Read this article to learn more about the PH% (Poorly Hit) and VH% (Value Hit) stats. You may see those stats in the main stat spreadsheet and not quite understand what they are or what they mean, this article should help clear up any questions you may have. You may also be interested in reading about the updates to the system.
A general introduction to the methods I use to incorporate running speed. The system remains almost entirely intact, but I have since added a few small corrections here and there to fix small problems. I'm not happy with this system, and I would love to get rid of it, but I haven't found a better solution. Which is a low bar, since I don't feel this solution is very good.
The first public introduction to xStats. Some of the methods described here are obsolete, but the core concepts remain intact. Keep in mind that the window and bucket system has been updated to more resemble a kernel based approach; park factors and handedness factors were added; and exit velocities are modified and corrected for measurement error.