zone ratings and batted ball velocity

[dominik]

I understand the zone approach to sabermetric fielding stats. every player gets a zone he has to cover and then you look how many balls into his zone are converted to outs.

But there is one problem I see. range is also dependent on ball velocity. if the ball is softer the range is bigger since you have more time to run to the side. a player might easily get to a soft grounder that is 15 feet to his side while he might only be able to cover 9 feet on a really hard grounder.

do those modern zone ratings account for that?

[leewileyfan]

dominik: From what I have read, some of the current metrics are purportedly based upon "spotters" at ball games, mostly volunteers [I believe] who score and define the nature of batted balls. I have heard that Dewan has employed some camera work in the "spotting" exercise as well.

I have also heard that some sophisticated metrics have encountered problems with inconsistencies in how some "spotters" report batted balls: vagueries between liners, humpback liners, long flies, blasts - whatever.

My personal problem with these efforts is that they are available for varying numbers of seasons, many ten-fifteen years or less. Others going back to 1950 or so have gaps and conflicting data inputs.

I try to capture the historic relevancies with the most basic input data, the actual "work" going into quantifying those basic elements.