Table of Contents
Here’s the table of contents for today’s edition of Offseason Notes.
1. Graph: Vertical Fastball Movement Vs. Ground-Ball Percentage
2. Projecting: ZiPS for Minnesota
3. Crowdsourcing Broadcasters: Chicago (AL) Television
Graph: Vertical Fastball Movement Vs. Ground-Ball Percentage
Yesterday (Tuesday), site founder David Appelman added Pitch Fx leaderboards to the site. I’m not lying when I say I wanna make, like, a thousand graphs of that data and then take each one of those graphs out individually to a romantic dinner or Will Smith concert.
As mystic philosopher Lao Tzu once said, though, “A journey of a thousand graphs starts with one, uh, graph.” So we’re starting with this one graph right here.
For this one, I made a sweet custom report including the vertical movement (or, z-movement) for two-seamers (FT) and sinkers (SI) — along with the overall ground-ball percentages — for every starter from 2011 (with more than 10 innings). I was curious as to how well vertical movement on those pitches correlates with ground-ball percentages.
In fact, the correlation was much higher than I anticipated. There’s probably some confirmation bias here — that is, pitchers with betters sinkers or two-seamers probably throw those pitches more often — but, speaking anecdotally, there seemed to be a pretty reasonable spread in usage.
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