10/2/2012: Fargo, ND – I have covered the use of the Fielding Independent Pitching (FIP) statistic in evaluating pitching performance and predicting future performance through comparing it with Earned Run Average (ERA) in past articles linked here,  here and here.  I’m not going to go into rehashing the details as you can read full explanations in those earlier articles, but I’ll restate the components that go into creating the final FIP number for pitchers:

FIP = [[(13 * HR + 3 * BB) – 2 * K]/IP]+ 3.2

(Add 3.2 to bring the number to an approximate ERA that assumes average defense supporting the pitcher)

The resulting number is assumed to be a clearer picture of what the pitcher’s expected influence is in regards to run prevention and is easily comparable to ERA.  As stated in the previous articles on FIP, the immediate glaring weakness of this statistic is the influence of park factors on home runs allowed by the pitcher.  West Virginia’s Allegheny Field had the lowest park factor for home runs this season, whereas Canton’s Svab Memorial Stadium had the highest.  Pitchers pitching in these parks had their home runs allowed influenced by the play of the park.  Keep this in consideration when viewing the rankings below.

Once past the drawbacks, my favorite use of FIP is to subtract a pitcher’s ERA from his FIP and look to find the luckiest and unluckiest pitchers, in regards to what FIP is telling us, in the league.  Here, with a little examination, we can make predictions towards where a pitcher might be heading in relation to their ERA potentially bouncing back in either direction next season.  Also, there’s room to speculate on team defense if we start seeing trends such as the majority of starters on a staff having a FIP that is consistently higher or lower than their ERA.

First, we will look at the top 15 pitchers by ERA, with their FIP and FIP-ERA included for comparison.  The list of pitchers only includes those with at least 100 innings pitched and 50% of their appearances coming as the game’s starter.  I did not want to look at pitchers primarily used as relievers, as it is easier to pitch one or two innings in relief than to pitch five or more as a starter, facing the opposing lineup multiple times in a game.  I am planning a separate article to look at relievers in the upcoming week, so for now let’s look at these starters:

The almighty Markus Hancock dominated the league ERA rankings again (he also led both leagues last season with a 2.39 ERA).  This time, he was the only player on this list to lower his ERA below 2.00.  Last season, he was able to limit his HR/9 (home runs allowed per 9 IP) to a miniscule .27.  This season he saw the number of his HRA double from 7 last seasons to 14 but still boasted an impressive .54 HR/9.  We see that his FIP is the lowest on this list and only .12 higher than his ERA, supporting the picture that what we see in dominant ERA performance is in fact the real deal.  Those strikeout and walk totals are pretty amazing, aren’t they?

The top nine pitchers by ERA also boast FIPs below 3.00, with the exception of José Cruz (3.25 FIP).  We can assume this means that, for the most part, these pitchers were not overly lucky in their placement so high in the rankings.

In taking a look at José Cruz, we find the largest discrepancy between ERA and FIP of any top ten pitcher (only Cedric Mosley had a greater discrepancy when considering all of the pitchers on the above list).  A 3.25 FIP is still a very good number and nothing to be ashamed of.  We have a nice comparison by simply looking up one player above Cruz on the list above.  Tetsuo Okazaki’s innings pitched, strikeouts and walks are all fairly close to Cruz’s.  It’s the HRA that separate the two pitchers’ FIP numbers.  Cruz, who pitches for the Crystal Lake Sandgnats, is pitching in a home park that has been completely neutral at allowing HRs when looking at three-year park averages.  This would seem to indicate he is not particularly unlucky in giving up HRs at the rate he has because of park factors.  Cruz’s HR/9 was .93 last season and .87 this season after a couple years of keeping it below .70.  The 31-year-old may be showing some signs of aging in this regard, seeing his batted balls against turning into home runs at a higher rate than in his prime.  Ironically, he has seen his BABIP (Batting Average of Balls in Play) drop the past two years (.276 in 2011 and .249 this year), which has helped him post impressive WHIPs and countered the impact of the HRA.  If he has been able to influence his BABIP through changes in pitching approach or through an above average defense behind him, it may be possible for him to continue to post ERAs lower than his FIP, though it is not likely to be this great of a discrepancy next year.

Now onto Mosley, the right-handed pitcher whose FIP is almost a full run higher than his ERA.  Mosley’s HRA saw an uncharacteristic jump from .53 HR/9 in 2011 to 1.08 HR/9 this season.  He also is pitching his home games in the park that was ranked second in favoring HRA.  Farmer Field, home of the Florida Featherheads, had a HRA park factor of 1.10.  There’s a lot pointing towards bad luck when considering Mosley’s track record in avoiding giving up the long bomb and the potential park effects on HRA.  As it stands, Mosley will have to reduce his HRA going into next season; otherwise, I would expect a regression to occur in his ERA.

Next, we’ll look at the FIP-ERA discrepancy for pitchers with the greatest discrepancy in their favor (i.e. luck has helped them achieve a lower ERA than their FIP would suggest):

Luis Peña is in danger for quite a correction if you follow this list.  He’s definitely benefited from a low BABIP of .253 this season, but he also had a low one last season (.263).  The problem for Peña has been that his K/BB ratio has dipped under 2.0 two out of the three past seasons.  The veteran will also be turning 36 next season, and one has to wonder how long can he keep on fooling hitters into hitting weak grounders once he starts to lose some of those skills to age.

Carlos Cervantes is a weird pitcher.  Here is a guy who pitched 113 innings and only managed to strike out 29 hitters, actually fewer than the number he walked (33).  He does all this and manages an ERA under 4.00.  FIP absolutely does not like him and sees him as below league-average.  He survives on avoiding home runs and limiting walks.  He seems to be playing with fire with that low strikeout rate.

You tend to see one specific stat that pops up as a warning flag for these guys on this list.  Artie Tillman and Sergio Guillén gave up too many home runs.  Barney Sharp is giving up too many walks.  Desmond Barnes is walking too many and not striking out hitters enough, which is double the trouble if he doesn’t turn that around next season.

Lastly, I want to present a group of starting pitchers that were unlucky per their FIP-ERA.  I removed a few pitchers that simply pitched poorly even in regards to FIP (i.e. FIP over 5.00) and had higher ERAs (i.e. 6.50 ERA).  I am not as interested in these types of pitchers, as they will likely pitch better next season if for no other reason than it will be quite difficult to pitch any worse (or a more likely result is that they will be doing their pitching in AAA).

Sergio López pitched much better than his ERA would indicate.  For one, he ate innings, racking up over 200 IP.  Next, he struck out almost exactly a batter per inning while posting a better than 2.0 K/BB.  His HRA is a little high but not all that bad (.97 HR/9).  So where is the bad luck coming from?  You don’t have to go much further than that ugly .358 BABIP.  Without the data available, I would wonder if his left on base percentage (LOB%) may have been unusually low.  This is also considered a “luck” statistic, along with BABIP and HR/FB to a degree.

There are two other pitchers with FIPs below 4.00 on the list above.  Brad Bland and José Martínez both pitched considerably better than their ERA would indicate.  Both will likely see a regression in their favor next season if they continue to pitch similarly.  Bland does have some problem allowing walks but tempers this with fewer home runs given up.