2012 Fantasy Baseball: Using ERA-FIP Differential for Buy/Sell Purposes
One number doesn’t tell the whole story – and neither does two or three, or twelve or thirteen, even– but if one did, it certainly wouldn’t be Earned Run Average (ERA). Such a fact is a shame, as ERA finds a home in almost all fantasy leagues, yet has some fatal, inarguable flaws. For example, does a defense factor into run prevention? Well, of course. Then why is a defense’s performance weighed so heavily in a metric used to evaluate pitchers? A poor defense can cost a pitcher countless runs, and not just those of the unearned variety.
I won’t be a voice that argues that Fielding Independent Pitching (FIP) is perfect, because it’s not. What it does do, though, is simply measure the factors that we know a pitcher has some or all control over: strikeouts, walks, hit by pitches, and home runs. It takes those raw numbers, punches them out in a simple formula, and produces a number that looks wildly similar to an ERA. The stat doesn’t necessarily predict future performance, but it helps tell us, more accurately, how well a pitcher performed. Not how well their defense was, or how many balls fell on the outfield grass or snuck past the small-range shortstop; just their tangible skills as run-preventers.
And the magic part, unless, of course, this isn’t magic to you at all: subtract the ERA from the FIP, and you have a difference that tells you just how lucky or lucky a certain pitcher’s been relative to the rest of the league. Have a league-mate who lives and dies by the Earned Run Averaged? Here are some potential targets and send-offs as the month of August approaches.
Best Differentials
Tim Lincecum (5.93 ERA, 3.72 FIP, 2.21 ERA-FIP)
’Twas certain that we’d see this season’s biggest enigma on the list, and who can honestly say their surprised to see The Freak with the largest ERA to FIP difference in the league? The former Cy Young winner is in the midst of his worst season in the league by pretty much any and every metric, and while some may chalk this up to bad luck (.330 batting average on balls in play, a low strand rate, a still-elite strikeout rate), things Lincecum can control have played a part in this as well.
The concern here goes beyond just his flailing fastball velocity; his changeup, once upon a time among the best in the game, is suddenly very much ineffective. The difference between his fastball velocity and changeup velocity for his career has been close to nine MPH, but this year the difference has been a mere seven MPH. And for his career, line drives have resulted 2.94% of the time when Lincecum has thrown a changeup. This year Lincecum has allowed a line drive 3.98% of the time when throwing a changeup.
Could that account for the rapid downfall of one of the league’s premier arms? Perhaps. After all, five percent of last year’s ground balls have magically transformed into line drives. He may see his ERA slip closer to 5.00 by season’s end, but something’s awry with Timmy’s arm. Get well soon.
Verdict: Best to stay away.
Jake Arrieta (6.13 ERA, 4.01 FIP, 2.12 ERA-FIP)
Arrieta, oddly enough, is Timmy without the velocity troubles. Au contraire, actually; he’s seen a rise in fastball, slider, curveball, and changeup velocity since last year, and though his once-impressive slider has waned in value, bad luck seems to be Young Jake’s nemesis first and foremost. His home-run rate of 1.15 per nine hardly spells confidence for the Orioles’ arm, but it matches the rate he put up over the previous 200+ innings. This go-round, his strand rate and balls in play have been on the wrong side of lucky, so expect a turnaround that’ll make him deeper-mixed worthy (especially on the road, where his FIP is 3.00). Don’t let it be lost on you, though, that he’s always a blow-up risk.
Verdict: To some, a worthy second half rebound.
Josh Johnson (4.35 ERA, 3.12 FIP, 1.23 ERA-FIP)
One thing’s clear after an ace’s June and a fool’s July, and that’s that Johnson’s been quite the frustration. Behold his monthly ERAs: 5.34 in April, 4.41 in May, 1.87 in June and 7.56 in July. His FIP, meanwhile, has been more stable, never jumping over 4.00 and hovering below 3.00 in two separate months. The burly lefty should expect some line-drive regression as his 25.3% rate against is high for any pitcher, especially someone with two plus-value pitches in his fastball and curveball. He has a spacious, friendly monstrosity of a home park (have you seen that “art” that is unleashed during home-run celebrations?), and a track record of success. Chalk this up to a long post-surgery hangover, and put him high on the list of second-half pitchers to target.
Verdict: Buy, buy, buy.
Adam Wainwright (4.42 ERA, 3.26 FIP, 1.16 ERA-FIP)
Wainwright’s practically the same pitcher he was pre-Tommy John, albeit one with a less biting curve and slower fastball. Still, his peripherals are all in line with his previous dominant self: the only eye-catching difference is how often the balls are crawling out of the park. He’s generating a ton of ground balls to a poor-fielding Cardinals team, for one, and has allowed four homers labeled “Just Enough” or “Lucky” by ESPN Home Run Tracker. And now you see the problem with ERA.
Verdict: Like Josh Johnson, but with a better offense.
Worst Differentials
Jeremy Hellickson (3.55 ERA, 5.32 FIP, -1.78 ERA-FIP)
Not a favorite of the stats community, Hellickson’s strikeout to walk ratio of 1.58 is in the bottom ten of qualified starters (among the likes of Ricky Romero, he of a 5.22 ERA, and Ubaldo Jiminez, he of a 5.24 ERA). So how can a pitcher who strikes out few and walks plenty find his ERA on the right side of 4.00? Some proper good luck, and Hellboy has had it: his .253 BABIP is tied for 10th among qualified starters. It is borderline impressive that he’s managed a 3.55 ERA despite his seventeen home runs allowed, but that’s merely a function of their nature: 13 have been solo shots. And to put some icing on the very concerning cake, only two Hellickson-served homers have been of the “Just Enough” variety. Yeah, as if you needed more reasons to sell him.
Verdict: Waiting to blow up.
Ryan Vogelsong (2.31 ERA, 3.73 FIP, -1.42 ERA-FIP)
Think of this as a mutual breakup: you two have had something of a glorious run, yet it’s clear the best days are over. You end your relationship with a mutual respect for and an appreciation of one another, and perhaps even stay in contact and good graces. The obvious key to the breakup is that Vogelsong’s key drawing point, his 2.31 ERA, is aided by all types of luck: batted ball average, line drive rate, strand rate, low home run rate. So, as well-liked as he’s been in the fantasy community this year (for proving the haters of his glorious 2011 breakout campaign wrong), his owners can’t seriously expect the same standard of success as they found in the first half.
Luckily Vogelsong owners have a pitcher with good roto ratios and respectable peripheral numbers; in other words, his owners have a very valuable trade chip to a wide variety of roto players. He’ll be on the wrong side of luck in the second half (expect his ERA to crawl closer to last year’s 2.71 mark by year’s end), but if you get the combination of 1st half Vogelsong and 2nd half Johnson – and you’ll have to be plenty adept to pull off that trade – for a late-round draft pick, you’ll have the tip of my hat.
Verdict: Bid him a sad farewell, and thank him for all he’s done.
Ryan Dempster (1.86 ERA, 3.13 FIP, -1.27 ERA-FIP)
Over the last four years, Dempster has flashed remarkable consistency with his peripheral stats. The range of his FIP marks from 2008-2011 was a mere half run. His xFIP mark – which factors in regressed, league-average home run rates – ranged a mere .07 runs over the four year period. His strikeout to walk rate in the time span was somewhere between 2.33 and 2.65 at every year’s end. The only thing that hopped around was his ERA, which crawled from 2.96 up to 3.65, followed by a 3.85 mark and a 4.80 dud last year. It was any analyst’s dream: Dempster simply struggled with some ill luck, and was a clear turnaround candidate.
No one expected this, though: a scoreless innings streak greater than R.A. Dickey’s, an ERA under 2.00 in late-July, and even pretty WHIP numbers (his career mark, for reference, is 1.43). And while it doesn’t take an expert to tell you Dempster’s ERA won’t hang out near 2.00 for much longer, he may find yet another stroke of good luck in an impending trade. If Dempster ends up in L.A. pitching for the Dodgers, he’ll find himself a very pitchers-friendly home park and in a division that includes the Padres of PETCO Park and the Giants of AT&T Park. Take a page out of Epstein’s book and sell with caution and poise…
Verdict: …but definitely sell.
Follow Nick Fleder, who runs the Fantasy Department at The Hardball Times, on Twitter at @fishfle. Email him at nick DOT fleder AT gmail DOT com.
I won’t be a voice that argues that Fielding Independent Pitching (FIP) is perfect, because it’s not. What it does do, though, is simply measure the factors that we know a pitcher has some or all control over: strikeouts, walks, hit by pitches, and home runs. It takes those raw numbers, punches them out in a simple formula, and produces a number that looks wildly similar to an ERA. The stat doesn’t necessarily predict future performance, but it helps tell us, more accurately, how well a pitcher performed. Not how well their defense was, or how many balls fell on the outfield grass or snuck past the small-range shortstop; just their tangible skills as run-preventers.
And the magic part, unless, of course, this isn’t magic to you at all: subtract the ERA from the FIP, and you have a difference that tells you just how lucky or lucky a certain pitcher’s been relative to the rest of the league. Have a league-mate who lives and dies by the Earned Run Averaged? Here are some potential targets and send-offs as the month of August approaches.
Best Differentials
Tim Lincecum (5.93 ERA, 3.72 FIP, 2.21 ERA-FIP)
’Twas certain that we’d see this season’s biggest enigma on the list, and who can honestly say their surprised to see The Freak with the largest ERA to FIP difference in the league? The former Cy Young winner is in the midst of his worst season in the league by pretty much any and every metric, and while some may chalk this up to bad luck (.330 batting average on balls in play, a low strand rate, a still-elite strikeout rate), things Lincecum can control have played a part in this as well.
The concern here goes beyond just his flailing fastball velocity; his changeup, once upon a time among the best in the game, is suddenly very much ineffective. The difference between his fastball velocity and changeup velocity for his career has been close to nine MPH, but this year the difference has been a mere seven MPH. And for his career, line drives have resulted 2.94% of the time when Lincecum has thrown a changeup. This year Lincecum has allowed a line drive 3.98% of the time when throwing a changeup.
Could that account for the rapid downfall of one of the league’s premier arms? Perhaps. After all, five percent of last year’s ground balls have magically transformed into line drives. He may see his ERA slip closer to 5.00 by season’s end, but something’s awry with Timmy’s arm. Get well soon.
Verdict: Best to stay away.
Jake Arrieta (6.13 ERA, 4.01 FIP, 2.12 ERA-FIP)
Arrieta, oddly enough, is Timmy without the velocity troubles. Au contraire, actually; he’s seen a rise in fastball, slider, curveball, and changeup velocity since last year, and though his once-impressive slider has waned in value, bad luck seems to be Young Jake’s nemesis first and foremost. His home-run rate of 1.15 per nine hardly spells confidence for the Orioles’ arm, but it matches the rate he put up over the previous 200+ innings. This go-round, his strand rate and balls in play have been on the wrong side of lucky, so expect a turnaround that’ll make him deeper-mixed worthy (especially on the road, where his FIP is 3.00). Don’t let it be lost on you, though, that he’s always a blow-up risk.
Verdict: To some, a worthy second half rebound.
Josh Johnson (4.35 ERA, 3.12 FIP, 1.23 ERA-FIP)
One thing’s clear after an ace’s June and a fool’s July, and that’s that Johnson’s been quite the frustration. Behold his monthly ERAs: 5.34 in April, 4.41 in May, 1.87 in June and 7.56 in July. His FIP, meanwhile, has been more stable, never jumping over 4.00 and hovering below 3.00 in two separate months. The burly lefty should expect some line-drive regression as his 25.3% rate against is high for any pitcher, especially someone with two plus-value pitches in his fastball and curveball. He has a spacious, friendly monstrosity of a home park (have you seen that “art” that is unleashed during home-run celebrations?), and a track record of success. Chalk this up to a long post-surgery hangover, and put him high on the list of second-half pitchers to target.
Verdict: Buy, buy, buy.
Adam Wainwright (4.42 ERA, 3.26 FIP, 1.16 ERA-FIP)
Wainwright’s practically the same pitcher he was pre-Tommy John, albeit one with a less biting curve and slower fastball. Still, his peripherals are all in line with his previous dominant self: the only eye-catching difference is how often the balls are crawling out of the park. He’s generating a ton of ground balls to a poor-fielding Cardinals team, for one, and has allowed four homers labeled “Just Enough” or “Lucky” by ESPN Home Run Tracker. And now you see the problem with ERA.
Verdict: Like Josh Johnson, but with a better offense.
Worst Differentials
Jeremy Hellickson (3.55 ERA, 5.32 FIP, -1.78 ERA-FIP)
Not a favorite of the stats community, Hellickson’s strikeout to walk ratio of 1.58 is in the bottom ten of qualified starters (among the likes of Ricky Romero, he of a 5.22 ERA, and Ubaldo Jiminez, he of a 5.24 ERA). So how can a pitcher who strikes out few and walks plenty find his ERA on the right side of 4.00? Some proper good luck, and Hellboy has had it: his .253 BABIP is tied for 10th among qualified starters. It is borderline impressive that he’s managed a 3.55 ERA despite his seventeen home runs allowed, but that’s merely a function of their nature: 13 have been solo shots. And to put some icing on the very concerning cake, only two Hellickson-served homers have been of the “Just Enough” variety. Yeah, as if you needed more reasons to sell him.
Verdict: Waiting to blow up.
Ryan Vogelsong (2.31 ERA, 3.73 FIP, -1.42 ERA-FIP)
Think of this as a mutual breakup: you two have had something of a glorious run, yet it’s clear the best days are over. You end your relationship with a mutual respect for and an appreciation of one another, and perhaps even stay in contact and good graces. The obvious key to the breakup is that Vogelsong’s key drawing point, his 2.31 ERA, is aided by all types of luck: batted ball average, line drive rate, strand rate, low home run rate. So, as well-liked as he’s been in the fantasy community this year (for proving the haters of his glorious 2011 breakout campaign wrong), his owners can’t seriously expect the same standard of success as they found in the first half.
Luckily Vogelsong owners have a pitcher with good roto ratios and respectable peripheral numbers; in other words, his owners have a very valuable trade chip to a wide variety of roto players. He’ll be on the wrong side of luck in the second half (expect his ERA to crawl closer to last year’s 2.71 mark by year’s end), but if you get the combination of 1st half Vogelsong and 2nd half Johnson – and you’ll have to be plenty adept to pull off that trade – for a late-round draft pick, you’ll have the tip of my hat.
Verdict: Bid him a sad farewell, and thank him for all he’s done.
Ryan Dempster (1.86 ERA, 3.13 FIP, -1.27 ERA-FIP)
Over the last four years, Dempster has flashed remarkable consistency with his peripheral stats. The range of his FIP marks from 2008-2011 was a mere half run. His xFIP mark – which factors in regressed, league-average home run rates – ranged a mere .07 runs over the four year period. His strikeout to walk rate in the time span was somewhere between 2.33 and 2.65 at every year’s end. The only thing that hopped around was his ERA, which crawled from 2.96 up to 3.65, followed by a 3.85 mark and a 4.80 dud last year. It was any analyst’s dream: Dempster simply struggled with some ill luck, and was a clear turnaround candidate.
No one expected this, though: a scoreless innings streak greater than R.A. Dickey’s, an ERA under 2.00 in late-July, and even pretty WHIP numbers (his career mark, for reference, is 1.43). And while it doesn’t take an expert to tell you Dempster’s ERA won’t hang out near 2.00 for much longer, he may find yet another stroke of good luck in an impending trade. If Dempster ends up in L.A. pitching for the Dodgers, he’ll find himself a very pitchers-friendly home park and in a division that includes the Padres of PETCO Park and the Giants of AT&T Park. Take a page out of Epstein’s book and sell with caution and poise…
Verdict: …but definitely sell.
Follow Nick Fleder, who runs the Fantasy Department at The Hardball Times, on Twitter at @fishfle. Email him at nick DOT fleder AT gmail DOT com.
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