Bayesian Analysis, Preseason, and Ryan Strome and Anders Lee.

Jonathan Willis wrote a post for Oilers Nation about how we should use Bayesian Analysis when it comes to preseason and training camp.  It’s a great post and I recommend you read it, but I want to expound upon it here quickly as it comes to the Isles.

“Bayesian Analysis” is a fancy name for a pretty simple and common sense concept.  If we know something about a player, a team, or anything really and then we acquire new knowledge about the player/team/thing, we shouldn’t just throw out our prior knowledge – even if the new knowledge contradicts our old understanding.  Instead we should evaluate how strong our prior understanding (our “prior”) was and how strong the new evidence is and combine the two to try and get a more complete picture.  If our prior is very strong, it should take very strong new evidence to change our mind to make us believe that our prior was wrong.  If our prior is weak, of course, it takes less strong evidence to change our minds.   You can do this with math (Willis demonstrates it in the post above), but it’s a really basic concept.

This is a pretty important thing to remember for preseason.  NHL Preseasons are VERY short.  We have only 7 games (two of which are split squad, so players can at most play in 6 of them) – of which players won’t play in every one of them.  We have a month of camp – which is not the same as game time obviously – for teams to look at players.  This is a very short time to evaluate over 40 players, 25-30 of which have a shot at making the roster.

In other words, the new information a team can obtain through preseason is never going to be very strong.  Even the best possible camp a player can have shouldn’t be considered that strong of evidence, as this is pretty much the definition of a “Small Sample Size.”  And so, if you have a strong prior at ALL about a player or group of players, training camp/preseason pretty much should NEVER change your mind.


Let’s look at two potential NHL forwards to see an example of what I mean.

Anders Lee:  Anders Lee is a guy who has never been a pretty highly rated prospect.  He was drafted late in a draft as an overager, wasnt even ranked top 100 CSS pre-draft, and some experts (Corey Pronman) didn’t even have him in the Isles top 5 prospects – hell Pronman didn’t even have him top 10.  So our prior going into last year was basically not to have high expectations.  Then he had a good AHL season and an incredibly good 22 NHL games – both in traditional and fancystats.

So going into camp, what’s our projection of Lee as an NHL player?  We should think he probably is ready to be one, and we should think there’s a chance, although not necessarily the highest chance, that he’s a top 6-er.  So our prior here, in an atmosphere where there are a ton of bodies competing for 12 jobs, isn’t super strong that he deserves one of them (especially given his waiver status).  So Training camp and preseason performance should influence us, and the team, a little bit.  It shouldn’t matter more than 22 NHL Games of course – seriously, think about that for a second – but it may influence us a little.

Ryan Strome:  By contrast, Strome has been the Isles top or one of their top 2 prospects since his draft day.  He was drafted 5th overall, and had strong juniors #s.  He debuted in the AHL last year and managed to LEAD THE LEAGUE in POINTS in mid-December, forcing a call up – all at age 20 (by contrast, Lee was 23).  Strome finished the AHL with 1.32 points per game in 37 games.  He then played 37 NHL games, managed 18 points despite frequently being with lousy linemates, and had good overall fancystats with a +3% relative corsi while not being sheltered.

So going into camp, what’s our projection of Strome as an NHL player?  Well we should be pretty damn sure he’s already capable of being one and we should be pretty damn convinced he’s a top 6-er.  He could have the absolute worst camp ever, absent injuries, and our opinion on Strome should still remain pretty much the same: He should make the team.  This doesn’t mean he should necessarily play Center over other guys, but there’s no chance you should be persuaded that he doesn’t deserve one of 8 wing spots over any of the other guys.  Our prior is that strong.


In short, everything we know about Ryan Strome, makes the idea that he has anything to prove in training camp absolutely absurd.  He’s got the pedigree, 37 amazing AHL games, and 37 strong NHL games behind him.  What exactly in 6 (less actually) preseason games and a month of camp should be able to change our minds about him?  How exactly can you believe, from anything in camp, that the team would be stronger for Strome off the team?

Only by forgetting what we know about Strome – about any players – prior to camp, can you make that argument.  And that’s obviously stupid (hey if Tavares had a bad camp, leave him off!).  Shouldn’t it be for the team as well?


3 thoughts on “Bayesian Analysis, Preseason, and Ryan Strome and Anders Lee.

  1. Lee was probably ignored by some because he was a 6th round pick the same year that some other guy was #1 overall. He was passed over because everyone assumed he would be a pro football QB, He has been a dominant player everywhere (USHL, college, AHL) he played before the NHL. Not his fault others weren’t paying attention.

    IMHO he’d be a perfect fit as top line LW. He could create space for JT and KO and is obviously quite able to score as well. That said, conacher acquitted himself well tonight. Lee and Strome are both capable of playing at the NHL level but that doesn’t mean they should be guaranteed roster spots.


    • Not going to argue lee’s pedigree for the umpteenth time but okay even if we believe that’s true that just gives us a stronger prior regarding him. As such we should care even less about training camp/preseason.

      The idea that strome isn’t guaranteed a roster spot is missing the point . What guarantees tavares a roster spot? It’s not preseason- it’s all he’s done beforehand. Same is true of strome already- he’s dominated the level below and played strongly at the nhl level, better than many of the guys who are seemingly ahead of him (you mentioned conacher, I did not). Preseason simply doesn’t give you enough information to change that.


  2. Enjoy the site, keep up the good work Garik.

    Disagree about Strome. Unlike Tavares, Ryan has not done nearly enough to earn an automatic spot on this team. I would argue that Bailey, who I wish was not on the Isles, has more substantial body if work and is more of an automatic.

    Strome should remain if he is good enough today to be on the top 6. If he isn’t, and he doesn’t look like it to me so far, he should got top line time in Bridgeport.

    Would easily start Conacher over Strome to start the season. For that matter, I’d take Lee over Strome as well.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s