’m just simple minded because it makes sense to me.

But doing some research on this question, I’ve very much turned a corner and feel a little foolish. I have some friends deep in the trenches of analytics for different hockey teams, so I turned to my pal for some guidance on this issue. (Honestly, I’m calling it an issue because it’s something that’s hard for me, I’ll be the first to admit it.)

To make a long story short, like many old things, +/- was there was at the time. But it has since been shown to be unreliable because it relies on goals, which are very rare in comparison to shot-based metrics. Measuring goals makes it more random and less reliable. Then when you add in the nuances of special teams (you don’t get a plus for a PPG, but you get a dash for a SHGA) and empty net goals, it further skews the information that doesn’t reflect 5v5.

ARE YOU STILL WITH ME? AM I STILL WITH ME?

So, to give you some examples, let’s say a player is on a team with a really great power play for one season that has a very high power play goal/short handed goal differential, but gives up a lot of short handed goals against, the player would get minuses for all those but it doesn’t mean he’s a bad defensive player at even strength. The same goes for a good player on a bad team (we’ve seen a few of those in our time here); let’s say his team spends a lot of time with its goalie pulled, they’d get scored on a lot at five-versus-6 and that’s not the same game state five-on-five, so (obviously) quite an unfair stat in that respect.

When I asked him about what teams were looking at aside from +/- he said it is all very high level, looking at shot rates with some measurement of shot quality. He said the video recognition software is taking things a lot further as each game can generate a lot of data that us everyday fans wouldn’t even think of.

I really hoped that helped a bit. Basically, it just wasn’t fair to players to measure +/- because of the variances in game situations, so we have to measure only 5v5. Reading other articles online I’m feeling a little intimidated and embarrassed about all this, but this felt more simple for me than many of them.

And hey, this analytics thing could be something I dive deep into. I must thank him as I basically used verbatim what he told me in a lot of this article; he’s so in tune and was able to make it fairly simple.

Keep the questions coming, folks! Remember you can leave a comment or catch me on Twitter: @QJPhillips.