Harvey is benefiting from a .190 BAbip this year vs. .268 last year. He’s faced 206 batters this year and seen a 61 bip%. So 206*.61*.078 and that’s 10 outs he’s gotten on bip that he wouldn’t have had with last year’s rate. If you subtract 3.1 innings from his total for this year you end up with a K/9 of 10.5.
This is illustrative of one of the weaknesses of K/9 in that it is BAbbip dependent whereas K% is not.
Re Pitcher Velocity: This should stop the standard-issue comments about why most pitchers are willing to use higher risk mechanics to throw harder, as opposed to playing it safe with durability and lower velocity.
Comment by CircleChange11 — May 15, 2013 @ 1:18 pm
im not sure that’s a completely accurate calculation, though I guess I could be wrong. you’re assuming that the only 2 outcomes of those extra ABs would be a hit or strikeout if im not mistaken. what about sac flies?
I’m not sure what you mean by extra ABs. A SF is treated the same as any fly out by BAbip. The Mets are recording outs far more frequently this year than they did last year when a batter puts the ball in play against Harvey. History also tells us that they are recording these outs at a rate that is not sustainable. Because Carson was comparing K/9 from last year to this year I substituted last year’s BAbip for this year’s in order to demonstrate that it had a significant effect on K/9 (he had suggested BB% was also important) and calculated that he had recorded 10 extra outs this year based on this lowered BAbip.
K/9 is simply an expression of what percentage of outs a pitcher records via K’s so it rises and falls with BAbip. If Harvey continues to K the same percentage of batters but more of the batted balls end up being hits his K/9 should rise and approach last year’s rate.