The positional adjustment is based on both relative offensive production and interchangeability (between similar positions where we see people move) because both impact the effective talent pool at each position (more on this later). This doesn't mean the positional adjustment is a reasonable proxy for how players might fare defensively when they are moved out of position and that's also not what WAR means. Also, the positional adjustment for catchers is the highest despite the fact that most catchers' secondary position is 1B and they typically don't put amazing defensive numbers at 1B that the difference in positional adjustment might imply. Then why is the positional adjustment so high? Because catchers as a group are bad hitters.

For example, if there's an abundance of middle infielders that might put up around 0.0 WAR, that's the replacement level (and this is what the positional adjustment is designed to approximate). Just because a group of left-handed DHs that might put up 0.0 WAR at DH would actually put up -5 WAR on average if asked to play SS, doesn't mean WAR should reflect that in any way.

I think you once read about people using defensive data for players that moved positions and using that at least partially for positional adjustment and formed this opinion without really thinking through what's going on. The point isn't about figuring out how a random other ML player would fare at SS - that has no bearing on the replacement level for a SS at the major league level. The point is that interchangeability between positions corrects for the issue that using pure hitting data would create - what if some positions just have more talent than others due to the athletic ability required to play the position or just due to dumb luck? Using both ensures that we correct for this bias and also properly account for how interchangeability impacts the effective talent pool. Again, this doesn't at all mean all positions are interchangeable or the positional adjustment between positions that aren't similar at all is reflective of how a given player might do when switched.

Consider this hypothetical - if most players' WAR won't change when you switch their position, since their defensive performance will largely change according to the relative positional adjustment, then does that means we can literally take a team, put starting position players in random positions and have roughly the same quality defense? Of course not.

So just to clarify where this goes wrong, let's say a typical player that plays both 3B/SS is 5 runs better at 3B vs SS and a typical player that plays both 3B/1B is 15 runs better at 1B vs 3B (just using FanGraphs adjustments). This does NOT mean a typical 1B would be 20 runs worse defensively at SS (he'd be worse by more) and also this does NOT mean a typical SS would be 20 runs better defensively at 1B (he would improve by less).

There are two different reasons for this - the first, the easy one, is that players are generally put in positions where they have the skills and the body type to succeed and this isn't identical across positions. The second is that there are far more opportunities for difficult plays at more premium positions - this is why we put better defensive players there in the first place. This means if you put an average 1B at SS, things get much worse than your positional adjustment might indicate. But if you put an average SS at 1B, you don't get anywhere near the same benefit because the opportunities just aren't there.

To illustrate this mathematically - say that the only difference between these positions is the number of difficult plays (100 at SS, 50 at 3B and 20 at 1B) and each play is worth one run. Let's also assume that the average shortstop makes 100% of these plays, the average 3B makes 80% of these plays and the average 1B makes 40% of these plays. And let's also assume that the average player that plays both SS/3B makes 90% of these plays and the average player that plays both 3B/1B makes 60% of these plays.

This means the average player that plays 3B/SS is

10 runs worse than an average shortstop (90 vs 100 at SS)
5 runs better than an average 3rd baseman (45 vs 40 at 3B)

For a positional adjustment of 15 runs

The average player that plays 1B/3B is

10 runs worse than an average 3rd baseman (30 vs 40 at 3B)
4 runs better than an average 1st baseman (12 vs 8 at 1B)

For a positional adjustment of 14 runs

So the positional adjustment between 1B and SS in this hypothetical is 29 runs. But what if you put an average 1B at SS - how much does he get worse? He'd be 60 runs worse than an average SS (40 vs 100)! What if you put an average SS at 1B? He'd be just 12 runs better than an average 1B (20 vs 8).

Your new MLB OPS leader is Aaron Judge.

This is an inner-circle HoF peak we are witnessing.

Ha yeah so it's exactly as I suspected: you have no idea how WAR actually works. That's not surprising because few people do.

I would still be on my way to 3rd right now, moonwalking after cartwheels between 1st and 2nd base.

I'm definitely one of those extremely few people that do understand it - I've been following this for a long time and was quite familiar with the concept long before WAR was invented (the concept of valuing players by comparing them to replacement level precedes WAR) and have even discussed (some over email, some in person) some of the underlying statistical concepts with earlier sabremetricians who you might know if you are familiar with the history of how we got to where we are with respect to player evaluation.

I'm also confident that I've adequately explained the concept of positional adjustment at this point to you - curious if this is just your way of avoiding embarrassment by pretending that you won an internet argument (in that case, congrats!) or if you genuinely ended up completely misunderstanding WAR in a way that makes it difficult to understand what I've laid out here.

LOL

Yeah Aaron Judge is in that zone right now. Amazing to witness.

Still cannot believe that the Yankees are playing him in CF though and potentially jeopardizing that HoF career.

Curious if you even know what types of players can or cannot play certain positions? It almost feels like you don't have a baseline understanding of the game at all:

But then if you literally don't care enough about baseball that you'd say something like that, why do you have a strong opinion on what WAR is? That's what I don't get. I thought maybe you were some kind of a math nerd that was into stats but not the game itself, but then in that case you'd understand the hypothetical I laid out.

Is there evidence that playing CF is more taxing than RF?

Obv it's harder, but is it worse on the body? FWIW Judge's injury last year doesn't happen in CF.

I'm gonna need for you to write another hundred paragraphs of diarrhea before I consider responding.

lol'd


I don't even read that stuff. Please no one report the posts as a joke so I have to.

So WAR is designed to be a comprehensive stat to determine how valuable a baseball player's production has been. And it does so by comparing each player's production to a hypothetical "replacement-level" player, which is defined as how good players that are relatively freely available might be.

Well that's the concept, but to compute WAR in reality, we have to put some numbers - how good are these replacement-level players at each position? Instead of trying to define this independently, basically all versions of WAR does some variation of this: they take average batting production, apply some discount (since replacement players by definition aren't as good as average), then apply positional adjustment and apply defensive performance. So WAR is:

Player's Offensive Production - Replacement Level Offensive Production + Positional Adjustment + Player's Defensive Production (above average).

So the idea of positional adjustment is tricky because it's trying to deal with the fact that equivalent offensive production at certain positions are more valuable than others, due to scarcity. Some positions are inherently harder to play and also certain positions exclude certain types of players altogether. 3B/SS are practically impossible to play for left-handed throwers at a high level and 2B/C are in some theoretical sense playable for lefties, but in practice this doesn't happen at higher levels of competition.

So one might ask, could we just use the average offensive production at each position? The problem is that this is highly volatile - you're penalizing players that happen to be playing at a loaded position. Also, it's fundamentally unfair because some positions might naturally have better athletes. For example, what scouts look for in SS and 2B has historically been similar, with the one key difference is that for SS, you want a better arm. But arm strength has some correlation with power, so you might end up in a situation where SS on average are better hitters than 2B in any given year, simply due to teams putting better overall athletes there, even though everyone would agree that 2B is a lot easier to play.

So people also looked at the relative difficulty of positions - for a set of players that switch between comparable positions (for example, 2B & SS, 3B & SS, 3B & 1B, CF & LF, CF & RF) and how do their defensive performance look like, to make sure that we don't accidentally penalize athletes playing a more difficult position simply because the position has better overall athletes playing them. The important thing is that this adjustment is not designed to predict how you would do if you were to move position. There's some interchangeability, but they aren't entirely fungible. There are also limits to this, so the positional adjustment has historically incorporated both this as well as relative offensive production.

For example, a SS can generally play 3B and 2B. a 3B can generally play 1B. SS/3B/2B can generally all play LF/RF. CF can generally play LF/RF. But there are a lot of position-specific skills, not to mention the whole left/right thing. Catchers generally won't really be good anywhere, though they can usually be good-enough at 1B. A lot of athletic, but smaller players can be adequate at 1B, but won't be elite as the positional adjustment might suggest.

But I think Lawnmower Man is trying to say that the positional adjustment is some sort of an effort at estimating how a player might do when changing positions:

But it's not - that's not the question it's designed to answer, but rather the other way around - some level of interchangeability does impact the position scarcity and the actual value of production. For example, even if the average SS hits better than the average 2B, if the average SS can just be moved to 2B and his defense would improve and the average 2B being moved to SS would see his defense suffer, the same offensive production is still more valuable at SS. And the replacement level should reflect that. But the converse is not true - simply knowing the positional adjustment says nothing about how a player might do when they switch position. And the idea that WAR as a model says that an average fielding left-handed 1st baseman would be around 20 runs below average as a SS because that's what the positional adjustment is - I don't really know what to say, that's just ridiculous.

Are you the mod that recently emphasized the importance of following the no-personal attack rule?

There's just a lot more to do - not only are more balls hit to CF, CF has to back up both LF and RF on every play and they are also at a higher risk for collision.

Also Judge's injury from last year was a freak injury, but the outcome is that his big toe require constant maintenance. I can't imagine running a ton at full speed has zero risk in terms of aggravating that injury or causing issues elsewhere in the lower body. And there are a lot of years left on that contract.

The other thing is CF/LF/RF is all reasonably interchangeable and unless you're terrible or elite (and Judge isn't either), your value should not depend a ton on playing a particular position. So why risk any of this?

Well this year Judge is playing CF to accomodate Soto.

Soto is the Yankees' worst outfielder, and Yankee Stadium has a bigger LF than RF, so Soto is playing RF to hide his below-average range.

And Soto can't DH as long as Stanton is still hitting well enough to be on the roster, which currently he is.

I doubt Judge is the CF in 2 years. The plan is for Dominguez to be the long-term CF.

Why can't they swap Verdugo and Judge though?

Yes.


Please pinpoint the personal attacks made, because I don't see any.

I didn't say anything about you making personal attacks - why did you assume that's what I was referring to?

It's a logical progression.
Thanks for baiting me and making me waste my time. Now I know what it's like to read one of your multi-paragraphs posts.

I'm making you waste your time?

This is also a very strange comment from someone who literally used to write fanboy replies talking about how great some of my earlier multi-paragraph posts were. I mean you do you and I don't really care, but it's a bit strange.

Probably just familiarity.

Prior to this season Judge had never played LF while Verdugo had done it a good amount. Judge since 2022 has played a decent amount of CF and he's not bad.

Verdugo grades out a bit worse in CF actually. He's certainly no Harrison Bader.

Yeah, you're right that this is the reason, but it just seems a bit short-sighted - in the long run, there shouldn't be any reason why swapping Judge and Verdugo should lead to a worse outcome, though in the short-term, things like that matter. Also, I think the Verdugo trade happened basically at the same time as the Juan Soto trade, so it feels a bit self-inflicted as well.

Again, I'm probably overreacting a bit here, but I'm (perhaps overly) sensitive about athlete health stuff and it bothers me a bit.