Here is a simplified version of my calculation-- I call this simplified zub's era (sZERA). In the more complex version, I use K/9 and customize an estimate of gidp/9, sb/9, cs/9, sh/9 and sf/9. Again, the estimate of ERA based on expected h/9, hr/9, bb/9 is pretty accurate. The estimation of h/9 hr/9, bb/9 probably only work with low oavg, low bb/9 pitchers.
h/9 = h/9# * 1.1574
dp/g = 0.6900
cs/9 = 0.3757
sb/9 = 0.9850
bb/9 = bb/9# * 1.3084
hr/9 = hr/9# * 1.2827
sf/9 = 0.0422
sh/9 = 0.0922
tb/hbip = 1.21
ibb/9 = 0.255
A = (h/9 + bb/9 +hbp/9 -cs/9 -gidp/9)
B = [(h/9 - hr/9) * tb/hbip] + (4 * hr/9 +0.26) * (bb/9 - ibb/9 + hbp/9) + [0.52 (sh/9 + sf/9 +sb/9)]
C = 27 - cs/9 - gidp/9
sZERA = A*B / C
10/26/2011 11:54 PM (edited)