I am sure this post will rattle some feathers in the Hockey Analytics community but hey, it won’t be the first time I have accomplished that.
I have been looking through the list of potential free agents looking for players that are possibly under valued, possibly over valued, or otherwise interesting for one reason or another. There has been a fair bit of discussion around the three players that are the focus of this post. Justin Williams has been a favourite of the hockey analytics community posting outstanding Corsi numbers year after year. Alexander Semin, who was bought out by the Carolina Hurricanes is one of those guys that seems to be hated by coaches, scouts, general managers, and “traditional hockey people” but analytics people look at his numbers and, last season aside, they look outstanding. Matt Beleskey is an unrestricted free agent that hockey analytics people want to warn teams about because he is coming off a career year with 22 goals driven largely by a high, and unsustainable, shooting percentage. The hockey analytics community are predicting he will be one of those guys teams will over pay for and regret the decision a year from now. So, I figured it would be worth while taking a deep look at these players because from my observations the deeper you look the more interesting things become and the story potentially changes.
I am rushing a bit to put this post together so it may come across as just me throwing out some numbers and charts. I apologize for that but bear with me, there is an interesting story that will develop.
For this post all numbers will be 5v5close numbers to minimize the impact of score effects. I am also going to focus on my RelTM statistics which look at how each player influences his line mates. It is like a combined WOWY analysis where we can determine whether the players teammates perform better with him or apart from him.
Let’s look at the corsi statistics first starting with the offensive and defensive components and then corsi percentage.
Here higher is better as it means teammates have a higher CF60 with them than apart from them. The 3-year average is their CF60RelTM over the past 3 seasons. For the most part Williams is the best, Beleskey is the worst and Semin bounces around a bit.
Here lower is better as it indicates there are fewer shots against when players are playing with them than apart from them. Things looked a little differently this past season but prior to that Williams was always better than Beleskey and Semin bounced around a bit. This past season both Beleskey and Semin were better than Williams.
Higher is better on this chart. What we see is Beleskey is getting better, Williams is getting worse and Semin is relatively stagnant or maybe a slight drop off. Last season the three players were almost identical. One has to wonder if age effects are taking place here as Beleskey is 27 years old and has been entering his prime years and Williams is 33 years old and is starting to leave his prime years. Semin is 31 has been in his prime years and may just be starting his decline.
Corsi is a useful metric but I believe if you have multiple seasons worth of data you have to look at the goal data for trends as well because goals are what really matters. What is interesting is that with these three players it tells a somewhat different story.
Recall that for CF60 RelTM we saw Williams always better than Beleskey and Semin bouncing around a bit. Here we see Beleskey starting off below Semin and Williams but the past couple of seasons has surpasses both of them and has had the better GF60 RelTM. Once again Beleskey is improving, Williams and Semin have fallen off some.
Lower is better so this is pretty much a repeat of GF60 RelTM. Beleskey is improving and has easily had the better GA60 RelTM, particularly the past two seasons.
As one would expect, Beleskey clearly has the better CF% RelTM the past couple seasons. What is interesting is hockey analytics favourite Justin Williams has had a negative GF%RelTM in 3 of the past 4 seasons despite having a CF%RelTM well above 0 in each of the last four seasons. Beleskey has had four straight seasons with a GF%RelTM above zero.
To summarize the above charts, Justin Williams looks far better when looking at Corsi than when looking at goals while for Beleskey it is almost the opposite. Furthermore Williams seems to be starting to show his age and starting to decline while the younger Beleskey appears to still be improving. To explain the divergence between Corsi and goals data lets have a look at two more charts: Sh%RelTM and Sv%RelTM.
Higher is better on this chart. Williams has consistently been the worst on this list and has generally been at or below 0 meaning his team mates generally post better shooting percentages when not playing with Williams as opposed to playing with him. Beleskey on the other hand has always had a positive impact and Semin for the most part does as well (save for 2013-14).
Beleskey’s Sv%Rel numbers are what really got me to investigate him far more deeply. He has posted positive Sv%RelTM numbers for five straight years (2010-11 not shown) and they seem to be improving as well. Contrast that to Justin Williams who has had a negative Sv%RelTM in four of the past 5 seasons with only 2012-13 breaking that trend.
Aside: I get that people are skeptical that players can influence save percentage (I’ve seen and done the research) but I have also seen too many players show consistent trends to believe that it can’t and doesn’t happen. I have shown recently that coaches generally don’t dole out ice time based on defensive statistics which leads me to believe that it isn’t a trait that coaches emphasize. If coaches don’t emphasize it, it is understandable why not many players exhibit that skill. This would make it difficult to find league-wide correlations but it doesn’t mean that players with these skills don’t exist. It in fact could actually be a sign of untapped value.
The last couple of charts I want to present are related to point production. First lets look at 5v5 close Points/60.
What is interesting here is how much better Beleskey has been the past two seasons and how both Semin and Williams have experienced an equally significant drop off. Is aging a factor in these trends?
IPP is the percentage of goals that are scored when the player is on the ice that the player had a point (goal or an assist) on. This is an indication of how involved the player is in the offense that is being created when he is on the ice. Until this past season Williams numbers were pretty good while Semin went from OK to terrible this past season. It appears that both Semin and Williams had anomaly seasons but again, is aging a factor here. Conversely Beleskey appears to be improving and his last two seasons were very respectable, particular for a player who also seems to have good defensive numbers.
- There is ample evidence that Justin Williams possession (corsi) statistics are over inflating his value as he has fairly consistently had a poor influence on both shooting and save percentages.
- There is also ample evidence that Justin Williams is already into his declining years and giving him a longer term contract may not be wise.
- Beleskey on the other hand appears to be better overall than his possession statistics indicate and also appears to still be improving in all aspects of the game as he has entered his prime years.
- Semin once had outstanding statistics no matter what you looked at. He has shown a decline the past two seasons and last season he fell off the cliff in a number of areas statistically. At only 31 if the price was reasonable he is worth the gamble on a shorter term contract because if he can get anywhere close to where he was he’d be outstanding value.
My final thought is likely to generate some buzz and controversy amongst the analytics crowd but of the three players I believe Matt Beleskey may be the best currently and almost certainly will be the best over the next several seasons as Williams and Semin age and Beleskey continues in his prime years. There, I said it. Discuss amongst yourselves.