# 2005-06 NHL Goal Differentials

Discussion in 'By The Numbers' started by Doctor No, May 21, 2006.

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1. ### Doctor NoRegistered User

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A little preview of something I've been working on.

The premise of this exercise is simple - how many goals above average did a particular NHL goaltender prevent in the 2005-06 National Hockey League?

It's a very straightforward calculation:

Suppose that the "league average" goaltender stopped exactly 90% of shots
faced.

Suppose that Goalie X allows 80 goals on 1000 shots (92% saves on shots faced). On 1000 shots, a "league average" goaltender would allow 100 goals.

Therefore, Goalie X has a goal differential (relative to the league) of 20 goals.

One benefit of this analysis, when compared to save percentage, is that it is league-neutral. A goaltender who stops 92% of shots in 2003-04 (when the league save percentage was 91.1%) is much more average than one who stops 92% of shots in 1988-89 (when the league save percentage was 87.9%).

Another benefit is that it gives more value to a good goaltender who plays a lot. If you're stopping 92% of shots faced, but only playing one game, you're not helping your team as much as someone who stops 92% of shots in sixty games.

Notes - there are obvious deficiencies with this method. Most prominently, it's a transformation of save percentage, and therefore carries all of the disadvantages of save percentage.

Code:
```[font=courier new]
[B]GOALTENDER      TEAM     GD[/B]
Kiprusoff        CGY  41.60
Vokoun           NSH  35.86
Luongo           FLO  32.62
Lundqvist        NYR  30.60
Huet             MON  30.11
Fernandez        MIN  29.14
Hasek            OTT  28.66
Brodeur          NJD  20.81
Thomas           BOS  18.75
Miller           BUF  18.16
Giguere          ANA  17.03
Legace           DET  16.81
Leclaire         CBJ  10.01
Roloson          [I][COLOR=DimGray]MIN   6.93
EDM   2.06[/COLOR][/I]
TOTAL   8.99
Gerber           CAR   7.70
Aubin            TOR   7.58
Toivonen         BOS   7.25
Mason            NSH   6.94
Sanford          STL   6.37
Bryzgalov        ANA   6.36
Lehtonen         ATL   4.86
Biron            BUF   3.75
Johnson          WSH   3.31
Schaefer         SJS   2.62
Auld             VAN   2.32
McLennan         FLO   1.54
Emery            OTT   1.16
Danis            MON   1.01
Joseph           PHO   0.84
Howard           DET   0.27
Holt             NYR   0.20
Harding          MIN   0.19
Sigalet          BOS   0.00
McVicar          VAN   0.00
Rinne            NSH  -0.05
Coleman          TBL  -0.32
Toskala          SJS  -0.32
Dubielewicz      NYI  -0.69
Budaj            COL  -0.71
Crawford         CHI  -0.95
Cassivi          WSH  -1.04
LaBarbera        NYR  -1.08
Eklund           TBL  -1.12
Bacashihua       STL  -1.16
Hedberg          DAL  -1.40
Munro            CHI  -1.90
Denis            CBJ  -2.43
Kolesnik         COL  -2.43
DiPietro         NYI  -2.60
Sabourin         PIT  -2.62
Dunham           ATL  -2.83
Finley           NSH  -2.95
Cloutier         VAN  -3.03
Osgood           DET  -3.26
Aebischer        [I][COLOR=DimGray]COL  -1.28
MON  -2.31[/COLOR][/I]
TOTAL  -3.59
Hauser           LOS  -3.63
Prusek           CBJ  -3.71
Tellqvist        TOR  -4.19
Esche            PHI  -4.51
Burke            TBL  -4.58
Berkhoel         ATL  -4.83
Fleury           PIT  -5.40
Weekes           NYR  -5.41
Turco            DAL  -5.68
Clemmensen       NJD  -5.88
LeNeveu          PHO  -5.89
Shields          ATL  -6.27
Sauve            [I][COLOR=DimGray]CGY  -2.06
PHO  -4.36[/COLOR][/I]
TOTAL  -6.42
Noronen          [I][COLOR=DimGray]BUF  -4.40
VAN  -2.40[/COLOR][/I]
TOTAL  -6.80
Conklin          EDM  -7.56
Niittymaki       PHI  -8.02
Morrison         [I][COLOR=DimGray]EDM  -6.36
OTT  -2.52[/COLOR][/I]
TOTAL  -8.88
Snow             NYI  -9.26
Kolzig           WSH  -9.84
Garnett          ATL -10.41
Anderson         CHI -11.27
Boucher          [I][COLOR=DimGray]PHO  -6.54
CGY  -4.83[/COLOR][/I]
TOTAL -11.37
Thibault         PIT -12.22
Belfour          TOR -13.29
Garon            LOS -13.42
Divis            STL -14.20
Caron            PIT -14.64
Ward             CAR -14.69
Lalime           STL -17.31
Grahame          TBL -17.86
Nabokov          SJS -18.48
Raycroft         BOS -18.65
Markkanen        EDM -18.82
Khabibulin       CHI -20.86
Theodore         [i][COLOR=DimGray]MON -20.81
COL  -1.87[/COLOR][/i]
TOTAL -22.68
[/font]```

2. ### Doctor NoRegistered User

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Leaders year-by-year (to give you an idea of relative levels of dominance):
Code:
```[font=courier new]
1982-83 Pete Peeters (BOS)         42.23
1983-84 Rollie Melanson (NYI)      32.71
1984-85 Pelle Lindbergh (PHI)      47.87
1985-86 Kelly Hrudey (NYI)         45.92
1986-87 Ron Hextall (PHI)          41.88
1987-88 Tom Barrasso (BUF)         26.23
1988-89 Patrick Roy (MON)          35.09
1989-90 Patrick Roy (MON)          47.15
1990-91 Ed Belfour (CHI)           44.63
1991-92 Patrick Roy (MON)          46.99
1992-93 Curtis Joseph (STL)        57.42
1993-94 John Vanbiesbrouck (FLO)   55.62
1994-95 Dominik Hasek (BUF)        36.42
1995-96 Dominik Hasek (BUF)        43.29
1996-97 Dominik Hasek (BUF)        54.41
1997-98 Dominik Hasek (BUF)        54.12
1998-99 Dominik Hasek (BUF)        54.08
1999-00 Olaf Kolzig (WSH)          24.11
2000-01 Sean Burke (PHO)           32.84
2001-02 Jose Theodore (MON)        45.91
2002-03 Marty Turco (DAL)          31.89
2003-04 Roberto Luongo (FLO)       47.52
2005-06 Miikka Kiprusoff (CGY)     41.60
[/font]```

3. ### LowetideRegistered User

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This is terrific stuff. Thanks.

4. ### Doctor NoRegistered User

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Definitely my pleasure! I'll put more up once my fingers recover - and, of course, it'll all end up on my website eventually (it's going to be a long summer )

5. ### Doctor NoRegistered User

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Top twenty careers (1982-83 to present):

Note that save percentage was not made official until 1982-83; hence, seasons prior to this are not considered.

Extra note - the difference between Roy/Hasek and the rest of the goaltenders is phenomenal.

Code:
```[font=courier new]Patrick Roy               429.91
Dominik Hasek             392.49
John Vanbiesbrouck        192.94
Curtis Joseph             188.58
Ed Belfour                165.20
Martin Brodeur            152.61
Roberto Luongo            133.69
Kelly Hrudey              125.13
Andy Moog                 111.89
Guy Hebert                108.85
Mike Richter               92.17
Tom Barrasso               87.89
Bob Froese                 83.50
Sean Burke                 80.63
Ron Hextall                77.19
Pete Peeters               76.72
Rejean Lemelin             76.57
Glen Hanlon                73.02
Billy Smith                71.42
Daren Puppa                71.38
[/font]```

6. ### Doctor NoRegistered User

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And the ten worst, for those of you who gawk at car accidents on the highway:

Code:
```[font=courier new]
Craig Billington          -151.08
Alain Chevrier             -96.49
Kirk McLean                -87.01
Peter Sidorkiewicz         -81.21
Richard Brodeur            -80.40
Bill Ranford               -71.61
Ken Wregget                -65.92
Greg Stefan                -65.51
Daren Eliot                -63.01
Tim Cheveldae              -62.42
[/font]```

7. ### Hockey OutsiderRegistered User

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Great work. I definitely appreciate the time/effort necessary to make lists like these.

I have a similar formula that I've used for a while. (So does Tom Awad, who beat us both by several years). I made a couple of minor adjustments (which were more important for the Original Six era--you can find those stats in Klein & Reif's "Hockey Compendium") but the basic premises are the same. Despite some adjustments, the results you posted are very similar to what I had. Great minds think alike.

It would be interesting if you could post a list with the highest peak value (ie a goalie's best rating over five consecutive years).

With that said, I'm sure you'll get flamed within a few posts, claiming your formula overrates certain players or underrates others, or the all-purposeful "stats mean nothing!"

Last edited: May 21, 2006
8. ### Doctor NoRegistered User

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Thanks! I enjoy Tom's work - I hadn't seen this come across the research list from him, but I sometimes miss posts on there so it's not surprising that I missed it. I'll have to hit the archives.

I think that I can pull out peak value - I'll check into it.

On your changes, did you remove the goaltender's statistics from the league average before doing the calculations? (I didn't, but it's defensible and would obviously make a greater impact in Original Six seasons).

I'm a huge K&R fan - my happiest moment involving hockey statistics was when they mentioned me on page 234 of their second edition. (I wore out my library's copy of their first edition, and I was kinda worred that they would get upset that I continued Perseverance Rating after their publication date )

9. ### InjektiloRegistered User

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Man, this really shows what a gong show Edmonton's goaltending was before Roloson.

10. ### Snap WilsonRegistered User

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I did this exact same thing several years ago.

Doctor No, list the best single seasons of all-time. I know Theodore's Hart season and Cujo's '93 season rank up there.

11. ### RandRegistered User

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Cujo

12. ### Doctor NoRegistered User

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Bumping this because I'm going to mention it in the Fuhr discussion over there (points that way).

13. ### vbet*Guest

Kipper was just amazing last year. He made more big saves than any goalie I've every watched include all my years of being a season ticket holder watching fuhr back in the early 80's.

I still find it amazing he smokes. But it does get him his own room on the road.

14. ### BajahoboRegistered User

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Craig tried his best, damn it.

15. ### Doctor NoRegistered User

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Miikka was dominant last year, to be sure. As an Avs fan, it was fun/scary to go into that building knowing that he was in net.

I just realized that I need to put the 2006 playoff numbers up here - since they obviously weren't done in mid-May when I originally posted this.

16. ### DwightThe French Tickler

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17. ### Doctor NoRegistered User

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I'm one of the biggest Billington fans there is. He was hamstrung by some pretty bad Ottawa teams, with correspondingly low save percentages.

One of the deficiencies of this method - as I mentioned in the original post - is that save percentage is not perfect (and if you don't like save percentage, this isn't going to fix it).

Once better shot data is available, I have methods in place to risk-adjust each shot with respect to location, type, and manpower situation (all things save percentage ignores). Unfortunately, that won't save Craig's totals unless someone goes back and watches every Billington game (and every shot he faces).

18. ### BajahoboRegistered User

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It's been done in baseball in regards to fielding metrics (albeit to contested results). I'm sort of surprised it hasn't been tried in hockey.

edit: You should do one of these just taking into consideration the playoffs and major international competition (WC, Olympics).

19. ### Doctor NoRegistered User

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I've done playoffs, and I could easily do WC and Olympics with the data I have on my site. I'll start posting stuff this weekend!

20. ### BajahoboRegistered User

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And if you're going back to the early 80s you might as well include the Canada Cup.

(demanding when I don't have to do the work aren't I?)

21. ### Doctor NoRegistered User

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Here's the 2006 Stanley Cup playoffs. Comments to follow.

Code:
```[font=courier new]
[B]GOALTENDER     TEAM         GD[/B]
Roloson        EDM       13.25
Bryzgalov      ANA       10.86
Ward           CAR        8.05
Huet           MON        4.98
Brodeur        NJD        4.60
Kiprusoff      CGY        1.53
Toskala        SJS        1.31
Miller         BUF        1.20
Clemmensen     NJD        0.28
Markkanen      EDM       -0.09
Nabokov        SJS       -0.62
Conklin        EDM       -0.72
Mason          NSH       -0.88
Theodore       COL       -1.10
Burke          TBL       -1.63
Weekes         NYR       -1.64
Emery          OTT       -1.76
Niittymaki     PHI       -2.27
Legace         DET       -3.39
Gerber         CAR       -4.52
Turco          DAL       -5.18
Esche          PHI       -5.41
Lundqvist      NYR       -5.55
Giguere        ANA       -5.56
Grahame        TBL       -5.76[/font]```

22. ### Doctor NoRegistered User

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One thing I should mention before I continue - just because a goaltender rates as "negative" (below average) in any of these ratings, that does not mean that they are not valuable.

By definition, half of NHL goaltenders must be "below average". Since NHL talent can be approximated as the right-end tail of a normal distribution, an "average NHL goaltender" is still quite good.

Roloson's 13.25 speaks largely - if the Oilers had won the Stanley Cup, he would have been a solid Conn Smythe candidate despite being injured in Game One of the Finals.

What surprised me most about these were Ilya Bryzgalov's totals - he was nearly one goal per game above average in his Cup playoffs.

Cristobal Huet almost matched this feat, albeit in just six games.

Ty Conklin's totals might not stand out until you remember that his play was worth -0.72 goals to the Oilers in just six minutes of action.

John Grahame takes the tail end of these, costing the Lightning nearly six goals in less than four full games.

How much did Hasek's injury cost the Senators? If we extrapolate his regular season statistics to the 2006 Ottawa playoffs, he would be worth 6.70 goals above average. Ray Emery totalled 1.76 goals below average.

That's about 0.85 goals per game Hasek would have stopped over Emery (under these assumptions, of course). Would that have made a difference in the Buffalo series?

23. ### Superfluous URegistered User

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You could do GDA per game. He'd stand out as a rate!

24. ### fastbRegistered User

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What a surprise, Thibault and Caron were in the very bottom of the list. But who'd have guessed that Caron would actually rate worse than Thi-bound?

25. ### Ogopogo*Guest

I appreciate it when someone puts that much effort into this kind of work.

One item that I would like to put forth is that, save % is GREATLY skewed by the team in front of the goaltender. A team like Minnesota is structured to allow lower quality shots from farther out than is a team like Ottawa. So, save percentage and all of its deviations are skewed, IMO.

My firm belief is that there is no goaltending statistic that can be relied on to compare goaltenders. The team in front of the goaltender is a major part of how the numbers end up.

As I have said before, put Grant Fuhr on the Canadiens in the 80s and he probably wins 3 Vezinas and has 50 career shutouts.