reading your excellent work on the Marlins has convinced me to start seriously studying sabermetric concepts.

Anyway a quick question on the concept of Defense Independent Pitching.

The pitcher is actually himself an often not insignificant part of the defense. Somehow it seems the pitcher should get some credit or blame for his own part in the outcome. I was wondering if anyone had come up with a way to factor this in.

Thanks

John

I’d just like to add on to your answer to the other Nick’s question. While FIP-ERA over a half or season may be great in determining how lucky that pitcher gotten, it is relatively useless towards projecting his future performance. For that, you also need to weight his previous seasons and regress to the mean as well.

In Jackson’s case, it doesn’t make much of a difference because he pretty much sucked in his previous season as well; but just going to by first half FIP may prove to be misleading in most cases.

I think you got it mostly right. FIP is definitely going to tell you more about how good a pitcher has pitched, so if you see a high differential between it and ERA, something is definitely afoot. I think his low BABIP was a big trigger as well, perhaps more so than the FIP.

In general, when I evaluate a pitcher, I use FIP to see his production, but I’d check out things like K%, BB%, HR/FB%, and batted balls to see how he’s getting to that FIP. It looks like his HR’s are now where they usually are, and along with some regression from his K’s and BB’s, it’s bumped his FIP and vaulted his ERA.

All in all, you were right to suspect Jackson, Nick. Something was definitely up, and if you’re trying to get the most value for a trade in fantasy, the best idea would be to sell on these “low ERA/BABIP” pitchers whose peripherals (FIP and in particular xFIP) are not nearly as good. Well played, sir.

At the ASB, Edwin Jackson’s ERA was around 2.50 but his FIP was in the high three’s, not to mention he had a relatively low BABIP. I took this information and suggested to my fantasy baseball readers to sell Jackson while they still could, as I believed luck had a great amount of impact on his early success.

Jackson was pounded in the second half to the tune of a 5.07 ERA, raising his season ERA to 3.62, and his season FIP to 4.28. I’m not trying to say, “Hey, I told you so!”, but rather, I’m asking if you think my reasoning to sell Jackson’s fast start was legit?