GPA is my 2nd favorite hitting stat behind OBP. It is a refinement of the OPS formula giving a higher weighted value to OBP% over SLG%.
Gross Production Average or GPA is a baseball statistic created as a refinement of On-Base Plus Slugging (OPS). GPA attempts to solve two frequently cited problems with OPS. First, OPS gives equal weight to its two components, On Base Percentage (OBP) and Slugging Percentage (SLG). In fact, OBP contributes significantly more to scoring runs than SLG does. Sabermetricians have calculated that OBP is about 80% more valuable than SLG.
GPA=
Stats through 3/13/2015:
