Do Southpaws Get a Fair Shake in MLB? Part 2: Pitchers

My first attempt to look at the compensation of lefties in the big leagues focused solely on hitters. I found, contrary to findings in “the real world,” that lefty hitters earned about a quarter of a million dollars less than equally skilled right-handed batters. However, there are few problems with the analysis; the biggest one being that I only used hitting stats and lefties don’t play a few positions of high defensive importance. I can think of some ways to control for this, but all of them are a royal pain. Instead, let’s look at pitchers.

Just like in the analysis of hitters, I include only pure left and right-handed players—no switch hitters or players who throw and bat with opposite hands. I estimate the impact of pitching performance (estimated through strikeouts, walks, home runs, and innings pitched), age, and handedness on yearly salary for free agent eligible pitchers. I used two samples: more than 100 innings pitched and less than 100 but with a minimum of 30 innings pitched. This should roughly capture starters and relievers. I care less about that starter/reliever designation than I do about getting an adequate sample size.

The results are interesting. For the starters sample, lefties earn about $233,000 more than equally skilled right-handed pitchers. This fits with the findings from the general work force. Again, the relationship is not statistically significant, but it’s close, with a t-statistic of 1.55 (p-value of 0.12). This is about 7.5%, which is about half as large as the effect found in the general labor force. I find it interesting that you often hear left starters described as “crafty.” Maybe there is something to it. These guys are deceptive and smart, and have higher opportunity costs outside of baseball. I’d be curious to see the handedness of pitchers turned TV commentators, scouts, instructors, etc.

For relievers, the findings are nearly the mirror image, and the estimate is statistically significant. Southpaw relievers earn about $209,000 less than equally skilled right-handed pitchers, which is similar to what I found for position players. Hmm, maybe this has to do with LOOGY duties of lefty relievers. Because many left-handed relievers are used only against other lefties there are a lot of marginal pitchers who hang around. This may reduce the bargaining strength of each other because teams can just say, “look, if you don’t sign this contract I’m just going to bring up some random kid from triple-A or sign Mike Remlinger.” And because there are very few ROOGYs, marginal righties are more likely to find a real job if they are on the margin. OK folks, this is what is called a stretch, but it seems somewhat plausible.

I post the results below. Feel free to add comments.

Var.	Coef.		T-stat
K9	$408,358	7.29
BB9    	-$294,948	-3.78
HR9    	-$865,822	-3.65
Age    	$371,375	1.59
Age2	-$4,417		-1.27
IP    	$8,410		5.37
Lefty	$230,654	1.57
R2    	0.47	
Var.	Coef.		T-stat
K9    	$219,657	6.92
BB9    	-$186,071	-3.74
HR9    	$269,649	1.81
Age    	$645,741	2.52
Age2	-$9,295		-2.43
IP    	$8,468		2.41
Lefty	-$209,337	-1.98
R2    	0.25
(Constant and year effects not reported)

7 Responses “Do Southpaws Get a Fair Shake in MLB? Part 2: Pitchers”

  1. Ted says:

    A couple thoughts on the starting pitcher sample. The southpaws may be better, and therefore more valuable, than your analysis suggests:

    1. Your measure of pitcher effectiveness ignores balls-in-play and baserunning. Lefties are widely believed (including by me) to be superior at controlling the opponent’s running game. They might also be better at balls-in-play. Without getting into a whole DIPS discussion, a reasonable hypothesis is that they tend to face more right-handed batters and may, therefore, surrender fewer infield hits.

    2. There may be value in having a diversity in the handedness of a team’s starting rotation. Managers do like to mix righty-lefty-righty in the starting rotation. Teams like to have at least one and usually two lefty starters. The theory is that there is interaction between starters such that having two lefties makes your righties more effective by, for instance, keeping the opponents hitters “off-balance” during a series. This may be an example of market failure though I tend to think there are more interactions among players than traditional sabermetics assumes.

    Great work.

  2. Dennis says:

    I would break the relievers down into closers and non-closers for several reasons–difference in perceived value, usage (closers can’t be LOOGY or ROOGY). At one time there was also a bias against leftys as closers, though it’s faded.

  3. flournoy says:

    I have no trouble believing that a left handed pitcher makes more money than a right hander of equal talent. Left handers have more market leverage because there are fewer of them. Every team wants to have a lefty or two in the rotation and two in the bullpen, but there probably aren’t that many qualified pitchers. Teams are thus convinced to carry a marginal left hander for no reason other than his handedness, even though better right handed pitchers are available.

  4. lchen says:

    Would you count Billy Wagner as a Lefty or a righty with your system since he only throws and bats lefty b/c of a broken right arm he suffered when he was younger, making him pitch lefty but naturally be a righty?

  5. JC says:

    Wagner is a lefty in the sample. The L/R distinction is tougher than we often make it out to be. My father writes with his left, but throws and bats right-handed. I guess the standard for the real world is which hand you write with (I assume Wagner writes with his right) but I don’t have this data. However, I suspect the correlation between bats/throws left and writing is between 0.9 and 1.

  6. 4Seam says:

    Lefty batters are usually pull hitters.

    They don’t face much left-handed pitching for one, and only get AB against righties.

    That stunts there development.

    By the way, if anyone wants to play Fantasy Football with some really/pathetic Braves fans including me, then go to, look up the “Memorial” Game Thread and for Smitty’s FF post. We need some more teams!

  7. lchen says:

    I think it’s pretty interesting that, although the statistic isn’t too solid, relievers who give up more home runs per 9 innings get paid more. I’m sure there is some confounding factor involved (or maybe just a typo) but even so it’s pretty interesting to see.