Controlling for the Number of Times a Batter Encountered a Given Peacher

hang chen di learned quite a bit about baseball for someone who finds that life is too short to watch it. What else did she have to control for? So one potential concern is people were treated two tems with different qualities, putin shows and performancert so address this possibility. She also controlled for the difference in moving from the american league to the national league, verses from the national league to the an league. And finally, di controlled for the date of the trade, the point in the season at which it took place....