Sep 142013
 

A while back I came up with a stat which at the time I called LT Index which is essentially the percentage of a players teams ice time when leading that the player is on the ice for divided by the percentage of a players teams ice time when trailing that the player is on the ice for (in 5v5 situations and only in games in which the player played). LT Index standing for Leading-Trailing Index. I have decided to rename this statistic to Usage Ratio since it gives us an indication of whether players are used more in defensive situations (i.e. leading and protecting a lead and thus a Usage Ratio above 1.00) or in offensive situations (i.e. when trailing and in need of a goal and thus a Usage Ratio less than 1.00). I think it does a pretty good job of identifying how a player is used.

I then compared players Usage Index to their 5v5 tied statistics using the theory that a player being used in a defensive role when leading/trailing is more likely to be used in a defensive role when the game is tied. This is also an out of sample comparison (which is always a nice thing to be able to do) since we are using leading/trailing situations to identify offensive vs defensive players and then comparing to 5v5 tied situations that in no way overlap the leading or trailing data.

Let’s start by looking at forwards using data over the last 3 seasons and including all forwards with >500 minutes of 5v5 tied ice time. The following charts compare Usage Ratio with 5v5 Tied CF%, CF60 and CA60.

UsageRatiovsCFPct

UsageRatiovsCF60

UsageRatiovsCA60

Usage Ratio is on the horizontal axis with more defensive players to the right and offensive players to the left.

Usage Ratio has some correlation with CF% but that correlation is solely due to it’s connection with generating shot attempts for and not for restricting shot attempts against. Players we identify as offensive players via the Usage Ratio statistic do in fact generate more shots but players we identify as defensive players do not suppress opposition shots any. In fact, Usage Ratio and 5v5 tied CA60 is as uncorrelated as you can possibly get. One may attempt to say this is because those defensive players are playing against offensive players (i.e. tough QoC) and that is why but if this were the case then those offensive players would be playing against defensive players (i.e. tough defensive QoC) and thus should see their shot attempts suppressed as well. We don’t observe that though. It just seems that players used as defensive players are no better at suppressing shot attempts against than offensive players but are, as expected, worse at generating shot attempts for.

Before we move on to defensemen let’s take a look at how Usage Ratio compares with shooting percentage and GF60.

UsageRatiovsShPct

 

UsageRatiovsGF60

As seen with CF60, Usage Ratio is correlated with both shooting percentage and GF60 and the correlation with GF60 is stronger than with CF60. Note that the sample size for 3 seasons (or 2 1/2 actually) of 5v5 tied data is about the same as the sample size for one season of 5v5 data (players in this study have between 500 and 1300 5v5 tied minutes which is roughly equivalent of how many 5v5 minutes forwards play over the course of one full season).

FYI, the dot up at the top with the GF60 above 5 is Sidney Crosby (yeah, he is in a league of his own offensively) and the dot to the far right (heavy defensive usage) is Adam Hall.

Now let’s take a look at defensemen.

UsageRatiovsCFPctDefensemen

UsageRatiovsCF60Defensemen

UsageRatiovsCA60Defensemen

There really isn’t much going on here and how a defenseman is used really does’t tell us much at all about their 5v5 stats (only marginal correlation to CF60). As with forwards, defensemen that we identify as being used in a defensive are not any better at reducing shots against than defensemen we identify as being used in an offensive manner.

To summarize the above, players who get more minutes when playing catch up are in fact better offensive players, particularly when looking at forwards but players who get more minutes when protecting a lead are not necessarily any better defensively. We do know that there are better defensive players (the range of CA60 among forwards is similar to the range of CF60 so if there is offensive talent there is likely defensive talent too), and yet coaches aren’t playing these defensive players when protecting a lead. Coaches in general just don’t know who their good defensive players are.

Still not sold on this? Well, let’s compare 5v5 defensive zone start percentage (percentage of face offs taken in the defensive zone) to CF60 and CA60 (for forwards) in 5v5 tied situations.

DefensiveFOPctvsCF60

Percentage of face offs in the defensive zone is on the horizontal axis and CF60 is on the vertical axis. This chart is telling us that the fewer defensive zone face offs a forward gets, and thus likely more offensive face offs, the more shot attempts for they produce. In short, players who get offensive zone starts get more shot attempts.

DefensiveFOPctvsCA60

The opposite is not true though. Players who get more defensive face offs don’t give up any more or less shots than their low defensive zone face off counterparts. This tells me that if there is any connection between zone starts and CF% it is solely due to the fact that players who get offensive zone starts are better offensive players and not because players who get defensive zone starts are better defensive players.

You might again be saying to yourself ‘the players who are getting the defensive zone starts they are playing against better offensive players so doesn’t make sense that their CA60 is inflated above their talent levels (which presumably is better than average defensively)?  This might be true, but if zone starts significantly impacted performance (as would be the case if that last statement were true), either directly or indirectly because zone starts are linked to QoC, then there should be more symmetry between the charts. There isn’t though. Let’s look at what these two charts tell us:

  1. The first chart tells us that players who get offensive zone starts generate more shot attempts.
  2. The second chart tells us that players who get defensive zone starts don’t give up more shots attempts against.

If zone starts were a major factor in results, those two statements don’t jive. How can one side of the ledger show an advantage and the other side of the ledger be neutral? The way those statements can work in conjunction with each other is if zone starts don’t significantly impact results which is what I believe (and have observed before).

But, if zone starts do not significantly impact results, then the results we see in the two charts above are driven by the players talent levels. Knowing that we once again can observe that coaches are doing a decent job of identifying offensive players to start in the offensive zone but are doing a poor job at identifying defensive players to play in the defensive zone.

All of this is to say, NHL coaches generally do a poor job at identifying their best defensive players so if you think that guy who is getting all those defensive zone starts (aka ‘tough minutes’) are more likely to be defensive wizards, think again. They may not be.

 

Apr 122013
 

Even though I think the idea of ‘usage’ and ‘tough minutes’ is a vastly over stated factor in an individual players statistics they are interesting to look at as it gives us an indication of how a coach views the player. So for all the usage fans, here is another usage statistic which I will call the Leading-Trailing Index, or LT Index for short.

LT Index = TOI% when leading / TOI% when trailing

where TOI% is the percentage of the teams overall ice time (in games that the player played in) that the player is on the ice (so a 5v5 TOI% of 20% means the player was on the ice for 20% of the time that the team was at 5v5). Thus, the LT index is a ratio of the players ice time when his team is leading to his ice time when his team is trailing adjusted for the overall ice time that the team is leading/trailing. Any number greater than 1.00 indicates the player gets a greater share of ice time when the team is leading and anything under 1.00 indicates the player gets a greater share of ice time when the team is trailing.  So, any players with an LT index greater than one is used more as a defensive player than an offensive one and anything less than one they are used more as an offensive player than a defensive one. Any player around 1.00 is a well balanced player. So, looking at this seasons data we have the following player usage:

Defensive Usage

Defenseman LT Index Forward LT Index
MICHAEL STONE 1.21 BJ CROMBEEN 1.66
KEITH AULIE 1.20 MATHIEU PERREAULT 1.45
RYAN MCDONAGH 1.19 CRAIG ADAMS 1.35
PAUL MARTIN 1.16 TRAVIS MOEN 1.33
BRYCE SALVADOR 1.15 BOYD GORDON 1.26
BRENDAN SMITH 1.14 JAMES WRIGHT 1.26
SCOTT HANNAN 1.14 MICHAEL FROLIK 1.23
ANDREJ SEKERA 1.13 BRIAN BOYLE 1.22
MIKE WEBER 1.13 MATT CALVERT 1.22
JUSTIN BRAUN 1.12 TANNER GLASS 1.20
BARRET JACKMAN 1.12 MATT MARTIN 1.19
ROBYN REGEHR 1.12 RUSLAN FEDOTENKO 1.19
CLAYTON STONER 1.12 STEPHEN GIONTA 1.19
ANTON VOLCHENKOV 1.11 CASEY CIZIKAS 1.19
RON HAINSEY 1.11 JEFF HALPERN 1.18
TIM GLEASON 1.11 DAVID JONES 1.17
ROSTISLAV KLESLA 1.11 NIKOLAI KULEMIN 1.17
ROB SCUDERI 1.10 ZACK KASSIAN 1.17
NIKLAS HJALMARSSON 1.10 RYAN CARTER 1.16
NICKLAS GROSSMANN 1.10 TORREY MITCHELL 1.16

Offensive Usage

Defenseman LT Index Forward LT Index
RYAN ELLIS 0.78 DEREK DORSETT 0.77
KRIS LETANG 0.84 RAFFI TORRES 0.77
MARK STREIT 0.86 TAYLOR HALL 0.79
KYLE QUINCEY 0.87 CORY CONACHER 0.79
MATT NISKANEN 0.87 JORDAN EBERLE 0.80
JUSTIN SCHULTZ 0.87 NAIL YAKUPOV 0.82
DOUGIE HAMILTON 0.88 RYAN NUGENT-HOPKINS 0.82
VICTOR HEDMAN 0.88 RICH CLUNE 0.82
DAN BOYLE 0.89 BLAKE COMEAU 0.82
KEVIN SHATTENKIRK 0.89 KYLE PALMIERI 0.84
ALEX PIETRANGELO 0.89 BRENDAN GALLAGHER 0.84
JOHN-MICHAEL LILES 0.90 CLAUDE GIROUX 0.86
JOHN CARLSON 0.90 VINCENT LECAVALIER 0.86
P.K. SUBBAN 0.90 DREW SHORE 0.86
LUBOMIR VISNOVSKY 0.91 TJ OSHIE 0.87
CODY FRANSON 0.91 ALEX OVECHKIN 0.87
JAMIE MCBAIN 0.91 JONATHAN HUBERDEAU 0.87
ROMAN JOSI 0.92 NICKLAS BACKSTROM 0.87
JARED SPURGEON 0.93 SCOTT HARTNELL 0.87
CHRISTIAN EHRHOFF 0.93 MARIAN HOSSA 0.87

Balanced Usage

Defenseman LT Index Forward LT Index
MICHAEL DEL_ZOTTO 0.99 BRYAN LITTLE 0.99
ERIC BREWER 0.99 MIKE FISHER 0.99
JAKUB KINDL 0.99 MIKKEL BOEDKER 0.99
ADRIAN AUCOIN 0.99 ALEXEI PONIKAROVSKY 0.99
ALEX GOLIGOSKI 0.99 JASON POMINVILLE 0.99
ERIK GUDBRANSON 1.00 CHRIS STEWART 0.99
DREW DOUGHTY 1.00 DANIEL BRIERE 1.00
THOMAS HICKEY 1.00 RADIM VRBATA 1.00
JOHNNY ODUYA 1.00 ALEX TANGUAY 1.00
SLAVA VOYNOV 1.00 GABRIEL LANDESKOG 1.00
MATT IRWIN 1.00 JIRI TLUSTY 1.00
FRANCIS BOUILLON 1.01 COLIN WILSON 1.00
JONAS BRODIN 1.01 PATRICK DWYER 1.00
BRENT SEABROOK 1.01 JADEN SCHWARTZ 1.01
JOSH GORGES 1.01 BRANDON SAAD 1.01
DUSTIN BYFUGLIEN 1.01 LEO KOMAROV 1.01
BRENDEN DILLON 1.01 DREW MILLER 1.01
GREG ZANON 1.01 DAVID PERRON 1.01
KRIS RUSSELL 1.02 TOM PYATT 1.01

It’s amazing how much more BJ Crombeem gets used protecting a lead than when trailing. You’d have to think that score effects could have a significant impact on his stats because of this. Not really a lot of surprises there though though in the case of a guy like Derek Dorsett him being in the ‘offensive usage’ category has more with the coach not wanting to use him defending a lead than hoping he will score a goal to get the team back in the game.

 

Feb 012013
 

Last week I introduced player TOI usage charts and one use I thought they had was to look at how a players usage changed during the downside of their careers. Today I will do just that by looking at Nicklas Lidstrom’s TOI charts over the last 5 seasons. Consider this an extension to my earlier article where I took a look at Lidstrom’s last few seasons of his career. Let’s get right at it with his 5v5 chart.

LidstromTOIChart

 

Lidstrom’s last big season was clearly 2007-08 and every year since he has been below his 2007-08 levels in terms of 5v5 ice time. What is interesting to note is how little (relatively) ice time he had during the 2010-11 season, the year he won the Norris Trophy. I think it was a big mistake that he was awarded the trophy that season and this is just a little more evidence of that. In fact, Lidstrom was 4th on the Red Wings in ESTOI/Game by defensemen which is why his TOI% in the chart above were so low that year. Rafalski retired in the summer of 2011 which meant Lidstrom would get a boost to his ice time in 2011-12.

So, what about his special teams play?

LidstromPPPKTOIChart

On the powerplay, Lidstrom maintained his level of playing ~60% of his teams 5v4 power play minutes but his penalty kill ice time dropped significantly over the final 2 seasons of his career.

Based on the above charts, the last year I think you could consider Lidstrom a true heavy work load stud of a defenseman was in 2007-08. He was still awfully good for a couple more years and quite good until he retired but his slow decline in ice time had begun.