Mariners "elite" starting rotation xERA and SIERA

[Seattle or Bust]

I take it then you aren't a fan of xwOBA either (with regard to evaluating batters).

Which ERA estimator do you like the most?

Yeah because again, I think there is a skill in a hitter placing a ball regardless of velocity (sadly the art is going away).

Luis Arraez is a good example... he's 3rd in BA, 35th in OBP, but 110th in xwOBA.

His Savant page is literally a thesis on why hard-hit metrics do not tell the full story surrounding success of a hitter:



I think I agree that for the most part a pitcher who strikes out a lot of batters and limits hard contact is going to often be among the best pitchers in baseball. So in that sense, estimators are fine. But Jamie Moyer had a hell of a career pitching to contact and letting his defense work for him.

[bpj]

It's not trying to be predictive of the future, it's being predictive of what likely should have happened with a batted ball rather than what actually happened. Pitcher A has a bunch of seeing eye dribblers, broken bar hits and pitcher B has a bunch of line drive outs. As xERA would be higher and Bs lower in terms of what would have been expected. It's taking defense out of the equation. How much of the difference between the ERA of A and B is B having better defense behind them

Sounds like a bunch of nonsense.

[Sibelius Hindemith]

SIERA is regarded as one of the best ERA estimators out there. Here is a table of our starters with their actual ERAs next to their SIERAs.

Code: Select all

Player    ERA   SIERA
Kirby     3.77  3.72
Gilbert   3.69  3.46
Woo       3.44  3.50
Castillo  5.53  3.97
Hancock   2.78  3.35
Miller    1.71  3.24

[Sibelius Hindemith]

Updated table...

Code: Select all

Player    ERA   SIERA

Miller    1.71  3.07
Hancock   2.80  3.29
Gilbert   3.69  3.48
Woo       3.44  3.53
Kirby     3.77  3.75
Castillo  5.53  4.04