THE BOOK--Playing The Percentages In Baseball

Thursday, August 17, 2006

Is It Easier To Standout in a High Run Environment?

No!

Proof follows:

Let’s use an example. A guy has a wOBA of .200 (i.e, OBP of .200 and SLG of .240). His ERA will be 1.42. A league wOBA of .280 has an ERA of 2.83. In this case, his ERA+ is 199.

Now, how would this guy have done in a .340 OBP league? A .200 in a .280, using the Odds Ratio method, gives us a wOBA of .250. With me so far? A .200 OBP in a .280 league is equivalent to a .250 OBP in a .340 league. That’s the translation.

Now, a .250 wOBA has an ERA of 2.23. A .340 wOBA has an ERA of 4.39. 439/223 = 197

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Odds Ratio Method is:

.200/.800 = O(P1) = p1
.280/.720 = O(L1) = l1
.340/.660 = O(L2) = l2

p / l1 * l2 = p2

In this case, p2 = .331, which translates to an OBP of .331/1.331 = .250