From: josh@cbnewsh.cb.att.com (joshua.h.rosenbluth)
Subject: RC/MLV Study
Organization: AT&T
Distribution: na
Date: Sun, 4 Oct 1992 13:53:08 GMT

Here are some notes on a study in progress comparing Marginal Lineup Value (MLV)
to Runs Created per Out (RC/Out) for evaluating offensive individual
contribution:

   *  I took each of the 92 AL players with at least 400 ABs from
      1991.

   *  I computed RC/Out using the Simple Version of RC.

   *  I computed RC Value as Outs*(RC/Out - RC/Out[avg.player])

   *  I computed MLV by assuming that each player got 1/9 of the
      Plate Appearances on an otherwise average team, and scaling
      this result based on actual Plate Appearances (Thank you Dave
      Tate for providing me with the formulae.)

The results to date are:

   *  RC/Out overestimates value.  A good first-order approximation
      is take .79*RC Value to get MLV.

   *  RC/Out's overestimation decreases as a player's SLG-to-OBP ratio
      increases.  That is, if you have two guys with the same RC/Out,
      one of which is a slugger and the other is an on-base guy, the RC
      prediction, based on surrounding a player with 8 clones, does a better
      job for the slugger (Why?  What does this mean?).

   *  The Second order adjustment for the above effect produces:
      MLV = .79*RC Value + 12*SLG/OBP - 15

   *  All of the predicted 92 MLVs (data attached) were within 2 runs of
      the actual MLV except for Griffey, Taratabull and Thomas.  These
      players all have above average SLG-to-OBP ratios and very high (>.38)
      OBP.  That is, they are great hitters.  Also, the predicted MLVs are
      still about 1 to 2 runs too high for players with OBPs > .38 and
      below average SLG-to-OBP ratios.

Comments and next steps:

   *  I didn't believe Dave's comments about MLV and RC/Out at first, but
      I'm pretty much convinced now.

   *  If you don't want to compute MLV directly, you can use the above
      formula starting with RC Value.  But watch out for sluggers with
      high OBPs.

   *  I have to try the formula out on other leagues in other years,
      might as well do the 1992 NL after the final McPaper numbers are
      published.

   *  Then, I'd like to try the more realistic MLV calculation which starts
      with the player's team, takes him out, and then adds back an average
      player.  And then do the same but with position specific replacement
      level substitutes.  And then (someday) add in SBs and CSs.

   *  Finally, doesn't this all mean that the top pitchers are worth more
      compared to the top hitters than we previously thought.  RC/Out has its
      largest errors for the greatest hitters.  Take a look back at the 1987
      Bill James Abstract and read his evaluation of the 1996 Mattingly/Clemens
      and 1978 Rice/Guidry MVP debates.  Is James aware of his mistake?

Josh Rosenbluth (attmail!jrosenbluth)

The data (contact me for the raw data and formulae):

R = RC Value, M = MLV, PM = Predicted MlV (.79*RC Value+12*SLG/OBP-15)

               R     M    PM
Alomar        20    16    15
Baerga         7     5     4
Baines        29    22    23
Bell          15    15    14
Belle         22    23    22
Bichette     -11    -7    -7
Boggs         43    30    32
Brett          2     1     1
Brunansky     -8    -6    -6
Buhner        13    13    13
Burks          0     2     1
Canseco       39    34    35
Carter        23    24    22
Clark         21    15    16
Cuyler        -9    -9   -10
A.Davis      -16   -14   -14
C.Davis       37    28    30
Deer         -10    -9    -8
Deveraux       3     5     4
Espinoza     -16   -13   -13
Fermin       -16   -15   -16
Fielder       29    26    26
Fisk          -6    -2    -3
Franco        46    33    35
Fryman         5     7     6
Gaetti       -14    -9   -10
Gagne         -3    -1    -2
Gallego       -3    -4    -4
Gantner       -5    -5    -6
Gibson         1     0     0
Gladden      -11    -9   -10
Gonzalez      13    14    13
Greenwell     13    11    10
Griffey       52    39    42
Gruber         1     4     4
Guillen      -15   -12   -13
Hall          10    11    10
Harper        12    12    11
D.Henderson   19    17    16
R.Henderson   18    12    12
Hrberk        22    17    17
Jacoby       -22   -19   -19
James        -21   -18   -17
Johnson      -13   -11   -12
Joyner        30    25    25
Kelly          9     9     8
Knoblauch     -2    -4    -4
Lee          -25   -22   -22
Maas          -4    -4    -4
Mack          31    26    27
Martinez      32    23    24
Mattingly      2     1     0
McGwire       -6    -7    -6
McRae        -14    -9   -10
Milligan      11     7     7
Molitor       50    38    39
Nokes          7    10     9
OBrien        -5    -3    -3
Olerud        11     8     9
Orsulak       -6    -5    -6
Palmeiro      55    44    45
Parker       -14   -11   -11
Parrish      -12    -8    -7
Pasqua        15    12    12
Pena         -20   -17   -17
Phillips      21    16    16
Polonia        6     4     3
Puckett       26    22    21
Quintana      15    10    10
Raines        -3    -6    -6
Randolph      18    11    10
Reed           4     2     2
Reynolds     -11   -12   -12
Ripken        61    50    51
Rivera        -3    -3    -3
Sax           14    11    10
Schofield    -24   -23   -24
Sierra        40    33    33
Spiers         4     3     2
Steinbach     -4    -2    -3
Surhoff       -2    -2    -3
Tartabull     56    44    47
Tettleton     31    23    24
Thomas        73    52    58
Vaughn         8     8     8
Ventura       23    17    17
Vizquel      -19   -18   -19
Whitaker      31    23    25
White         18    16    16
Whiten        -7    -5    -5
Winfield      15    15    14
Yount         -2    -3    -3
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