



But it is subject to all kinds of bias, and is almost completely useless
for first basemen.  From the raw stats, there is no way to tell which of
a first baseman's putouts were made on throws from other fielders, and
which were made on his own plays; likewise, you can't tell whether a
double play was 6-4-3 or 3-6-3.  Fielding Runs thus gives a first
baseman no credit for putouts or double plays, only for assists and
errors.  

It thus favors first basemen who play deep, reaching a lot of balls but
forcing the pitcher to cover first more frequently.  It also hurts first
baseman who play behind left-handed pitching staffs and thus face few
left-handed batters.


This is better; of course, it still isn't all of a first baseman's
defense.


Defensive Average, which uses larger (and probably better) zones, has
Mattingly tied for second in the league.


While 233 batting runs is good, it is mostly in the past; the runs he
produced in 1986 don't say much about his value in 1993.  
