Sep 182014
 

Earlier this week TSN announced the creation of an Analytics team consisting of long-time TSN contributor Scott Cullen along with new TSN additions of Globe and Mail’s James Mirtle and hockey blogger Travis Yost. I am all for main stream media jumping on board with hockey analytics but once you go from independent hockey blogger to a significant contributor to TSN I think it opens the door to higher expectations and higher standards.  Scott Cullen has a long track record with TSN and I am confident James Mirtle will bring some intelligent insight as we are all familar with and respect his work. While I am fully aware of Yost and his blogging history I have to be honest in saying that I have not read a ton of his stuff so I was interested to see what he would offer. After reading his first two articles, I have to say I definitely think there is room for improvement.

Yost’s first article was a look at some trends as to how teams use players during 5 on 5 play. The point I think Yost was trying to make most is that teams are phasing out goons and other “specialists” and replacing them with guys that can play bigger minutes and at both ends of the rink. While this may very well be true I am not sure Yost’s evidence to support this is really valid. He produced a chart that showed that more players are getting more 5v5 ice time per game in 2013-14 than in 2007-08 and his conclusion was that this was evidence of teams moving away from goons and small ice time players.

The rightward shift here should seem apparent – a higher concentration of guys playing larger minutes now as opposed to seven years ago and fewer guys picking up scrap minutes in smaller roles. The number of forwards playing ten or less minutes a night has dropped from 109 in 2007, to 65 in 2014. And the number of forwards playing between 13 and 16 minutes a night has moved from 153 in 2007 to 231 in 2014. As a group, teams may still be leaning on their star players, but there’s also been a more balanced spread of total ice time than there was seven years ago.

First off, the rightward shift that Yost talks about is likely almost exclusively due to the fact that there were far fewer penalties and power plays in 2013-14 than there were in 2007-08 as Yost pointed out earlier. This lead to there being more even strength ice time to be doled out to the same number of players. This will almost certainly produce a right shift as observed. As for a more balanced spread in ice time, I don’t see that either. At least not to any significant extent. If one really wanted to look at this properly instead of looking at number of minutes of even strength ice time played one would want to look at percentage of a teams even strength minutes the player played. This would eliminate the difference in total even strength ice time and truly allow you to see whether teams are using a more balanced line up or not. At the very least one should adjust each players ES TOI by an appropriate amount for one of the seasons based on the ratio of league-wide ES TOI between the two seasons. I’d then be interested to see if a “right shift” occurs or whether there is a meaningful difference in the charts.

Yost’s second article for TSN.ca was about Marc-Edouard Vlasic and how he should probably be getting more recognition for how good he really is. Now that is a sentiment I can generally support but Yost’s supporting evidence for this is analytically unsound in my opinion. The first thing Yost does is identify a number of defensemen who are generally considered the leagues best that we should compare Vlasic too. This is a good start and Yost identified guys like Chara, Doughty, Karlsson, Pietrangelo, Subban, etc. What Yost did next is produce a bubble chart that plots even strength corsi% on the x-axis vs even strength goals % on the y-axis with bubble size representing scoring production. To be honest, I have no clue what the value of this chart is. Both corsi% and goal% are significantly  team driven but there was no accounting for quality of team and goal% has a certain amount of luck and randomness associated with it which was not discussed and I really have no idea what statistic was used for scoring production. The conclusion Yost drew from this chart was that Vlasic was right in the mix with some of the best defensemen in the league. Problem is I am certain I could find a number of other defensemen we generally consider mediocre that would be right there with Vlasic.

There are proper ways to do this kind of analysis and there is no way one can do this without taking into consideration quality of teammates. On my stats site I have teammate statistics (denoted by TM) and one can easily do a comparison of how the players on-ice stats compare to their teammates when their teammates are not playing with them. Doing this we get the following:

Player Name CF60 RelTM
ERIK KARLSSON 9.115
DUNCAN KEITH 8.597
ALEX PIETRANGELO 8.202
MARK GIORDANO 6.695
P.K. SUBBAN 6.152
MARC-EDOUARD VLASIC 5.87
SHEA WEBER 2.072
RYAN MCDONAGH 2.032
DREW DOUGHTY -0.448
ZDENO CHARA -0.55
RYAN SUTER -1.518

If we use CF60 as a proxy for offensive production we find the best offensive defensemen are Karlsson, Keith and Pietrangelo while the least offensive are Suter, Chara and Doughty. Vlasic is right in the middle and looks pretty good. One might be surprised at Doughty but the rest kind of make sense.

Now, let’s do the same for CA60.

Player Name CA60 RelTM
MARK GIORDANO -12.251
MARC-EDOUARD VLASIC -9.205
P.K. SUBBAN -4.586
ERIK KARLSSON -2.21
ZDENO CHARA -1.69
DREW DOUGHTY -1.585
ALEX PIETRANGELO -0.211
RYAN SUTER 0.953
DUNCAN KEITH 2.385
SHEA WEBER 4.34
RYAN MCDONAGH 4.468

For CA60 it is better to have a negative number as this indicates you are giving up fewer shot attempts than your teammates when they aren’t playing with you. Here Vlasic is second and looking pretty good.

Now we can combine these two stats by looking at CF% RelTM.

Player Name CF% RelTM
MARK GIORDANO 8.9%
MARC-EDOUARD VLASIC 6.6%
P.K. SUBBAN 4.8%
ERIK KARLSSON 4.6%
ALEX PIETRANGELO 3.7%
DUNCAN KEITH 2.3%
DREW DOUGHTY 0.7%
ZDENO CHARA 0.6%
SHEA WEBER -1.0%
RYAN SUTER -1.2%
RYAN MCDONAGH -1.2%

Out of this group, Vlasic is second best which is pretty good and is evidence that he probably deserves to be in the company of these guys. Now, with that said, this is just a cursory look and in no way a complete analysis. Not only are there limitations by just looking at corsi but there are a lot of other factors that need to be taken into consideration as well (for example, Giordano is probably not that good, only looks good because his Flames teammates are not very good relative to the teammates of the other players on this list). Overall though, this is how I think one should start an analysis of Vlasic and whether he deserves more credit for the player he is. To be fair to Yost, he gets into this a little bit by looking at a timeseries of Vlasic’s Relative Corsi% but in no way is this sufficient and he doesn’t compare it to any of the other defensemen he is comparing Vlasic to.

Overall I applaud TSN for wanting to jump on the analytics band wagon and I am certain Yost has the potential to provide a better analytical view than his first few posts which, to be honest, left me a little underwhelmed if not disappointed.

On the flip side, I saw some good stuff written recently by @MimicoHero that I think is worthy of mention. A recent blog post of his looked at Ryan Johansen’s value to the Blue Jackets and he, in my opinion, did a pretty good job of accounting for usage (i.e. QoT, QoC, zone starts) and comparing Johansen to his peers. I like the tables he produced and how he looked at offense and defense separately. Now I’d probably want to weight QoT far more heavily in the usage metric he came up with but overall a very good methodology for comparing players on different teams playing in different circumstances.

 

Aug 092014
 

The other day over at PensionPlanPuppets.com there was a post by Draglikepull looking at zone exits by Maple Leaf defensemen for the first half of last season. If you haven’t seen it yet, definitely go read it. I wanted to compare the zone exit data to my rush shot data which I have calculated from play by play data as explained here. If we can find good correlations between zone entry/exit data and my rush shot data that would be an excellent finding because the zone entry/exit data need to be manually recorded and is very time consuming. Thankfully this is a project being undertaken by Corey Sznajder. If we can find useful correlations with data that can be automatically calculated we may not need to do this in the future and Corey can have a summer vacation next year.

Let’s first look at defensive zone exit percentage and how it correlates with rush and non-rush shots.

PlayerName RushCF/60 Non-Rush OtherCF/60 Exit%
MORGAN RIELLY 11.5 39.8 27.5
CARL GUNNARSSON 10.6 35.1 25.9
DION PHANEUF 10.1 37.9 25.5
JAKE GARDINER 11.2 37.7 24.8
JOHN-MICHAEL LILES 15.5 41.9 24
CODY FRANSON 10.5 36.9 23.8
PAUL RANGER 12.0 32.9 20.5
MARK FRASER 14.5 34.7 13.3

One thing to note is that my rush shot data is for the full season and the exit% data is for the first half of last year. Also, my rush shot data is only road data to eliminate arena bias and Liles and Fraser also includes their time with Carolina and Edmonton respectively.

Let’s look at some charts to more easily see if a correlation exits.

 

Leafs_dmen_DefZoneExitPct_vs_RushShotsFor

Ok, this is very counter-intuitive. The defensemen that have the best defensive zone exit percentage have a lower rush shot rate and a higher non-rush shot rate. On the surface this doesn’t make sense. If you are better at carrying the puck out of your own zone you should be able to generate more shots from the rush but that doesn’t seem to be the case. I think what is actually happening here is that to be able to carry the puck out of the defensive zone you have to be a skilled puck handler and if you are skilled with the puck you probably get more time in the offensive zone including more offensive zone starts and more ice time with offensive type forwards. Now, if you are not a good offensive defenseman you probably don’t get many offensive zone starts and get more defensive zone starts and maybe more importantly you play less with offensive minded forwards.

It should also be noted that Fraser is a bit of an anomaly here as his defensive zone exit percentage is well below anyone else’s and his rush shot rate is quite good. If we take Fraser out of the charts the relationship is much flatter and the correlations get weaker. We need to look at more defensemen to get more conclusive results though. Also, I think we will also find that we will get better results for forwards as I generally think it is forwards that drive the offense, not the defensemen.

Another factor in the non-relationship between defensive zone exits and rush shots for might be that often when a team exits the defensive zone they conduct a line change and maybe in particular a change in defensemen as the forwards are taking the puck up the ice. Defensemen may be able to get the puck out of their own end and initiate a rush but are on the bench before the benefits of the zone exit and follow-up rush have materialized. This could result in the lack of positive correlation between zone exits and rush shots. I need to create an “initiator of rush shots” statistic to account for this possibility.

In the comments of the pensionplanpuppets.com article Corey Sznajder provided statistics on  zone entries against each defenseman. Most defensemen would likely have significantly more control over zone entries against than they do for creating offense so we might find stronger correlations here.

PlayerName RushCA/60 OtherCA/60 Carry% Against Break-up %
MARK FRASER 18.9 44.2 71.4 7.1
JAKE GARDINER 14.9 42.4 67.7 6
MORGAN RIELLY 16.1 49.4 67.7 4.3
CARL GUNNARSSON 13.1 56.4 64.4 11.3
CODY FRANSON 14.8 46.6 64.1 5.7
JOHN-MICHAEL LILES 10.5 45.2 55.2 6.9
PAUL RANGER 14.8 49.2 54.7 17.4
DION PHANEUF 13.7 58.1 53.1 13.4

 

Leafs_dmen_RushShotsAgainst_vs_CarryInPctAgainst

Now this is a little closer to what we might expect. Those defensemen that have a high percentage of zone entries against being carry-in entries vs dump-ins give up rush shots at a higher rate while also giving up non-rush shots at a lower rate. There doesn’t appear to be any correlation between Carry In % Against and total corsi against per 60 (r^2=0.026) so it seems only the type of shot against is being impacted. I have observed that shots on the rush are significantly more difficult shots (shooting percentage on rush shots over last 7 seasons has been 9.56% vs 7.34% on non-rush shots making rush shots 30% more difficult on average) so players that can limit the frequency of carry-in rushes against and force dump-ins against instead are in fact likely to reduce average shot difficulty against.

The real counter-intuitive observation is that from a strategy/tactics point of view, it might be better to start your defensive defensemen (i.e. the ones that have the ability to limit rushes against) in the offensive zone (for the Leafs this would be Phaneuf  and Liles/Gleason last year) and start your strong offensive and weak against the rush defensemen (i.e. Rielly, Gardiner in particular) in the defensive zone . This is the opposite of what the Leafs did last season and generally opposite of what most normally consider doing. It makes sense though. When you are in your own zone you want defensemen who can get the puck and get it out and when you are in the oppositions zone you want defensemen who don’t give up high quality (often odd-man) rushes against. Defense should start in the offensive zone and offense should start in the defensive zone. The focus is generating offense on the rush and limiting the other teams ability to generate offense on the rush. It’s a bit counter-intuitive but might prove to be smart strategy.

I look forward to when the zone entry/exit tracking project gets completed and we can look at a much larger sample with more players from more teams but between that project and the rush shot data I have calculated we should gain significantly more insight into the game and how it is played. We might even come up with some new revolutionary on-ice strategies.

 

Jul 022014
 

The other day I looked at the effect that Mike Weaver and Bryce Salvador had on their teams save percentage (if you haven’t read it, definitely go give it a read) when they were on the ice versus when they weren’t on the ice. Today I am going to take a look at the Maple Leaf defensemen to see if there are any interesting trends to spot. We’ll start with the new acquisitions.

Stephane Robidas

RobidasOnOffSavePct

(Blue line above orange is good in these charts, opposite is not good)

Aside from 2008-09 he has had a negative impact on his team save percentage. In 2007-08, 2009-10 and 2010-11 his main defense partner was Nicklas Grossman but in 2008-09 his main defense partner was Trevor Daley. Did this have anything to do with his poor effect on save percentage in 2008-09? Well, aside from last season Daley’s on-ice save percentage has been at or better than the team save percentage so there might be something to that.

Roman Polak

PolakOnOffSavePct

Not really a lot happening there except in 2011-12 when he was worse than the team (and the team had significantly better goaltending). Rembember though, the Blues have a pretty good defense so it is quite possible that not being worse than the rest of them is a good thing. Will be interesting to see how he does in a Leaf jersey this season.

Dion Phaneuf

PhaneufOnOffSavePct

Aside from 2008-09 there has been a slight positive impact on save percentage when he is on the ice. In 2008-09 he didn’t have a regular defense partner. At 5v5 he played a total of 1348:08 in ice time and his main defense partners were Giordano (364:56), Vandermeer (342:47), Pardy (304:27), Leopold (163:47), Regehr (85:08) and Sarich (77:41). That variety in defense partners can’t be a good thing. But, maybe Phaneuf has a slight positive impact on save percentage.

Cody Franson

FransonOnOffSavePct

So, he was good for a few years and then he was bad. What happened? Well, he was traded to the Leafs. For the 2009-10 and 2010-11 seasons his main defense partner was Shane O’Brien and he also spent significant time with Hamhuis. This could be a case of him playing “protected” minutes as he had really easy offensive QoC but I generally don’t think QoC has anything near as significant an impact as other factors so I am not sure what is going on. He has had pretty weak QoC the last couple seasons too so who knows.

Jake Gardiner

GardinerOnOffSavePct

It is only 3 seasons of data but so far so good for Gardiner. He has been a boost to the teams save percentage and that is on top of his good possession numbers. In my opinion, Gardiner is quite likely the best defenseman. I’ll drop the “quite likely” from that statement when he repeats his success but against tougher QoC as that will remove any doubt.

Now, let’s take a look at a couple of departing Leaf defensemen.

Carl Gunnarsson

GunnarssonOnOffSavePct

Save for 2010-11 Leaf save percentage has been better whith Gunnarsson on the ice. His two main defense partners that year were Luke Schenn and Mike Komisarek so maybe we can forgive him. In 2009-10 his defense partner was mainly Beauchemin or Kaberle and starting in 1011-12 it has mainly been Phaneuf.

Tim Gleason

GleasonOnOffSavePct

Tim Gleason gets a lot of criticism from Leaf fans, the analytics community, and maybe pretty much everyone but his teams have generally had a positive boost in save % when he is on the ice and in some cases a significant boost.

Based on the loss of Gunnarsson and Gleason, two defenseman who seem to be able to boost on-ice save percentage, and the addition of Robidas who has a negative impact and Polak who has more neutral impact it is quite possible the Leafs suffer a drop off in save percentage this season.

That said, I am not certain what to make of the impact we see and why they occur. Of the 9 defenseman I have presented charts for the past few days (the 7 above as well as Weaver and Salvador in my previous post) it seems that the majority of them have all but one or two of their seasons consistently boosting or inhibiting their teams save percentage. More investigation is needed as to why but I am becoming fairly confident that this is a repeatable talent. There is just too much consistency to consider it purely random.

 

Jan 262012
 

With the re-signing of John-Michael Liles the Leafs now have an abundance of defensemen signed under control for a number of years, many with big dollar contracts too.  We all have our varying opinions on the relative values of each of these defensemen but I thought it would be an appropriate time to take a closer look at them statistically.

Offensively

2011-12 HARO+ 2010-11 HARO+ 2010-12 HARO+ 2011-12 FenHARO+ 2010-11 FenHARO+ 2010-12 FenHARO+
JOHN-MICHAEL LILES 1.23 1.03 1.11 0.96 0.99 1.00
CODY FRANSON 1.20 1.06 1.10 1.05 1.05 1.03
LUKE SCHENN 1.10 1.08 1.08 0.85 1.02 0.99
DION PHANEUF 1.01 1.08 1.05 1.00 0.99 1.03
CARL GUNNARSSON 1.05 1.00 1.02 1.04 0.92 0.94
MIKE KOMISAREK 1.10 0.96 1.00 1.02 0.90 0.86
KEITH AULIE 0.90 1.02 0.99 0.78 0.86 0.89
JAKE GARDINER 1.18 0.94

The above list are my own offensive ratings (goal based and fenwick based) for 5v5 zone start adjusted (10 seconds) situations sorted by their year and a half (2010-12) HARO+ ratings.

The list generally fits with what we might expect though the one surprise is probably Luke Schenn being rated so highly offensively.  I had a debate with a few people last week where I suggested that Schenn is as good offensively as Phaneuf and got ridiculed for making that statement but the numbers do in fact support that.  The above are based on ‘on-ice’ numbers but individual stats make Schenn look good too.  This season Phaneuf has 2 even strength goals and 13 even strength points while Schenn has 1 even strength goal and 11 even strength points but Phaneuf has played more than 30% more even strength minutes than Schenn.  Last season Phaneuf had 5 goals and 17 points at even strength versus Schenn’s 5 goals and 21 points in 20% more minutes.  Combined Schenn has 6 goals and 32 points in 2237 ES minutes while Phaneuf has 7 goals and 30 points in 2207 ES minutes.  That’s awfully close offensive production if you ask me.  The difference in their overall totals is solely due to Phaneuf’s PP minutes and Schenn’s lack of them.

Getting back to the rest of the team, it is no surprise to see Liles and Franson at the top of the list.  They are known to be more offensive specialists and the stats bear that out.  The reverse is true for Komisarek and Aulie who are viewed as more defensive defensemen and that is the role they are assigned.  They simply do not produce much offense.  We only have half a season of Jake Gardiner, but so far so good.  While his fenwick offensive numbers aren’t crazy good, his HARO+ rating is very very good.  I think Gardiner is someone we can be cautiously optimistic will develop into a very good (maybe Liles-like) offensive defenseman.

For interest sake, here are the players raw offensive numbers for the last 2 seasons combined sorted by GF20.

2010-12 GF20 2010-12 FF20
LUKE SCHENN 0.88 12.62
CODY FRANSON 0.88 13.22
JOHN-MICHAEL LILES 0.87 12.66
DION PHANEUF 0.85 13.01
CARL GUNNARSSON 0.83 11.96
MIKE KOMISAREK 0.81 11.00
KEITH AULIE 0.81 11.41

Gardiner’s GF20 is 0.96 and FF20 is 12.62 so far this season.

Defensively

This is the defensive equivalent of the above offensive rating chart.

2011-12 HARD+ 2010-11 HARD+ 2010-12 HARD+ 2011-12 FenHARD+ 2010-11 FenHARD+ 2010-12 FenHARD+
CODY FRANSON 0.77 1.39 1.15 1.02 0.98 1.00
KEITH AULIE 0.71 1.22 1.05 0.89 0.87 0.85
DION PHANEUF 0.87 1.07 1.00 1.04 0.94 0.97
CARL GUNNARSSON 1.04 0.86 0.95 1.00 0.94 0.99
LUKE SCHENN 0.83 0.88 0.88 0.89 0.93 0.90
JOHN-MICHAEL LILES 0.85 0.86 0.87 1.00 1.00 0.99
MIKE KOMISAREK 0.78 0.74 0.76 0.90 0.93 0.95
JAKE GARDINER 0.94 0.97

There are definitely some surprises in the above list and there are probably some small sample size issues going on.  Franson looked awesome defensively last season but terrible this season when considering their goal based HARO+ numbers.  The same is true for Aulie, and to some extent Phaneuf while the reverse is true for Gunnarsson.  For each of them their Fenwick numbers are a little more consistent.

All-in all though, Franson looks like he could be a more than respectable defenseman defensively.  His fenwick ratings are pretty solid and his 2-year goal ratings are very good.  On the other side of the spectrum, Komisarek looks awful, regardless of whether you consider goal ratings or fenwick ratings.  This is not good for a guy who doesn’t produce offense either.  Luke Schenn’s defensive numbers are a little better than Komisarek’s but still not great, but at least he is producing offensively.

Again, for interest sake, here are each defenseman’s 2-year raw defensive numbers.

2010-12 GA20 2010-12 FA20
CODY FRANSON 0.67 13.06
KEITH AULIE 0.73 15.36
DION PHANEUF 0.78 13.48
CARL GUNNARSSON 0.83 13.30
LUKE SCHENN 0.88 14.51
JOHN-MICHAEL LILES 0.92 13.05
MIKE KOMISAREK 1.02 13.75

Gardiner’s GA20 is 0.80 and FA20 is 13.83 so far this season.

Contract Status and Moving Forward

Phaneuf and Komisrek are signed for 2 more seasons at $6.5M and $4.5M cap hits respectively.  Liles and Schenn are signed for 4 more seasons each at $3.875M and $3.6M cap hits respectively.  Carl Gunnarsson is signed for another season at $1.325M when he becomes an RFA and will be due a substantial raise.  Cody Franson is set to become an RFA this summer and will deserve a sizeable raise from his current $800K salary.  Jake Gardiner has 2 years left on his entry level deal with a $1.1M cap hit and Keith Aulie is an RFA this summer.  The Leafs also have Korbinian Holzer, Jesse Blacker and others in the farm system ready to make a push for a roster spot on the Leafs in the next year or two.

The Leafs salary cap hit for their defensemen next season will be $21M plus whatever Cody Franson gets on a new contract which quite likely will be around the $1.5-2.5M range.  That would bring their expenditures on defensemen to $23M which actually isn’t all that ridiculous if the salary cap is $65+M.  That said, if they are looking to free up salary to spend on forwards and/or are looking to open up a roster spot for their young defensemen there are a few options.

The first option is to trade (if possible) Mike Komisarek.  He provides no real value to this team but then he will probably provide no value to any team so trading him might be difficult.  He also has a limited no trade clause limiting the number of potential trade partners as well.  He would be a perfect candidate to have his contract buried in the AHL (in actual dollars he’ll earn $3.5M in each of the next 2 seasons and coincidentally Jeff Finger’s buried $3.5M contract expires this summer) but he has a no movement clause which means he cannot be demoted.  The only option to get his contract off the books is via trade.

Another option is to trade Luke Schenn.  He provides some value to the Leafs with his offensive ability but that is not an area where the Leafs are lacking (most of their defensemen have offensive capabilities).  His poor defensive numbers make him expendable in my opinion and being young and on a reasonably priced long term contract he should have a lot of value on the trade market.  He could feasibly be used in a package to land the Leafs the big two-way forward they desperately need.

The other options are trading either Franson or Gunnarsson.  Neither would save the team as much cap space as either Komisarek or Schenn but both would have good value on the trade market.  That said, I would not be a proponent of this as I think they both provide good value to the Leafs, and are likely to provide good value for many years.  Gunnarsson has developed into a solid all-purpose defenseman and I think Franson has that ability too.