Formulas

Batting Formulas
BA H/AB
OBP (H+BB+HBP)/(AB+BB+HBP+SF)
SLG (H+2B+2*3B+3*HR)/AB
OPS (H+BB+HBP)/(AB+BB+HBP+SF) + (H+2B+2*3B+3*HR)/AB
RC ((H+BB)*(H+2B+2*3B+3*HR))/(AB+BB)
BABIP (H-HR)/(AB-K-HR+SF)
ISO SlgPct - OBPct
K% K/PA
BB% BB/PA



Run Differential Predicting Team Performance:
http://www.baseballprospectus.com/article.php?articleid=23497

Pitching Formulas
K/9 K*9/IP
BB/9 BB*9/IP
K% K/BF
BB% BB/BF
LOB% (H+BB+HBP-R)/(H+BB+HBP-(1.3*HR))
BABIP (H-HR)/(AB-K-HR+SF)
FIP ((13*HR)+3*(BB+HBP)-(2*K)/IP)+FIP constant
FIP Constant 3.68
ERA (ER/IP)*9