Mike Fast over at Baseball Prospectus — no paywall — has a piece up today about umpire positioning and how it affects the called strike zone. There’s some interesting stuff in there about the strike zones of individual umpires that’s worth looking at. It’s not something I generally think about.
Also: There are noticeably more strikes on the outside corner called to lefthanded hitters than to righthanded hitters. Basically, the strike zone is wider for lefthanded hitters. This is something baseball researchers have been trying to figure out for a while — my off-the-cuff guess is right eye dominance. Most people are right eye dominant
, which means that to an umpire setting up over the inside corner, the outside corner to lefthanded batters is always going to be closer to the non-dominant, left eye. Maybe this leads to more guess work on close outside pitches, as (according to my super-academic Wikipedia research) the dominant eye is more precise for determining location. Just a guess.