Q.  Would the mainframe consider Sweeney's exploits a case of "small sample size"?

A.  Stop me if you've heard the punch line, but a "statistical sample" is a fraction of a data universe that fairly represents the E-N-T-I-R-E universe.

If you flip a coin 20 times, that's a "sample," because the first 20 trials are completely representative of the next 2,000.  But if you let Matt Tuiasosopo bat 20 times, what does that sample?  He's not going to be the same hitter one month later.

If we're going to try to sound as if we've scientifically "solved" baseball, we might want to start by avoiding this layman's misuse of the phrase "sample size" every other paragraph.  "Sample size" rarely applies to baseball player performance.

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Q.  But is his performance misleading?

A.  Sure.  His OPS+ is 160 so far this year, and the hope is that he could clock in at around 120, maybe 130 in a dream lucky year.

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Q.  What, based on 60 AB's you hope he can suddenly hit?

A.  Sweeney has hit .300/.370/.525 since the All-Star Break last year. 

The John Benson Offseason Rule is that, whoever a hitter was during the second half last year, is who he is going into the next season.  That guy hit a good 300/370/500 last year, in Safeco.  Now he's doing it again.  What are you talking, 60 AB's?   Sweeney has done nothing but rake for 11 consecutive months* now.

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Mike Sweeney, in his prime, was a certified All-Star -- who missed time due to a bad back.  If Josh Wilson hit six homers, that would be a different conversation.  Mike Sweeney is gifted.

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Q.  How does he look, after you adjust for luck?

A.  His HR/F rate is twice what it would normally be, so give him credit for 3 homers instead of 6.  If you turn 3 homers into two outs and a double, he's still slugging well over .500.  Ken Griffey Jr., um, isn't.

His line-drive rate is very low so far, but his BABIP is only .280 compared to his lifetime .301.

The reason his LD rate is low is because his flyball rate is wayyyyyy up.  He's going down there and yanking pitches way over the fence.

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REMEMBER!  Just because Sweeney can't hit 6 homers in 70 AB's, a hundred months in a row, doesn't mean that these 6 homers weren't legit.  Probably pitchers will be more careful with him now.

Don't reason too confidently from the general to the specific application.  These six homers, Sweeney meant to hit homers, deserved to hit homers, and did hit homers.

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Exec Sum:  Sweeney won't sustain a 20% HR/F rate and won't OPS+ 160.  But normalize the luck and he's still an RBI man, still slugging .500 in Safeco.

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Part 2