A week after ESPN’s Buster Olney decided that Melky Cabrera’s excellent-so-far 2014 season justifies people assuming he’s back on PEDs, ESPN’s Dan Szymborski dives into the numbers and shows that such a decision is not based on any evidence at all:
Despite the rhetoric surrounding PEDs, players caught for steroid/testosterone use do not show a pattern of overperforming their projections in the years leading up to the drug suspension or a pattern of underperforming their projections in the years after a drug suspension.
All of this is based on Szymborski’s ZiPS projection system, which shows that Cabrera is doing about what you’d expect him to do this year. And that, as a group, guys busted for PEDs don’t really deviate too much from their expected performance one way or another before, during or after they are caught for PEDs.
Obviously there are a lot of caveats in play here. Small sample sizes, imperfect data about when guys start and stop taking PEDs and, of course, the flaws any projection system, even one as generally reliable as ZiPS, brings to the table.
But if you’re making a case for something — and Olney and others who are questioning the legitimacy of Melky’s performance this season are clearly making a case for something — it’s incumbent upon you to present some evidence. Szymborski’s analysis doesn’t necessarily prove anything about the efficacy or lack thereof of PEDs. But it has far more evidence on its side than anything people are hurling at Cabrera lately.
