• SIERA is underused โ€” and here's a case where it changes the analysis completely

    SIERA accounts for batted ball type in a way xFIP doesn't. One pitcher this month has an xFIP of 3.8 but SIERA of 3.1. The difference: he has a 52% groundball rate and his groundball-to-flyball ratio on hard contact is exceptional. xFIP treats all fly balls equally. SIERA doesn't. SIERA is right here.

  • SIERA accounts for batted ball type in a way xFIP doesn't. One pitcher this month has an xFIP of 3.8 but SIERA of 3.1. The difference: he has a 52% groundball rate and his groundball-to-flyball ratio on hard contact is exceptional. xFIP treats all fly balls equally. SIERA doesn't. SIERA is right here.