GPA

From SoSH

Gross Production Average -- Created by Aaron Gleeman, who terms it a variation of OPS, but more accurate and easier to interpret. The formula, which is usually adjusted for park factor:

GPA = [(OBP*1.8) + SLG] / 4

The interpretive scale is similar to BA: .200 is lousy, .265 is around average and .300 is indicative of a good hitter.