From: steph@cs.uiuc.edu (Dale Stephenson)
Newsgroups: rec.sport.baseball
Subject: Re: AL Rookie of Year Award?
Date: 30 Sep 92 22:36:50 GMT
Article-I.D.: pegasus.steph.717892610
Organization: University of Illinois, Dept. of Comp. Sci., Urbana, IL

In <1992Sep30.024740.13320@panix.com> spira@panix.com (Greg Spira) writes:

>In article <steph.717806198@pegasus.cs.uiuc.edu> steph@cs.uiuc.edu (Dale Stephenson) writes:
>>In <1992Sep29.043819.9110@panix.com> spira@panix.com (Greg "Sarcasm Is A Way Of Life" Spira) writes:
>>

[snip]
>>
>Okay, but forget offensive value.  Neither of us is interested in that
>right now.  What we're interested in is whether Jeff Blauser's defense
>is more valuable than Devon White's because of the extra difficulty of
>the shortstop position.  Now, I think we both agree that Devon White
>is a much, much, much better centerfielder than Blauser is a shortstop.
>Yes, any other shortstop the Braves would put out there would be more
>valuable defensively.  But I don't think that means Blauser has negative
>defensive value, because you can't compare him just to other shortstops.
>You have to measure his defense in terms of all fielders.

Why can't we compare him to other shortstops?  If we use range numbers
(not perfect at all, but the best I have), Blauser has a hand in 4.17
outs per game, while White is in 3.12.  Blauser is involved in more chances,
but that doesn't keep him from hurting the team.  For instance, to take
the most important defensive position, lets look at pitchers.  Suppose
Mark Davis and his 7.02 ERA is on the mound.  Davis has a role in every
out recorded -- but his net defensive value is still negative.

Pitchers are a rather extreme case, but I think we really need to separate
the importance of the position from the value of the player.   Suppose we
have a team of replacement level players (ignoring pitchers and catchers,
for the time being).  Suppose we can call up one player who will make 10%
more plays than the existing player.  Clearly, the shortstop would have
the most defensive value.  Suppose we can call up one player who will make
one more play than the existing player.  Now it doesn't matter to the defense
who we call up.  Shortstop is still a more important defensive position, but
the called-up shorstop would have the same defensive value (-1 HA) as the
called-up firstbasemen (-1 HA).

Because Blauser is playing short, his defensive non-value is magnified, not
lessened.

[snip]

>To move to an easier example, would you agree that the worst shortstop
>is worth more than the best first baseman? Or a DH?

Well, not since I consider a negative defensive ability possible.  A DH
has zero defensive value, and therefore is better than all defensive
players below replacement level.  (Where that is, I'm not sure.)  Lonnie
Smith, for example, has more defensive value to the team as a DH than as
a LF.

>>Blauser has less defensive value to the Braves than does Otis Nixon (especially
>>if Deion isn't available).  However he's more valuable offensively than
>>Otis.
>>
>What I'm saying, obviously, is that the ability to play shortstop for a
>major league team has a value in and of itself.  Only after you establish
>that value do you add on more value based on exactly how good at that
>position he is.

I am assuming that below-average (but not the worst) defenders are always
available to replace the defender.  If this is not the case (and it is probably
less likely at shortstop than any other position), then playing the position
has some value to the team.

>>>Interestingly, White was sent to the minors after posting numbers that
>>>would probably be acceptable for almost any shortstop but were not
>>>acceptable for the best centerfielder.
>>
>>If we're going to normalize offensive numbers by position, why not normalize
>>defensive numbers?

>Well, we should normalize defensive numbers by position.  That's precisely
>what I'm arguing for.  A bad effort at shortstop should be normalized to
>make it worth more than a good effort in centerfield.

I think a bad effort at shortstop is probably more damaging than a bad effort
in centerfield.

--
Dale J. Stephenson |*| (steph@cs.uiuc.edu) |*| Baseball fanatic

  "It is considered good to look wise, especially when not 
   overburdened with information" -- J. Golden Kimball
Newsgroups: rec.sport.baseball