Someone help me here: I'm wondering if this slightly misstates the case. The author seems to conclude that "in order for a hitter to be good enough to get at least 3.1 plate appearances per game in Major League Baseball, he has to possess some skill that prevents him from being unduly penalized by strikeouts" and "hitters who are too vulnerable to the strikeout will get weeded out and thus won’t move up any further than that level."

I wonder if the correlation between strikeouts and offensive production is actually because of a general front-office distaste for players who strike out a lot, meaning only very good hitters can stick around in the Majors if they're whiffing a ton. I can't imagine a team would have a lot of patience with a slap-hitting middle infielder who struck out 160 times a year, whereas they'd be more likely to bear Ryan Howard's Ks since he's hitting so many home runs.

In other words, I suspect it's not "some skill that prevents him from being unduly penalized by strikeouts" so much as it's a set of skills that allows him to advance and stick around despite the strikeouts.

Unless, of course, that's what he's suggesting.

What he's documenting here is a form of selection bias. The only high-K hitters who make to the majors and keep playing are those who have some other offsetting skill(s). And since HRs and Ks are correlated, you can even get a negative correlation in MLB between Ks and offensive performance. Striking out is still a problem for hitters, all else being equal -- but all else isn't equal. Trying to find the relationship between Ks and wOBA at the MLB level would be like studying the relationship between family income and SAT scores, but studying only kids in AP courses -- the correlation will be much weaker than for population as a whole.

But, this is NOT a good example of the Anna Karenina principle, defined in his wikipedia link as "an endeavor in which a deficiency in any one of a number of factors dooms it to failure." In fact, it's exactly the opposite of that. Hitters can succeed at a very high level despite being quite weak in terms of avoiding strikeouts, because they have other skills. There are probably hundreds of minor leaguers who could strike out less than Adam Dunn if promoted to the bigs. But they couldn't out-produce him. Clearly, a strikeout weakness does not "doom" a player to failure.

Man, Hahvahd ain't what it used to be......

What he's documenting here is a form of selection bias. The only high-K hitters who make to the majors and keep playing are those who have some other offsetting skill(s).... Striking out is still a problem for hitters, all else being equal -- but all else isn't equal. Trying to find the relationship between Ks and wOBA at the MLB level would be like studying the relationship between family income and SAT scores, but studying only kids in AP courses -- the correlation will be much weaker than for population as a whole.

Is that what he's saying? Because that's basically what I meant in #1, but I'm not sure that's what he meant.

If you're not considering the fact that taking/swinging and missing at a lot of pitches also leads to greater incidences of Ball 4 arriving before strike 3, you're not really fully studying the issue.

TedBerg: I'm not sure if that's what he meant. But that's what actually happens.

I just don't get the Anna Karenina thing. The AK principle would apply if all players who make it to the majors are pretty good at avoiding strikeouts, so there just isn't much variance. An example of that would be pitchers and BABIP: if you aren't pretty good at preventing hits on BIP, you can't survive in the majors. So the variance is small. But hitter Ks is exactly the opposite: you can thrive despite a glaring K weakness, because of offsetting strengths.

He notes that all good crew athletes are about same size/shape, so maybe that's a good example. But Dunn and Ichiro? That should have tipped him off......

But hitter Ks is exactly the opposite: you can thrive despite a glaring K weakness, because of offsetting strengths.

Exactly. Ultimately, for hitters, it comes down to what you do when you make contact.

-- MWE

what MWE said. With the addition that the more contact you make, the less productive you need to be per contact. If you don't make a lot of contact, you better cream the ball.

Ks depress batting average. The common stathead belief that BA doesn't matter is wrong of course -- it's the main component of OBP and SLG. So, generally speaking, to be successful with a high K rate, you need a good ISO and, preferably, a good walk rate. Otherwise you pretty much are doomed because you're starting from a base of a 250-260 BA.

And my rule of thumb is that the line for possible ML success is an ML K-rate somewhere around 1 K per 3 AB. It's hard to be successful at that rate but nearly impossible if you're worse than that. The issue around minor-leaguers is that if you're K'ing 1 per 3 AB in the minors, you're probably gonna get eaten alive in the majors even if you are putting up a line like 260/360/560 in the minors. That guy will still have plenty of power (ISO) in the majors probably but he's gonna put up something like 220/290/470 and teams aren't too impressed by 290 OBPs these days.

In other words, I suspect it's not "some skill that prevents him from being unduly penalized by strikeouts" so much as it's a set of skills that allows him to advance and stick around despite the strikeouts.

I'm not sure there's a huge difference in those statements but I guess I'd lean slightly towards his. That "skill" is usually smacking the holy crap out of the ball when you do hit it. But Wily Mo Pena is an excellent example of a player who was "unduly penalized by strikeouts." His on-contact numbers were actually pretty impressive but it only added up to an average hitter at best. He would have had to hit the ball, when he hit it, at an historic rate to be a truly productive hitter. Some players have the power/walk skills to overcome the hit to their BA, some don't.

And of course it never hurts if you can play C, 2B, SS or CF. 250/310/400 can still play at those positions if you can handle it defensively. (So could 220/290/470 I suppose but that line is usually associated with a really big guy who can't handle the position.)

Looking at seasons with at least 150 Ks (502 PA min), there have only been 8 such seasons in MLB history.

DeShields at 22, 2B
Jose Hernandez, SS
Ben Grieve, the beginning of the end
Peralta, SS
BJ Upton 2009 -- hopefully not the beginning of the end
Juan Samuel at 27, the beginning of the end
Inge 2007
Donn Clendenon in 1968, back when a 142 ISO meant something! (league average was 98)

Other than Grieve's 760, the next highest OPS was 708, most below 700.

Best performances of this type were Matt Kemp in 2008 (153 K, 290/340/459) and Mark Bellhorn (177 K in 523 AB, 264/373/444). That was a fairly typical Bellhorn season except that he hit 264, not his career average 230. He's another guy who was "unduly" penalized for a lot of Ks -- great walk rate, good ISO for a 2B. Excellent when he lucked into a 260 BA, tolerable for a 2B if he hit 230, often struggled to hit 210. Jose Hernandez is another guy -- excellent glove and power for an SS, tons of Ks, never walked. One of my all-time favorite comps:

Jose Hernandez: 361/598 on-contact, 1 BB per 12 AB (or 13.25 PA), 1 K per 3.5 AB (3.66)
Miguel Tejada: 332/540 on-contact, 1 BB per 14.5 AB (15.9), 1 K per 7.7 AB (8.4)

If Ks didn't matter or didn't matter much, you'd think these guys would be pretty close to one another.

Tejada: 810 OPS, 112 OPS+
Hernandez: 729 OPS, 88 OPS+

Hernandez was a very good fielder -- he had a nice career anyway but get him to a 100 OPS+ and he'd have been a well above-average player (a poor man's Tulowitzki). In general, I figure you don't screw around with a hitter's approach -- if they K a lot and you try to change them, who knows what will happen. Presumably, at the very least, their on-contact numbers go down. But Hernandez is a guy that maybe they should have tried to change. Give him Tejada's on-contact numbers and cut his K-rate just to 1 per 5 AB and his BA is up to 266 and his SLG up to 432, an overall 28 point increase in his OPS and about 7 points in OPS+. Fair enough, if the changes also cause his BB-rate to fall to Tejada's levels, he loses the OBP bump and he gets just the 14 point bump in SLG and only 3 points in OPS+ ... so maybe it's not even worth trying to fix Hernandez.

And that is maybe a demonstration of why "Ks don't matter" for batters. To drop a batter's Ks, you presumably drop their on-contact production and probably their BB-rate. The BA will probably come up, the OBP will stay about the same, the SLG will probably go up a bit (the ISO might go up or down a bit but the overall SLG will probably go up).

And to put Hernandez's on-contact numbers into perspective, Sheffield's are 334/589 and Sheffield had the rep as one of the quickest bats in the league and has a career BA 40 points higher than Hernandez. The difference between them as hitters is all BB and K.

Hey guys, thanks for reading. I just wanted to clear up a couple things. First, to SoSHially Unacceptable, I was aware of BB being a part of this positive correlation. I did run some multiple regression using both BB and K, though, and in that case K was still not negative (it was insignificant), so I continued looking for other reasons.

Second, and more importantly, about whether this is selection bias and NOT the Anna Karenina principle:

You’re absolutely right in that strikeouts alone aren’t a good example of this, but the skill I’m talking about is not really avoiding Ks alone. It’s about preventing Ks from unduly interfering with production. The way I see it, a player who strikes out less than Adam Dunn could still have more of a problem with strikeouts than him. Take Brandon Inge, who strikes out 30% of the time and was below average. A pitcher can neutralize his production through striking him out, while he can’t do that with Dunn.

Now, I realize that this *alone* is still what you’re saying – that it’s the other skills that allow Dunn to succeed, to overcome his K rate, and therefore it’s not the Anna Karenina principle. But here’s why I think it’s still there: Inge is good enough when he doesn’t strike out to be an above average player. If he reduced his K rate while holding all other at bat results proportionally constant (and even if they all got a little worse), he’d be a better player. That is NOT true for guys like Vernon Wells, who had production similar to Inge’s. If they struck out less often, they’d still suck. I realize all of these guys are still good enough to be in the majors, but if you just switch “average” with “replacement level” and find players in the minors who are similar, it’s the same thing. Inge wouldn’t be able to make MLB because he would strike out too much, not because he didn't produce enough otherwise. Obviously he could make up for it by producing more, but Ks are still the biggest flaw in his game. It’s still a strikeout problem, just not one of raw K rate.

I realize from the discussion here that I didn’t make this clear enough, and perhaps I’m still way off base in terms of the way I applied the principle. If you think that’s the case, I hope the data analysis alone still holds up. Again, thanks for the criticism. It's going to help me a lot with this subject going forward.

Well, jumping in front of a train closely correlates with a drop-off in slugging.