May 07 2012 04:57PM
Measuring a player’s defensive contributions statistically is currently one of the most difficult things to do. You can’t just look at goals (or shots) against, because the great defensive players are up against the toughest opponents and in their own end, while the weaker ones are against softer opponents mostly in the opposing zone. Calculating for this is very challenging and even if you could, is there really a way to compare how effectively a player in one situation did relative to someone in another?
Many people have tried to create catch-all statistics, like Tom Awad’s Goals Versus Threshold (GVT), Iain Fyffe’s Point Allocations, Alan Ryder’s Player Contributions (PC) and Justin Kubatko’s Point Shares (PS), to name just a few. And while they’re a step up on plus/minus (or even Corsi, which is a shot-based plus/minus statistic), they leave a lot to be desired, often leading to crazy conclusions like Anton Babchuk is Robyn Regehr’s defensive equal, as we explored earlier this year.
Regardless of the shortcomings of the existing systems, it’s still worthwhile to look back and see how the Flames stack up against one another defensively. We’ll also look at Vollman’s Folly, a name hastily applied to a system we designed to prove that a better catch-all defensive statistic was possible, something it was never intended to actually be.
Vollman's Folly works by figuring out how many shots a team prevented relative to the 1992-93 San Jose Sharks (a replacement-level team defensively), and assigning credit to the players relative to the amount of defensive ice-time they played, which was crudely estimated based on their special teams usage.
Let’s start with the defensemen.
Flames 2011-12 Defensemen
Both the Defensive Point Shares system and Vollman’s Folly correctly concluded that Jay Bouwmeester was Calgary’s best defensive player, but Defensive GVT incorrectly gave Scott Hannan a huge nod. This was basically the only point of contention between DPS and DGVT, which otherwise agreed completely.
Defenseman GP DPS VF DGVT Scott Hannan 78 3.0 62.0 5.1 Jay Bouwmeester 82 4.8 64.1 3.8 Mark Giordano 61 3.4 27.8 3.6 Chris Butler 68 2.8 55.1 3.2 Cory Sarich 62 2.5 37.9 2.3 T.J. Brodie 54 2.4 10.0 2.1 Derek Smith 47 1.7 9.3 1.2 Anton Babchuk 32 1.3 4.8 0.9
Is Mark Giordano Calgary’s 2nd best defensive option on the blue line? If so you’re probably happy with DGVT, and if you even believe he’s Bouwmeester’s equal then you’re probably happy with DPS because his 3.4 DPS in 61 games would work out to 4.6 over Bouwmeester’s 82.
On the other hand if you believe Mark Giordano is a much improved and underrated defensively but doesn’t contribute quite as much in his own end as Calgary’s other top-four defensemen Scott Hannan and Chris Butler, then VF might be worth a closer look.
Otherwise the only bone of contention could be among the depth defensemen. While DPS and DGVT see Cory Sarich and T.J. Brodie as basically equivalent and only a short step below Chris Butler, VF has Sarich up ahead of Giordano, and Brodie in the back of the pack with Derek Smith and Anton Babchuk.
Now, let’s see what the picture is like up front.
Jarome Iginla as Calgary’s 2nd best defensive forward? That’s how DPS sees it. Fortunately DGVT adds a bit more sanity to the picture where Calgary’s beloved captain barely edges out Matt Stajan and Roman Horak for 6th.
Forward GP DPS VF DGVT Alex Tanguay 64 1.9 11.9 3.4 Curtis Glencross 67 1.0 20.9 2.7 Lee Stepmniak 61 1.2 14.3 2.1 Olli Jokinen 82 1.5 11.7 1.9 Tom Kostopoulos 81 0.6 25.7 1.8 Jarome Iginla 82 1.7 11.8 1.6 Matt Stajan 61 0.9 18.0 1.5 Roman Horak 61 0.9 6.0 1.5 David Moss 32 0.4 9.2 1.3 Blake Comeau 74 1.0 25.5 1.2 Blair Jones 43 0.5 8.2 1.1 Mike Cammalleri 66 1.1 10.5 1.0 Paul Byron 22 0.4 1.9 0.7 Mikael Backlund 41 0.2 9.7 0.2 Lance Bouma 27 0.1 6.9 0.1 Krys Kolanos 13 0.1 1.0 0.1 G. Desbiens 10 0.0 0.6 -0.3 Tim Jackman 75 0.0 5.5 -0.8
Alex Tanguay is Calgary’s best defensive forward, at least according to both DPS and DGVT, which certainly makes more sense than VF’s assertion (Tom Kostopoulos, who probably didn’t play a regular shift against a 20-goal scorer at even-strength all season). While he played a slightly tougher role, the same thing could be said for Blake Comeau, who comes in 2nd.
Curtis Glencross is probably the team’s actual best defensive forward, based on people’s subjective opinions, as well as Sutter’s choice to use him against top opponents and on the first penalty-killing unit. He’s ranked 2nd by DGVT, 3rd by VF, and 6th by DPS.
DGVT could very well be the winner here, not just for ranking Curtis Glencross so highly and for avoiding overestimation of Iginla, Kostopoulos and Comeau, but for wisely ranking Lee Stempniak 3rd just ahead of Olli Jokinen.
Defensive GVT did a surprisingly good job ranking Calgary’s players defensively, except for overestimating Scott Hannan (or underestimating Jay Bouwmeester). The top forward ranking of Alex Tanguay, Curtis Glencross, Lee Stempniak, Olli Jokinen and Tom Kostopoulos all ahead of Jarome Iginla, Matt Stajan and Roman Horak seems quite reasonable.
Defensive Point Shares may have placed Jay Bouwmeester on top, but overestimated Mark Giordano, left the defensemen in far too tight a pack, and made a complete mess of the forwards.
The simplistic Vollman’s Folly system underestimated Mark Giordano, overestimated Cory Sarich, and placed depth options Blake Comeau and Tom Kostopoulos ahead of legitimate top-line shadows like Curtis Glencross.
A usable catch-all defensive statistic might be further from our grasp than we had hoped, but in the case of the Calgary Flames defensive GVT is certainly getting closer.