Jays of '91: Stat Report

"What is the evidence, and what does it mean?" Bill James
Equivalent Average, R27, Age, On-Base Percentage and Slugging Percentage for every 1991 Blue Jay (and American League leaders).

Link to Jays page. Link to other Stat Reports.

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The 1991 Toronto Blue Jays
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Games Played By Position:

        First Base: John Olerud 135, Ed Sprague 22, Pat Tabler 20,
                    Cory Snyder 4, Rene Gonzales 2

       Second Base: Roberto Alomar 160, Rene Gonzales 11

         Shortstop: Manuel Lee 138, Rene Gonzales 36, Eddie Zosky 18

        Third Base: Kelly Gruber 111, Ed Sprague 35, Rene Gonzales 26,
                    Ray Giannelli 9, Rance Mulliniks 5, Cory Snyder 3

          Outfield: Devon White 156, Joe Carter 151, Candy Maldonado 52,
                    Mark Whiten 42, Mookie Wilson 41, Rob Ducey 24,
                    Cory Snyder 14, Derek Bell 13, Glenallen Hill 13,
                    Kenny Williams 9, Turner Ward 6, Pat Tabler 1

           Catcher: Greg Myers 104, Pat Borders 102, Randy Knorr 3,
                    Ed Sprague 2

  Starting Pitcher: Todd Stottlemyre 34, Jimmy Key 33, David Wells 28,
                    Juan Guzman 23, Tom Candiotti 19, Dave Stieb 9,
                    Denis Boucher 7, Jim Acker 4, Mike Timlin 3,
                    Willie Fraser 1, Pat Hentgen 1

    Relief Pitcher: Duane Ward 81, Mike Timlin 60, Jim Acker 50,
                    Tom Henke 49, Bob MacDonald 45, Dave Weathers 15,
                    Willie Fraser 12, David Wells 12, Ken Dayley 8,
                    Vince Horsman 4, Frank Wills 4, Al Leiter 3,
                    Pat Hentgen 2, Mickey Weston 2

 Designated Hitter: Rance Mulliniks 81, Pat Tabler 57, Mookie Wilson 34,
                    Glenallen Hill 16, Dave Parker 11, Joe Carter 11,
                    Candy Maldonado 9, Rob Ducey 2, Kelly Gruber 2, 
                    Kenny Williams 2, Ed Sprague 2, John Olerud 1

           Manager: Cito Gaston 66-54, Gene Tenace 19-14, Cito Gaston 6-3

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1991 in Context
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The revamped Jays won the organization's 3rd division title, but the Jays again
faltered in the playoffs, losing 4 of 5 to the Twins in the ALCS, who went on
to edge the Braves in the battle of former last-place teams in the Series.
SkyDome hosted the All-Star Game and drew 4 million fans for the first time:

 Runs Scored Per 9 IP   Runs Allowed Per 9 IP        Winning Percentage
( 1)     Detroit 5.07 | ( 1)     TORONTO 3.83 | ( 1)   Minnesota  95-67  .586
( 2)       Texas 5.04 | ( 2)   Minnesota 4.05 | ( 2)     TORONTO  91-71  .562
( 3)   Milwaukee 4.91 | ( 3)  California 4.05 | ( 3)   White Sox  87-75  .537
( 4)   Minnesota 4.82 | ( 4)     Seattle 4.14 | ( 4)       Texas  85-77  .525
( 5)     Oakland 4.74 | ( 5)   White Sox 4.15 | ( 5)      Boston  84-78  .519
( 6)   White Sox 4.62 | ( 6) Kansas City 4.43 | ( 5)     Detroit  84-78  .519
( 7)      Boston 4.57 | ( 7)      Boston 4.45 | ( 5)     Oakland  84-78  .519
( 8) Kansas City 4.46 | ( 8)   Milwaukee 4.57 | ( 8)     Seattle  83-79  .512
( 9)     Seattle 4.31 | ( 9)   Cleveland 4.74 | ( 8)   Milwaukee  83-79  .512
(10)   Baltimore 4.24 | (10)     Oakland 4.84 | (10) Kansas City  82-80  .506
(11)     TORONTO 4.21 | (11)   NYYankees 4.84 | (11)  California  81-81  .500
(12)   NYYankees 4.20 | (12)   Baltimore 4.91 | (12)   NYYankees  71-91  .438
(13)  California 4.08 | (13)     Detroit 4.93 | (13)   Baltimore  67-95  .414
(14)   Cleveland 3.60 | (14)       Texas 4.95 | (14)   Cleveland  57-105 .352
             Avg 4.49                Avg 4.49                   1134-1134     

Correcting the above for park factor, the '91 Jays had the 2nd-worst hitting in
the league, after being 2nd-best the previous year.  The Jays didn't find a DH
after trading Fred McGriff (and moving Olerud to 1B).  Gruber, Borders and Lee 
hit significantly worse than the year before.  George Bell's departure was not
a big factor because he was not very productive the previous year:

 Team Equivalent Average:
    1    2    3    4    5    6    7    8    9   10   11   12   13   14
   TEX  MIL  OAK  DET  CHW  MIN  KAN  BAL  BOS  SEA  NYY  CAL  TOR  CLE
  .275 .272 .272 .272 .265 .263 .259 .258 .257 .255 .253 .250 .250 .237

Correcting runs allowed for park factor, the '91 Jays had the best pitching &
defense in the league, more than making up for the shortcomings of the offense.
Devo in centre may have been an important contributor:

 Opponents' Equivalent Average:
    1    2    3    4    5    6    7    8    9   10   11   12   13   14
   TOR  MIN  CAL  SEA  BOS  CHW  KAN  MIL  CLE  NYY  DET  TEX  BAL  OAK
  .240 .245 .249 .251 .254 .254 .258 .265 .265 .267 .269 .273 .273 .274

SkyDome was rated a hitters' park in 1991 with a park factor of 1.035: 

 Park Factors ((PF-1)*100, hitters' parks first):
    1    2    3    4    4    6    6    6    9   10   11   11   13   14
   BOS  MIN  TOR  CLE  DET  KAN  NYY  SEA  CAL  TEX  MIL  CHW  BAL  OAK
   5.0  4.5  3.5  1.0  1.0   .5   .5   .5   .0 -2.0 -2.5 -2.5 -3.5 -6.0
 (derived from park factors in Total Baseball, 5th ed., which are based
  on data from 1990-1992 except when the park changed; see Glossary)

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'91 Hitters
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1991 marked the beginning of the Jays' 2nd great era.  Before the season, the
Jays traded Fred McGriff and Tony Fernandez to the Padres for Roberto Alomar
and Joe Carter, who became the team's best two hitters.  Also before the 
season, the Jays traded OF Junior Felix, IF Luis Sojo and C Ken Rivers to the
Angels for Devon White, RHP Willie Fraser and RHP Marcus Moore.  John Olerud
moved from DH to first-base, and Manuel Lee moved from 2B to SS:

                Age        EqA   BA  OBP  SLG  R27   EqR   R RBI HR  SB CS   PA
  Roberto Alomar 23 S 2B  .286 .295 .353 .436  5.65  102  88  69  9  53 11  694
      Joe Carter 31 R RF  .286 .273 .325 .503  5.63  105  89 108 33  20  9  687
     Devon White 28 S CF  .282 .282 .339 .455  5.44  101 110  60 17  33 10  697
     John Olerud 22 L 1B  .280 .256 .352 .438  5.37   72  64  68 17   0  2  522
    Kelly Gruber 29 R 3B  .263 .252 .302 .443  4.55   59  58  65 20  12  7  460
 Rance Mulliniks 35 L DH  .262 .250 .366 .333  4.55   32  27  24  2   0  0  284
      Greg Myers 25 L  C  .257 .262 .309 .411  4.31   39  25  36  8   0  0  330
     Pat Borders 28 R  C  .225 .244 .272 .354  3.10   27  22  36  5   0  0  302
      Manuel Lee 26 S SS  .206 .234 .273 .288  2.49   34  41  29  0   7  2  469

On Aug 9/91, the Jays picked up Candy Maldonado from the Brewers for RHP Rob
Wishnevski and 2B William Suero, solidifying George Bell's former position.
Ed Sprague showed some potential in his rookie season:

                Age        EqA   BA  OBP  SLG  R27   EqR   R RBI HR  SB CS   PA
 Candy Maldonado 30 R LF  .288 .277 .360 .446  5.73   29  26  28  7   3  0  200
      Ed Sprague 23 R 3B  .266 .275 .352 .394  4.70   22  17  20  4   0  3  179
  Glenallen Hill 26 R DH  .258 .253 .302 .434  4.38   13  14  11  3   2  2  106
      Pat Tabler 33 R DH  .226 .216 .322 .270  3.13   18  20  21  1   0  0  214
   Mookie Wilson 35 S OF  .225 .241 .265 .349  3.10   23  26  28  2  11  3  249
     Mark Whiten 24 R OF  .219 .221 .275 .329  2.89   13  12  19  2   0  1  160
   Rene Gonzales 30 R SS  .191 .195 .269 .246  2.06    8  16   6  1   0  0  130

Dave Parker was acquired too late to help the Jays at DH in the playoffs.
Derek Bell made his major league debut: 

                Age        EqA   BA  OBP  SLG  R27   EqR   R RBI HR  SB CS   PA
     Dave Parker 40 L DH  .294 .333 .400 .444  6.06    6   2   3  0   0  1   40
     Randy Knorr 22 R  C  .288 .000 .500 .000  5.73    0   0   0  0   0  0    2
  Kenny Williams 27 R OF  .252 .207 .303 .379  4.12    4   5   3  1   1  0   33
     Turner Ward 26 S OF  .247 .308 .357 .308  3.91    1   1   2  0   0  0   14
       Rob Ducey 26 L OF  .245 .235 .297 .368  3.84    8   8   4  1   2  0   74
   Ray Giannelli 25 L 3B  .211 .167 .310 .208  2.65    2   2   0  0   1  0   29
      Derek Bell 22 R OF  .180 .143 .294 .143  1.78    2   5   1  0   3  2   34
     Eddie Zosky 23 R SS  .126 .148 .148 .259   .73    1   2   2  0   0  0   27
     Cory Snyder 28 R OF  .112 .143 .192 .184   .55    1   4   6  0   0  0   52

Triples:
 Roberto Alomar 11, Devon White 10, Mookie Wilson 4, Joe Carter 3,
 Manuel Lee 3, Mark Whiten 3, Rob Ducey 2, Kelly Gruber 2, Glenallen Hill 2,
 Rance Mulliniks 1, John Olerud 1, Cory Snyder 1, Pat Tabler 1,
 Eddie Zosky 1

Doubles (leaders):
 Joe Carter 42, Roberto Alomar 41, Devon White 40, John Olerud 30,
 Greg Myers 22, Kelly Gruber 18, Manuel Lee 18, Pat Borders 17

Times On Base (Hits + Walks) (leaders):
 Roberto Alomar 245, Devon White 236, Joe Carter 223, John Olerud 184,
 Kelly Gruber 139, Manuel Lee 128, Rance Mulliniks 104, Greg Myers 102

Outs (AB-H+CS) (leaders):
 Joe Carter 473, Devon White 471, Roberto Alomar 460, Manuel Lee 343,
 John Olerud 340, Kelly Gruber 328, Greg Myers 228, Pat Borders 220

Strikeout-to-Walk Ratio:
 Manuel Lee 4.5, Mookie Wilson 4.4, Pat Borders 4.1, Glenallen Hill 3.4,
 Mark Whiten 3.2, Devon White 2.5, Candy Maldonado 2.3, Joe Carter 2.3,
 Ed Sprague 2.3, Kelly Gruber 2.3, Greg Myers 2.1, Rene Gonzales 1.8,
 Roberto Alomar 1.5, John Olerud 1.2, Rance Mulliniks 1.0, Pat Tabler .7

Games Played (leaders):
 Joe Carter 162, Roberto Alomar 161, Devon White 156, John Olerud 139,
 Manuel Lee 138, Kelly Gruber 113, Greg Myers 107, Pat Borders 105

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'91 Starting Pitchers
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Juan Guzman was called up June 4/91 to replace the injured Dave Stieb and had
an awesome rookie year, including a victory in the Metrodome in the playoffs
(note: playoff stats aren't included below).  On June 27/91, the Jays traded OF
Glenallen Hill, OF Mark Whiten and LHP Denis Boucher to the Indians for 
knuckleballer Tom Candiotti and OF Turner Ward.  Key, Stottlemyre and Wells
filled out a fantastic starting rotation (all with EqAs much better than the
average of .260):

                Age    W  L  ERA   RA*   R27    IP   EqA  BA   OBP  SLG HR  K/9
     Juan Guzman 24 R 10  3  2.99  3.28  2.84 138.7 .220 .197 .291 .280  6  8.0
   Tom Candiotti 33 R  6  7  2.98  3.27  3.39 129.7 .228 .236 .301 .330  6  5.6
       Jimmy Key 30 L 16 12  3.05  3.35  3.58 209.3 .231 .254 .292 .358 12  5.4
Todd Stottlemyre 26 R 15  8  3.78  4.15  3.76 219.0 .244 .235 .299 .364 21  4.8
     David Wells 28 L 15 10  3.72  4.08  4.05 198.3 .247 .251 .297 .402 24  4.8

Pat Hentgen showed signs of his future form in his first opportunities in the
majors.  Dave Stieb pitched great before back and shoulder injuries ended his
effective pitching years (or so we thought for a long time):

                Age    W  L  ERA   RA*   R27    IP   EqA  BA   OBP  SLG HR  K/9
     Pat Hentgen 22 R  0  0  2.45  2.69  3.49   7.3 .221 .208 .296 .375  1  3.7
      Dave Stieb 33 R  4  3  3.17  3.48  3.74  59.7 .235 .243 .316 .355  4  4.4
   Denis Boucher 23 L  0  3  4.58  5.03  5.80  35.3 .277 .279 .353 .466  6  4.1

Games Started:
 Todd Stottlemyre 34, Jimmy Key 33, David Wells 28, Juan Guzman 23,
 Tom Candiotti 19, Dave Stieb 9, Denis Boucher 7, Jim Acker 4,
 Mike Timlin 3, Willie Fraser 1, Pat Hentgen 1

Complete Games:
 Tom Candiotti 3, Jimmy Key 2, David Wells 2, Juan Guzman 1, Dave Stieb 1,
 Todd Stottlemyre 1

Innings Pitched Per Game (IP/G):
 Tom Candiotti 6.8, Dave Stieb 6.6, Todd Stottlemyre 6.4, Jimmy Key 6.3,
 Juan Guzman 6.0, Denis Boucher 5.0, David Wells 5.0, Pat Hentgen 2.4

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'91 Relief Pitchers
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The Terminator had his 7th consecutive year as an awesome closer, and Duane
Ward had his 4th consecutive year as a workhorse setup man.  Mike Timlin had
his best season in his rookie year:

                Age    W  L  ERA   RA*   R27    IP   EqA  BA   OBP  SLG HR  K/9
       Tom Henke 33 R  0  2  2.32  2.55  2.08  50.3 .197 .184 .232 .292  4  9.5
      Duane Ward 27 R  7  6  2.77  3.04  2.44 107.3 .211 .207 .270 .281  3 11.1
     Mike Timlin 25 R 11  6  3.16  3.47  3.73 108.3 .235 .233 .318 .333  6  7.1
   Bob MacDonald 26 L  3  3  2.85  3.13  4.50  53.7 .240 .252 .335 .384  5  4.0
       Jim Acker 32 R  3  5  5.20  5.71  4.63  88.3 .271 .238 .314 .433 16  4.5

Would that Leiter kid ever put it together?

                Age    W  L  ERA   RA*   R27    IP   EqA  BA   OBP  SLG HR  K/9
   Mickey Weston 30 R  0  0   .00   .00  1.41   2.0 .122 .143 .250 .179  0  4.5
   Vince Horsman 24 L  0  0   .00   .00  2.58   4.0 .156 .167 .333 .209  0  4.5
   Dave Weathers 21 R  1  0  4.91  5.39  6.67  14.7 .289 .263 .432 .378  1  8.0
   Willie Fraser 27 R  0  2  6.15  6.75  6.30  26.3 .298 .303 .367 .480  4  4.1
      Ken Dayley 32 L  0  0  6.23  6.84  9.22   4.3 .324 .368 .500 .461  0  6.2
     Frank Wills 32 R  0  1 16.62 18.24 14.23   4.3 .429 .421 .542 .816  2  4.2
       Al Leiter 25 L  0  0 27.00 29.63 15.92   1.7 .491 .429 .667 .536  0  5.4

Relief Appearances:
 Duane Ward 81, Mike Timlin 60, Jim Acker 50, Tom Henke 49, Bob MacDonald 45,
 Dave Weathers 15, Willie Fraser 12, David Wells 12, Ken Dayley 8,
 Vince Horsman 4, Frank Wills 4, Al Leiter 3, Pat Hentgen 2,
 Mickey Weston 2

Saves:
 Tom Henke 32, Duane Ward 23, Mike Timlin 3, Jim Acker 1, David Wells 1

Innings Pitched Per Game (IP/G):
 Willie Fraser 2.0, Mike Timlin 1.7, Jim Acker 1.6, Duane Ward 1.3,
 Bob MacDonald 1.2, Frank Wills 1.1, Tom Henke 1.0, Vince Horsman 1.0,
 Mickey Weston 1.0, Dave Weathers 1.0, Al Leiter .6, Ken Dayley .5

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1991 American League Leaders
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Shortstop Cal Ripken won his 2nd MVP award, and was a reasonable choice.  Cecil
Fielder (.297 EqA, 113 EqR) finished 2nd in the voting and was miffed he didn't
win, but he didn't even deserve to be in the top ten.  In the voting, Thomas
was 3rd, Canseco 4th, Carter 5th, Alomar 6th, Clemens 10th, Molitor 11th, Jack
Morris 13th and Devon White 16th:

Top 14 Hitters by EqA (minimum 330 plate appearances):
                         EqA   BA  OBP  SLG  R27   EqR   R RBI HR  SB CS   PA
    Frank Thomas CHW DH .353 .318 .453 .553  9.03  145 104 109 32   1  2  697
 Danny Tartabull KAN OF .335 .316 .397 .593  8.13  110  78 100 31   6  3  549
      Cal Ripken BAL SS .327 .323 .374 .566  7.37  137  99 114 34   6  1  703
     Ken Griffey SEA OF .325 .327 .404 .527  7.56  115  76 100 22  18  6  619
 Rafael Palmeiro TEX 1B .322 .322 .388 .532  7.19  129 115  88 26   4  3  699
    Jose Canseco OAK OF .322 .266 .354 .556  6.87  127 115 122 44  26  6  650
    Julio Franco TEX 2B .320 .341 .407 .474  7.09  117 108  78 15  36  9  654
    Paul Molitor MIL DH .317 .325 .395 .489  6.86  131 133  75 17  19  8  742
   Harold Baines OAK DH .314 .295 .386 .473  6.45   97  76  90 20   0  1  560
      Wade Boggs BOS 3B .313 .332 .425 .460  7.17  102  93  51  8   1  2  635
    Lou Whitaker DET 2B .312 .279 .395 .489  6.85   94  94  78 23   4  2  560
Rickey Henderson OAK OF .312 .268 .394 .423  6.35  100 105  57 18  58 18  568
Mickey Tettleton DET  C .309 .263 .387 .491  6.67  100  85  89 31   3  3  602
     Chili Davis MIN DH .307 .277 .386 .507  6.79  104  84  93 29   5  6  629

44-year-old Nolan Ryan got his 7th no-hitter on May 1/91, striking out 16 Jays.
Roger Clemens won his 3rd Cy Young Award, and deservedly so.  Tom Candiotti
deserved 2nd-place based on his combined Cleveland-Toronto performance (238 IP,
~.219 EqA), but got no votes.  Scott Erickson was 2nd, Jim Abbott 3rd, Jack 
Morris 4th, and Duane Ward tied for 9th in the voting.  The below does not
include Jack Morris' 10-inning shutout in Game 7 of the Series, just before he
became a free agent:

Top 14 Starting Pitchers by EqA (minimum 123.7 innings pitched):
                      W  L  ERA   RA*   R27     IP   EqA  BA   OBP  SLG HR  K/9
   Roger Clemens BOS 18 10  2.62  2.87  2.77  271.3 .212 .221 .269 .318 15  8.0
      Nolan Ryan TEX 12  6  2.91  3.19  2.30  173.0 .216 .172 .262 .271 12 10.6
     Juan Guzman TOR 10  3  2.99  3.28  2.84  138.7 .220 .197 .291 .280  6  8.0
 Bret Saberhagen KAN 13  8  3.07  3.37  2.96  196.3 .226 .228 .273 .331 12  6.2
   Tom Candiotti TOR  6  7  2.98  3.27  3.39  129.7 .228 .236 .301 .330  6  5.6
    Kevin Tapani MIN 16  9  2.99  3.28  3.45  244.0 .228 .245 .277 .376 23  5.0
       Jimmy Key TOR 16 12  3.05  3.35  3.58  209.3 .231 .254 .292 .358 12  5.4
      Jim Abbott CAL 18 11  2.89  3.17  3.53  243.0 .231 .244 .300 .348 14  5.9
     Bill Wegman MIL 15  7  2.84  3.12  3.42  193.3 .231 .242 .282 .363 16  4.1
   Mark Langston CAL 19  8  3.00  3.29  3.58  246.3 .234 .215 .292 .362 30  6.7
  Scott Erickson MIN 20  8  3.18  3.49  3.80  204.0 .235 .248 .312 .357 13  4.8
   Jack McDowell CHW 17 10  3.41  3.74  3.33  253.7 .239 .228 .291 .341 19  6.8
     Jack Morris MIN 18 12  3.43  3.76  3.88  246.7 .240 .245 .314 .360 18  5.9
     Chris Bosio MIL 14 10  3.25  3.57  3.60  204.7 .240 .244 .297 .359 15  5.1

The Terminator made this list again:

Top 7 Relievers by EqA (minimum 50 innings or 10 saves):
                      W  L  ERA   RA*   R27     IP   EqA  BA   OBP  SLG HR  K/9
      Doug Henry MIL  2  1  1.00  1.10  1.11   36.0 .150 .133 .224 .190  1  7.0
    Bryan Harvey CAL  2  4  1.60  1.76  1.93   78.7 .182 .178 .224 .280  6 11.6
  Todd Frohwirth BAL  7  3  1.87  2.05  1.97   96.3 .191 .190 .254 .254  2  7.2
   Mark Eichhorn CAL  3  3  1.98  2.17  2.19   81.7 .195 .219 .252 .293  2  5.4
       Jeff Gray BOS  2  3  2.34  2.57  2.11   61.7 .197 .181 .218 .316  7  6.0
       Tom Henke TOR  0  2  2.32  2.55  2.08   50.3 .197 .184 .232 .292  4  9.5
   Rick Aguilera MIN  4  5  2.35  2.58  2.40   69.0 .202 .183 .274 .264  3  8.0

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Theory Stuff, 1991
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The Jays' Pythagorean Record was down 4 wins from 1990, but this year's team
overachieved by 3 instead of underachieving by 6 to have a better actual
record.  (Note that I've changed the 2nd column from past reports to show extra
wins instead of missed wins (i.e. the numbers are negated compared to before)):

      Pythagorean WPct     Extra Wins
 ( 1) MIN  94-68  .579 | ( 1) OAK   5
 ( 2) CHW  89-73  .549 | ( 2) TOR   3
 ( 3) TOR  88-74  .543 | ( 3) TEX   3
 ( 4) MIL  86-76  .533 | ( 4) MIN   1
 ( 5) SEA  84-78  .519 | ( 5) BOS   1
 ( 6) DET  83-79  .513 | ( 6) DET   1
 ( 7) BOS  83-79  .512 | ( 7) KAN   0
 ( 8) TEX  82-80  .508 | ( 8) NYY   0
 ( 9) KAN  82-80  .503 | ( 9) CAL   0
 (10) CAL  81-81  .503 | (10) SEA  -1
 (11) OAK  79-83  .490 | (11) CHW  -2
 (12) NYY  71-91  .435 | (12) BAL  -3
 (13) BAL  70-92  .432 | (13) MIL  -3
 (14) CLE  61-101 .376 | (14) CLE  -4

Note: PythagWPct = RF^1.83 / ( RF^1.83 + RA^1.83 )
      where RF=Runs For and RA=Runs Against

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Glossary
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General:
 Equivalent Average (EqA): corrects runs per 9 innings for park factor and 
  rescales so that .260 is average and .300 represents excellence every year:
   EqA = ( (( R9 / PF ) / AvgR9) * (.260 ^ (1 / 0.4)) ) ^ 0.4
    where R9 = Runs per 9 innings (defined differently in each section below)
          PF = Park Factor (see explanation in Team section below)
          AvgR9 = Average Runs per 9 innings in Year (see each section below)
          ^ 0.4 makes distribution much like batting average's
   Note: Equivalent Average was invented by Clay Davenport as a 'hitter' stat.
         My application of EqA to 'teams' and 'pitchers' may differ from what 
         he would do, and my formulas and park factors for 'hitters' differ,
         but my resulting hitter EqAs are very similar in practice.
 Estimated Runs Produced: ERP = 0.16*(3H+2D+4T+6HR+2BB+SB-0.605*(AB-H+CS)),
  invented by Paul Johnson, more accurate than Bill James' runs created,
  background info available at http://www.stephent.com/jays/erp.html
 ERPAdj: ratio of league's Runs to ERP, always close to 1.0, 1.006 in 1991
 Age: as of July 1, 1991

Team Stats Glossary:
 Runs Scored Per 9 IP: runs scored per 9 innings pitched by the team, not
  against the team (the latter would be preferable but is harder to find).
  For example, in 1991, the Jays scored 684 runs, allowed 622 runs, and
  pitched 1462.7 innings, from which the listed numbers were calculated.
 Team Equivalent Average: in EqA formula above, R9 is team's runs scored per 
  9 IP, and AvgR9 is league average runs per 9 IP (4.49 in 1991)
 Opponents' Equivalent Average: R9 is team's runs allowed per 9 IP
 Park Factor (PF): divisor which corrects run totals for park effect;
  Total Baseball, 5th ed. lists two park factors for each team, one for hitters 
  and one for pitchers, to correct for the advantage of not facing your own 
  team's pitching or vice versa, a minor detail.  I took the average of the two
  park factors for each team and normalized them so that their product was 1.0.
  Example, if TB5's park factors were 105 and 106, I would average them to 
  105.5, which after normalization might be 1.054.  To not repeat the 1.0 and 
  0.9 prefixes excessively, the listed numbers are (PF-1)*100.  For example, 
  the park factor of 1.054 would be listed as 5.4.  To get the park factor (PF)
  from the listed number, divide it by 100 and add 1.  TB5's park factors are 
  based on data from 1990-1992 except when the park changed.

Hitting Stats Glossary:
 Group1: hitters with 9 most plate appearances (more if tie for 9th in PA)
 Group2: other hitters with at least 100 PA
 Group3: remaining hitters
 L/R/S:  bats Left, Right, or Switch
 EqA: Equivalent Average, in formula above, R9 = R27 * ERPAdj (R27 defined below,
       ERPAdj defined above), AvgR9 = 4.49 / 1.04 (estimate of Major League 
       average from 1991 American League average, 1.04 accounts for DH rule)
  BA: Batting Average, (H/AB), inaccurate measure of batting ability (ignores
      power, walks, stealing, park factor, league average), use EqA instead
 OBP: On-Base Percentage, estimated as (H+BB)/(AB+BB)
 SLG: Slugging Average, (H+D+2T+3HR)/AB
 R27: estimate of how many runs a lineup of that player would score in a game,
      i.e. ERP per 27 outs, in 1991, 25.7*ERP/(AB-H+CS), average roughly 4.49
 EqR: Equivalent Runs, park-adjusted Estimated Runs Produced scaled so that
      100 represents excellence every year, EqR=(ERPAdj*ERP/PF)*(4.50/AvgR9),
      AvgR9 same as in hitter EqA, results similar to Clay Davenport's
   R: Runs Scored
 RBI: Runs Batted In, inaccurate measure of run production, use EqR instead
   D: Doubles,  T: Triples,  HR: Home Runs,  AB: At Bats,  BB: Walks
  SB: Stolen Bases,  CS: Caught Stealing
  PA: Plate Appearances (estimated as AB+BB)

Pitching Stats Glossary:
 Starting Pitcher = at least one-third of appearances were starts
 Group1: starting pitchers with 5 most starts (more if tie for 5th in starts)
 Group2: remaining starters
 Group3: relief pitchers with 5 most relief appearances
 Group4: remaining relievers
   W: Wins,  L: Losses,  L/R: Left-hander or Right-hander
 ERA: Earned Run Average (9*ER/IP), ER = Earned Runs allowed
  RA: Run Average (9*R/IP), R = total Runs allowed
 RA*: RA estimated from ERA because pitcher runs is an astonishingly hard stat
      to find for non-recent years; in 1991, estimated as 1.10*ERA
 R27: ERP per 27 outs (9*ERP/IP, ERP estimated as below)
  IP: Innings Pitched
 EqA: Equivalent Average against pitcher, based on ERA, RA* and R27:
       in EqA formula, let R9 = (1.10*ERA)/6 + (RA*)/3 + (1.006*R27)/2
       and AvgR9 = American League average runs per 9 IP (4.49 in 1991),
       not as accurate a stat as hitter EqA, but better than just ERA
  BA: Batting Average against pitcher
 OBP: On-Base Percentage against pitcher (estimated as (H+BB)/(AB+BB))
 SLG: Slugging Average against pitcher (uses below estimates of D and T)
  HR: Home Runs allowed,  H: Hits allowed,  BB: walks 
 K/9: Strikeouts per 9 innings (9*K/IP)
 ERP: Estimated Runs Produced against pitcher, estimated as follows:
       AB: At Bats, determined from H/BA, rounded to nearest integer
       D: Doubles, estimated as .20*(H-HR) (based on 1991 AL average)
       T: Triples, estimated as .12*D in 1991
       SB: Stolen Bases, estimated as .067*(H+BB-D-T-HR) in 1991
       CS: Caught Stealing, estimated as .52*SB in 1991
       ERP = 0.16*(3H+2D+4T+6HR+2BB+SB-0.605(AB-H+CS))

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Sources
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Most raw data from Sean Lahman's Baseball Archive, http://www.baseball1.com
Ages, left vs right vs switch, games by position, from The Sports Encyclopedia:
 Baseball 17th ed., 1997, David S. Neft and Richard M. Cohen.
Park factors are based on the ones in Total Baseball, Fifth Edition, 1997,
 edited by John Thorn, Pete Palmer, Michael Gershman and David Pietrusza.
 Also, MVP & Cy Young results, and RF, CF & LF positions are from TB5.
Equivalent Average and Equivalent Runs are in the same spirit as described by
 Clay Davenport in Baseball Prospectus 1997 Edition, Gary Huckabay, Clay
 Davenport, Rany Jazayerli, Chris Kahrl, Joseph S. Sheehan, 
 http://www.baseballprospectus.com/
Estimated Runs Produced is described by Paul Johnson in the The Bill James
 Baseball Abstract 1985.
Jays trades are listed in the Toronto Blue Jays Official Guide 1998.
I cannot guarantee that no errors were made in processing or presenting this 
information.

--
Stephen Tomlinson             http://www.stephent.com/jays/
mailto:stephent@ottawa.com                  Ottawa, Ontario
"What is the evidence, and what does it mean?" (Bill James)

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