Context is Important – But its just as Important not to OVEREMPHASIZE it.

One of the most frequent complaints “anti-analytics” people make about so-called advanced stats is that these stats fail to adjust for context – some players have harder minutes than others.  This complaint is of course bunk, and a complete straw man – analytics has come up with numerous methods on calculating how difficult a player’s minutes are: From measures of competition, to measures of teammates, to measures that contextualize where players start their shifts most often (zone starts) – we have multiple metrics to explain EACH of these things.  Sure you can use fancystats incorrectly and completely ignore context, but good analytics work doesn’t do that, and it’s pretty easy to see where someone is and isn’t attempting to take into account context.

That said, with the new season coming up, it’s important to remember not to go TOO FAR when doing this.  That is, context is important, but context doesn’t explain EVERYTHING.  And people often tend to forget this.

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The Process of Drafting Goalies: – A look at Isles’ goalie drafting since 2008

I wrote a piece on Hockey-Graphs this week about how we should and should not draft goalies in the NHL and whether things will change.  I wanted to apply this to the Islanders’ drafts from the Garth Snow era.  For those who are unfamiliar with how analytics treats goalie drafting, and I went over how we deal with goalies in general in my last livecast:

But in sum, there are a few points to remember about goalies:

1.  Goalies are HIGHLY variable over single seasons due to small sample sizes and the small differences between NHL goalies.  A goalie can be great one year and then be lousy the next year -> in fact when a goalie does have a great year, we do expect him to take a clear step back the next year due to regression.  With relatively few exceptions (Rask), you should never sign goalies to long term or expensive contracts, because the odds of failure are really high.
2.  Goalies peak REALLY early (age 24 or thereabouts) and then decline throughout the rest of their career.  This is on average, of course – some individual goalies may peak later and some will not suffer the effects of aging for a while longer than we’d expect, but for the most part, goalies decline every year and expecting a goalie over 24 to get better is making a sucker’s bet.

The above two points would seem to emphasize the importance of drafting goalie talent – after all, drafted players are the cheapest (not expensive) and will be on your team at the youngest age, near a goalie’s peak, so as to avoid the issues of goalie decline you get on the free agent market (most goalies don’t hit UFA till age 28 or even mid 30s).  But this brings us to point 3:

3.  Goalie prospects are far more variable than skater prospects and have a much higher rate of failure, due to the difficulty of scouting goalies and the extreme small sample size of pre-draft goalie prospects.  As such, you generally should NOT draft goalies early, and probably never draft a goalie before the third round.

So yeah, this doesn’t make it easy – to a large extent, you simply have to get LUCKY to draft a good goalie.  But it helps to have a good process, such that bad goalie drafting luck doesn’t result in you missing out on better skating prospects than you have to.  So let’s look at Isles drafted goalies under Garth Snow:

 
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