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How can a fielding independent ERA be higher than the normal ERA? FIP ERA assumes that all ground balls and pop outs are fielded correctly, right? So a pitcher can have fielders that are so good that they give up runs?
FIP ERA assumes that all ground balls and pop outs are fielded correctly, right?
No. FIP completely ignores all batted balls hit into play for the purposes of its calculation. The idea is to strip out as many luck-based elements as possible and measure a pitcher only on the things that are demonstrably under his control.
How can a fielding independent ERA be higher than the normal ERA?
80-90 percent of the variance between a pitcher's ERA and his FIP can be explained by the two things I harped on extensively this morning -- BABIP, and LOB%. Pitchers with poor marks in these categories may have decent, or good, or even great FIPs, but will give up more hits than otherwise expected, will allow more baserunners to score than otherwise expected, and thus will have higher ERAs.
The general idea is that this variance will settle down over time and a pitcher's ERA will become more congruent with his FIP as time goes by, but, obviously, this doesn't always happen in a single season (e.g. former Ranger Chris Young posting a .240 BABIP in something like 180-plus innings back in '06).
Joey, I think Pryor is confused more about how the calculation is made. Maybe he is assuming that that FIP ERA is calculated exactly the same as ERA, counting only runs that are scored by way of BBs/HBP and HRs. If that were so, obviously FIP would be lower than ERA. I think this may help..
Pryor, the fact is that FIP isn't even calculated by runs that are scored. Instead it assigns a numerical value to each variable that is directly controlled by the pitcher: Homeruns, Strikeouts, and Walks/HBP. Those are entered into an equation which subtracts the strikeout-product total from the walk/HBP-product total. From there, you divide it by the total number of innings pitched. The quotient is then added to a constant, 3.20. So even if a pitcher has given up just 1 HR or BB, his FIP will still be higher than 3.20, unless he has a high enough strikeout total to cancel out the other.
The value that is assigned to strikeouts is slightly lower than that which is assigned to walks and it is greatly lower than that which is assigned to HRs. So no matter what a pitcher's ERA is, the likelihood that his FIP ERA would be lower than 3.20 is highly improbable. I hope that helps a bit.
Ah okay, thank you both for the explanation.
3.20 works for a rough estimate of the FIP-ERA constant in the FIP formula. If you want to get really specific and calculate FIP totals for past seasons you can use this list (1871-2009). (The 2010 FIP-ERA constant was approximately 3.16.)
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