Could there be some survivor bias that explains the late age up-tick in swing percentage on balls in the zone? I wonder particularly whether these guys might be short stops and other sorts of players who stick around based on their defensive skill set and who have always been high-swing, high-contact (but low power) hitters.
Comment by philosofool — October 8, 2012 @ 1:15 pm
I do think this study would benefit from separating players in some way based on hitting ability, perhaps based on power. Sammy Sosa and bonds, who was already a patient hitter, experienced big upticks in walk percentage during their careers. And watching them play, they definitely became more selective, which is why they became more productive. I doubt they are isolated scenarios.
Very interesting though.
Comment by Crumpled Stiltskin — October 8, 2012 @ 1:40 pm
“The biggest change we see relative to age 21 is for O-Contact%, which decreases almost 5% by the time hitters reach 30 years old.”
Don’t you mean 40 years old? Or am I reading the graph wrong?
I’ve done some study on hitter aging. One additional consideration I looked at is years in MLB. I found that most improvements happen from MLB-experience-years 4-6. It takes about 5 years for hitters to become what they will become.