tl;dr: Bryce Harper’s so-called “bust” seasons weren’t busts at all–they were normal variation. When you plot his monthly OPS on a Process Behavior Chart, the data show consistent performance with a few true signals, not a decline. The problem isn’t Harper’s output; it’s how we misinterpret routine ups and downs without the right statistical context. I’m updating this post with data from the past two seasons, especially since Bryce Harper is considered to be a … Continue reading Is Bryce Harper a Bust–or Is It Just Variation? A Process Behavior Chart Look at Performance