The Last, Greatest Post About Austin Jackson & BABIP: Part 4 – Variance

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First of all, here are their career numbers:  bear in mind that due to talent and longevity all of these guys are at least in the running for future admission to the Hall of Fame (where thus far only Carew presently resides):

For reference, so far in 2011 the league as a whole is averaging a BB% of .0845, a K% of .1823, an ISO of .138 a batting average of .252, a BABIP of .297 and OBP of .320 and a slugging percentage of .390. Bear in mind that in spite of the drop in scoring following the end of the juiced era, the 1960s and 1970s (and to a lesser extent 1980s) saw less offense than today.

Now take a look at the players’ standard deviations and standard errors:

Which stats seem the least reliable?

If we compare standard errors for BABIP and Isolated Power, walk rates and strikeout rates – all of which are supposedly much more consistent and predictable attributes than BABIP – it is BABIP that looks like the one to bet on. If we start from the knowledge, after a long career, that a player actually does have (or does not have) BABIP skills we don’t see guys that rely on high BABIP numbers to be productive being any flakier or less consistent than guys that rely on a batting eye or biceps – if anying they may be more consistent and reliable. There is nothing wrong, inherently, with trying to build a team around balls in play skills. Nor is there anything wrong, inherently, with putting a guy in the leadoff slot who needs that high BABIP to set the table. The problem is in recognizing, without the benefit of hindsight, whether those skills exist at all.