September 10, 2007

Player Save Percentage

I'm a big believer in "shot quality" as many readers have likely noticed. If players have an impact on the quality of shots a goalie sees, then they should affect how many pucks the goalie stops. If a goalie generally stops 90% of shots then a player who makes shots twice as easy to save should have a save percentage of 95%. Of course players have a much smaller impact of save percentage than goalies do.

In order to see if players can affect save percentage I did a season vs. season regression: I check if the players who out performed in 2005-2006 continued to outperform in 2008-2007. If there is a significant relationship between the two seasons then obviously players impact save percentage.

The regression does come out significant, which agrees with the theory that players can affect shot quality.
The regression is reasonably simple:
Difference in team's save percentage in 2006 vs. 2007 = D
Player's Save Percentage in 2006 = Save%
So:
Player's Save Percentage in 2006 = 0.7 + 0.235*Save% + 0.618*D
Basically the above equation is a regression towards the mean: it takes extreme values and brings them closer to the average (0.920).

Note: this data only includes even strength shots.

However, this data is worthless for predicting how a player will do next year due to the large amounts of variability. For example Crosby had a n excellent save percentage this season of 0.930, this system says he'll likely perform at 0.919 given identical goaltending as last season, however he could easily do as poorly as 0.890 with bad luck or as well as 0.950 with good luck. A 2% difference in save percentage on 600 shots works out to about 12 goals over the course of a season. So this large range of possible save percentages for players can have a large impact of a player's plus-minus, often due to just luck.

Results
Any way most people will want to see the results

NILastnameSave%Shots
1TGreen0.98885
2ASemenov0.982109
3SBates0.972216
4PSejna0.96893
5JKrog0.967122
6MHartigan0.96658
7CKobasew0.964274
8SParker0.96151
9BIsbister0.960126
10APeters0.95896
11CThorburn0.958143
12AEdler0.95792
13BMcgrattan0.95690
14APerezhogin0.955313
15JLangfeld0.95567
16RFitzpatrick0.954307
17RPetrovicky0.954109
18RMartinek0.954325
19JOrtmeyer0.954173
20RCallahan0.95263
21MNilson0.951286
22TPreissing0.950443
23SNichol0.950260
24MChouinard0.950139
25JHudler0.949256
26DMccarty0.94978
27CSchubert0.948424
28COrr0.947133
29PHarrold0.94757
30AHutchinson0.947150
31SMccarthy0.947187
32AMair0.946298
33CJanssen0.94693
34JVigier0.946297
35SSalo0.946445
36PBouchard0.946461
37JSlater0.945330
38MHossa0.945293
39JDowd0.945200
40JJokinen0.945361
41EBoulton0.944126
42JCowan0.944233
43SVeilleux0.944374
44KHuselius0.944425
45RRegehr0.943633
46MSillinger0.943509
47GLaraque0.943315
48FKaberle0.943140
49AWozniewski0.94387
50JGreen0.942226
51TWhite0.942467
52CMacarthur0.94286
53BRolston0.942481
54SHartnell0.941358
55CNeil0.941425
56PGaustad0.941237
57CSimon0.940318
58MModano0.940301
59JLeclair0.940117
60BRitchie0.940266
61JTambellini0.94083
62TVanek0.940531
63AFerence0.939577
64HSedin0.939494
65MMalik0.939477
66SBernier0.939310
67ABrooks0.93865
68JFranzen0.938308
69BLebda0.938370
70GZanon0.938418
71RGetzlaf0.938337
72MJohnson0.937510
73JLehtinen0.937366
74RHamrlik0.937636
75JKlemm0.937190
76BGuerin0.937427
77JZeiler0.93779
78BMezei0.937300
79NAlexeev0.936391
80DRoy0.936500
81HZetterberg0.936327
82VFiddler0.936389
83DMarkov0.936420
84CPronger0.936482
85CKelly0.936466
86GExelby0.936419
87DVyborny0.935480
88CPerry0.935325
89TLinden0.935339
90KCarney0.935462
91DLegwand0.935615
92KFoster0.935369
93NLidstrom0.935553
94DHeatley0.935643
95DHamel0.935153
96TSantala0.935107
97PStefan0.935168
98DSedin0.934488
99DBoyd0.93461
100AGreene0.934122
101BMuir0.934137
102AKastsitsyn0.934137
103AAsham0.934350
104BAllen0.934182
105BRafalski0.934743
106OTollefsen0.934393
107GMetropolit0.934332
108DMoore0.934346
109OSaprykin0.934376
110MLombardi0.933480
111JPandolfo0.933615
112VFilppula0.933255
113DPaille0.933150
114MPouliot0.933225
115BWitt0.933703
116MRozsival0.933538
117MAfinogenov0.933388
118ARadulov0.933313
119BHolik0.933506
120MGiordano0.933208
121LEriksson0.933282
122SHnidy0.933460
123ANasreddine0.933252
124DAlfredsson0.932548
125ELindros0.932222
126RFedotenko0.932503
127KTkachuk0.932487
128CChelios0.932383
129BGervais0.932324
130RZednik0.932265
131JSchultz0.932265
132MParrish0.932337
133JFriesen0.932336
134NWelch0.932146
135JModry0.931423
136SMontador0.931350
137PSchaefer0.931480
138MSkoula0.931669
139AVolchenkov0.931566
140KTimonen0.931624
141PKessel0.931434
142AYashin0.931405
143JHoggan0.931159
144PDatsyuk0.931419
145RWarrener0.931433
146BOrpik0.931519
147TPoti0.931634
148BBetts0.931389
149MErat0.930488
150SMellanby0.930330
151HTallinder0.930416
152PMarleau0.930516
153RHollweg0.930314
154GDe vries0.930699
155SCrosby0.930556
156AMarkov0.930641
157JRuutu0.930298
158PThoresen0.929326
159MStuart0.92985
160JStaal0.929354
161JMadden0.929566
162TKostopoulos0.929382
163MRycroft0.929240
164VKozlov0.929564
165THunter0.929437
166MJones0.929338
167SWeber0.929689
168BGionta0.929351
169ARourke0.92970
170DCleary0.928348
171TPlekanec0.928501
172TAmonte0.928417
173MWalker0.928264
174MOhlund0.928624
175MFisher0.928402
176TZajac0.928471
177MStraka0.928429
178MNaslund0.928498
179DFritsche0.928332
180DKasparaitis0.928166
181PKariya0.928650
182MGaborik0.928318
183MZidlicky0.928608
184JPavelski0.928221
185MSvatos0.927303
186NPratt0.927468
187AHilbert0.927399
188MMowers0.927440
189ASteen0.927467
190MSchneider0.927439
191BBurns0.927466
192JWoywitka0.927178
193TPyatt0.927397
194AZyuzin0.927246
195PMara0.927697
196JSim0.927355
197CPhillips0.927641
198JBlake0.927586
199BCoburn0.927327
200PAxelsson0.927422
201RLang0.926435
202RBonk0.926462
203TSelanne0.926461
204SGomez0.926447
205DLangkow0.926501
206JArnott0.926460
207SBrylin0.926527
208RGlobke0.92654
209MJurcina0.926472
210RWhitney0.926619
211JOduya0.926497
212SUpshall0.926188
213MBradley0.925308
214CRivet0.925629
215TDaley0.925495
216CSarich0.925548
217TNumminen0.925668
218LKukkonen0.925454
219JSpezza0.925493
220DKalinin0.925706
221SHill0.925706
222AEriksson0.925479
223SAvery0.925479
224SYelle0.925306
225FBeauchemin0.925585
226BMclean0.925411
227DBackes0.925212
228BMay0.925106
229JFinger0.925106
230CKunitz0.924450
231NSchultz0.924622
232IKovalchuk0.924569
233RSuter0.924567
234YStastny0.92479
235BYoung0.924105
236EBelanger0.924472
237KJohnsson0.924590
238DHale0.924236
239DSydor0.924485
240JSpacek0.924432
241MGreen0.924432
242SStaios0.924471
243JShelley0.924157
244KMclaren0.924510
245MRecchi0.923549
246JHeward0.923483
247WSmith0.923261
248RJohnson0.923313
249CWhite0.923625
250RMalone0.923364
251ATanguay0.923559
252MGoc0.923286
253BJones0.92352
254MMethot0.923117
255DBriere0.923649
256AFoote0.923493
257OVaananen0.923492
258JJacques0.923142
259BGordon0.923413
260RPolak0.922129
261BLukowich0.922605
262MHolmqvist0.922296
263BSeabrook0.922579
264WWalz0.922373
265KRachunek0.922463
266DHordichuk0.922128
267PRissmiller0.922320
268MComrie0.922371
269JLiles0.922370
270PMartin0.922727
271NBaumgartner0.92251
272JIginla0.922561
273CMacdonald0.922102
274KBarch0.92251
275MMichalek0.921433
276ACarter0.921331
277SDonovan0.921496
278WMitchell0.921483
279MOuellet0.921381
280CAdams0.921292
281KBieksa0.921660
282PTenkrat0.921368
283BShanahan0.921406
284MKomisarek0.921685
285BRichardson0.921342
286JStoll0.921266
287DWeight0.921456
288MDandenault0.921456
289SSullivan0.921354
290KHuskins0.921177
291ZParise0.921543
292CConroy0.921467
293DPhaneuf0.921719
294MHavlat0.921340
295CBrown0.921340
296SO'donnell0.921554
297KStewart0.921151
298AZhitnik0.920704
299VNieminen0.920176
300THolmstrom0.920314
301MCarle0.920427
302PForsberg0.920339
303PDemitra0.920477
304MBarnaby0.920138
305ERasmussen0.920276
306AMeszaros0.920701
307DHamhuis0.920688
308VVishnevski0.920500
309SRucchin0.920300
310RCraig0.920324
311DBrashear0.920274
312JChimera0.920498
313JGorges0.920336
314DGirardi0.920199
315SHannan0.920609
316ASutton0.920410
317FMeyer iv0.920410
318SZubov0.919546
319GParros0.91962
320ABurrows0.919285
321JLundqvist0.919161
322CLarose0.919297
323BJackman0.919506
324VKozlov0.919543
325MSatan0.919543
326BRichards0.919617
327BSutherby0.919407
328LSmid0.919629
329SThornton0.919148
330PTurgeon0.91974
331MKoivu0.919443
332SRuzicka0.919209
333JKolnik0.918319
334JCorvo0.918515
335BLaich0.918331
336BLarsen0.918331
337DBoogaard0.91898
338CBarker0.918245
339MNylander0.918502
340RDvorak0.918502
341TLydman0.918514
342LStempniak0.918428
343MGelinas0.918379
344NHagman0.918391
345EBrewer0.918733
346WPrimeau0.918464
347FModin0.918415
348RShannon0.918244
349MHossa0.918561
350ASvitov0.918353
351KDraper0.918426
352JLangenbrunner0.918511
353RDavison0.91873
354MSmith0.918158
355JHecht0.918571
356BRadivojevic0.918425
357JStumpel0.918437
358CEhrhoff0.918461
359AMiettinen0.917315
360SPahlsson0.917436
361CBackman0.917436
362JJagr0.917557
363CGratton0.917448
364SRobidas0.917387
365PKubina0.917387
366JWilliams0.917387
367JRivers0.917181
368JThornton0.917482
369TKaberle0.917554
370PElias0.917445
371SMorrisonn0.917637
372BCampbell0.917661
373PBoucher0.917504
374MHejduk0.917492
375RRobitaille0.917468
376RPark0.917324
377DWideman0.917468
378GPlatt0.917108
379NDempsey0.91772
380JNieuwendyk0.91772
381JDipenta0.917360
382MLehtonen0.91796
383TRoche0.917252
384OJokinen0.917611
385ILaperriere0.916419
386TMoen0.916419
387YPerreault0.916383
388MBergeron0.916490
389BBochenski0.916227
390AAlberts0.916669
391BMccabe0.916657
392KWellwood0.916238
393AVermette0.916464
394ZChara0.916737
395MCooke0.916451
396JHamilton0.916344
397TPock0.916249
398LRichardson0.91683
399GCampbell0.916308
400PO'sullivan0.916225
401NPaetsch0.916367
402RSmyth0.915473
403AMcdonald0.915473
404KBeech0.915307
405MCammalleri0.915519
406GWesley0.915401
407RKlesla0.915613
408RNash0.915471
409RPotulny0.915153
410RHainsey0.915588
411MRibeiro0.915341
412BClymer0.915423
413BSalvador0.915505
414PNummelin0.915387
415SSamsonov0.915387
416DTanabe0.915398
417CColaiacovo0.915316
418JDumont0.914538
419AKarlsson0.914187
420EChristensen0.914292
421JO'neill0.914362
422MCullen0.914478
423RTorres0.914478
424ONolan0.914407
425BWinchester0.914232
426BClark0.914637
427KMaltby0.914359
428NHavelid0.913682
429NHorton0.913520
430SBarnes0.913439
431DArkhipov0.913439
432MVan ryn0.913566
433RSalei0.913658
434VPeltonen0.913404
435TFedoruk0.913288
436JLundmark0.913357
437ROlesz0.913380
438RBlake0.913541
439SGonchar0.913633
440JHejda0.913310
441MZigomanis0.913344
442DMoss0.913172
443FSjostrom0.913401
444PFischer0.913126
445DArmstrong0.913378
446MMalhotra0.912444
447RNiedermayer0.912432
448MStajan0.912477
449AMiller0.912636
450ASemin0.912488
451AWard0.912692
452PStastny0.912476
453RKesler0.912238
454MVlasic0.912578
455JBouwmeester0.912747
456LNagy0.912464
457KKlee0.912645
458BSmolinski0.912430
459EPerrin0.912509
460ALaaksonen0.912147
461JKlepis0.912147
462JTootoo0.912260
463MGrier0.912452
464MNorstrom0.911621
465JPominville0.911564
466DHinote0.911203
467JSakic0.911575
468CClark0.911518
469MEaton0.911259
470CStillman0.911281
471DDrake0.911303
472MTalbot0.911370
473JFahey0.91156
474SChistov0.911224
475YTremblay0.91156
476PDupuis0.911425
477MLapointe0.911369
478BHedican0.910402
479AHall0.910301
480JWisniewski0.910301
481SOtt0.91078
482EJovanovski0.910399
483JSmith0.910676
484JVandermeer0.910299
485GRoberts0.910454
486RJackman0.910155
487AHemsky0.910354
488SNiedermayer0.910575
489BMorrow0.910210
490MPeca0.910221
491LKrajicek0.909464
492NAntropov0.909298
493MBell0.909352
494EStaal0.909593
495AFrolov0.909549
496PEaves0.909417
497MSavard0.909647
498RScuderi0.909515
499SSouray0.909679
500JMcclement0.909416
501TTaylor0.909175
502MRupp0.909175
503FPisani0.908459
504MRoy0.90898
505TRuutu0.908381
506NKronvall0.908413
507LVisnovsky0.908554
508DMcammond0.908357
509APonikarovsky0.907400
510BGuite0.907162
511NTarnasky0.907205
512WRedden0.907550
513RVrbata0.907408
514JBulis0.907397
515CHiggins0.907397
516JMelichar0.907515
517BMorrison0.907460
518DMurray0.906128
519FTyutin0.906458
520PBrisebois0.906213
521BPothier0.906596
522TBertuzzi0.90685
523TLetowski0.906244
524MHandzus0.90653
525DBooth0.906180
526RClowe0.906254
527KSauer0.905327
528SBegin0.905274
529CCampoli0.905274
530AKopitar0.905474
531SHorcoff0.905558
532BSopel0.905431
533MSturm0.905473
534SKoivu0.905515
535KBallard0.905536
536JHalpern0.905399
537JImmonen0.90563
538WWolski0.905451
539BBattaglia0.905409
540TMarchant0.905283
541RBrind'amour0.905524
542MReasoner0.905377
543MRucinsky0.904293
544CArmstrong0.904449
545RBourque0.904261
546JMayers0.904480
547AOvechkin0.904697
548MBlunden0.90452
549AKovalev0.904499
550SDoan0.904478
551MPettinger0.904363
552GBrule0.903321
553GMurray0.903445
554MStreit0.903362
555MSundin0.903434
556MLashoff0.90393
557DTjarnqvist0.903258
558SWeiss0.903412
559WBelak0.903144
560PRanger0.903504
561MMurray0.90372
562JPitkanen0.903719
563IWhite0.903503
564SFedorov0.902441
565BStuart0.902727
566MRyder0.902480
567PCajanek0.902388
568DMaclean0.90251
569ABabchuk0.902367
570JVasicek0.902377
571ALilja0.902295
572BBoyes0.902518
573JNovotny0.902325
574DTucker0.901284
575ECole0.901446
576APicard0.901526
577TGilbert0.90191
578JPerrault0.901101
579JRoenick0.901363
580JNiinimaa0.901252
581EMalkin0.901453
582DKeith0.901664
583KSkrastins0.900572
584HGill0.900530
585MSamuelsson0.900210
586JSmithson0.900240
587BEager0.900269
588MLapierre0.900259
589MRichards0.899358
590DJanik0.899467
591DPenner0.899367
592RWhitney0.899524
593NBoynton0.899395
594PBergeron0.899513
595DBrown0.899483
596DStafford0.898256
597CDrury0.898413
598JWard0.898354
599TFleischmann0.898118
600TArnason0.898412
601DBoyle0.898676
602AKotalik0.898362
603SEminger0.898606
604PPrucha0.898381
605GLatendresse0.897429
606TSalmelainen0.897224
607CKilger0.897437
608DZubrus0.897602
609FBouillon0.897484
610BKane0.89758
611ZMichalek0.897638
612GMurray0.897174
613ADowney0.89758
614TPetersen0.897319
615DLarman0.89758
616MKnuble0.896405
617FKuba0.896588
618PBondra0.896154
619JCarter0.896460
620TGleason0.895411
621AJohnson0.895343
622SThornton0.895295
623BWillsie0.895428
624SWalker0.895485
625DMorris0.895608
626DRichmond0.895133
627BAllen0.894635
628JLeopold0.894123
629NWallin0.894473
630PSykora0.894454
631MTjarnqvist0.894208
632JCheechoo0.894378
633MRyan0.894132
634RAbid0.89466
635ARoy0.894113
636NKapanen0.894386
637SGagne0.894489
638JTimonen0.893122
639SKapanen0.893477
640JYork0.893318
641ZStortini0.89384
642JPohl0.893298
643JCullimore0.892406
644MWeaver0.891229
645ABrunette0.891531
646BThomas0.891128
647JReich0.891128
648DClarkson0.89164
649JGratton0.890146
650RIvanans0.890209
651JWilliams0.890525
652DHatcher0.889714
653MCommodore0.889612
654SO'brien0.889459
655DByfuglien0.88954
656ALadd0.888269
657MGreene0.888529
658BDevereaux0.887186
659JLupul0.886482
660KCalder0.885444
661BBell0.885234
662VLecavalier0.884604
663SReinprecht0.883274
664JKwiatkowski0.883154
665MYork0.883333
666SOzolinsh0.883162
667PSharp0.882485
668MSt. louis0.882637
669VProspal0.881599
670KPushkarev0.88159
671GSanderson0.881302
672DAfanasenkov0.880408
673JErskine0.879248
674LNycholat0.879132
675NZherdev0.879387
676DSeidenberg0.878337
677EMeloche0.87757
678DWestcott0.877146
679JTaffe0.87689
680RUmberger0.876468
681AAucoin0.875361
682OTverdovsky0.875120
683DSyvret0.875120
684DGauthier0.875279
685RJones0.874365
686JMckee0.873173
687PNedved0.873212
688DScatchard0.870230
689NEkman0.869175
690ASuglobov0.86853
691DReid0.86853
692MSt. pierre0.86552
693KDallman0.860235
694MRathje0.854144
695KAdams0.854253
696ELisin0.841113
697BBerard0.84075
698DCarcillo0.82686

4 comments:

David Johnson said...

Is this all shots, or just even strength shots? You should probably just consider even strength shots.

JavaGeek said...

just even strength shots?

I forgot to mention it at first, but it's in there now.

Vic Ferrari said...

Terrific stuff. Do you plan to post shooting percentage numbers for while players were on the ice?

Also, I have a script somewhere that generates these numbers from the shift charts, which aren't as accurate of course, but they do go back a few years. If you post just the 5v5 numbers I'll compare and see how accurate it is.

oilswell said...

Nice job doing a regression test, but what evidence do you have that the players themselves are more significant factors than the profile of opposition quality the players see?