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Lanchester, use and abuse thereof.

Wiggins dropped by, to see what we were chatting about in the 12 October H&I post where Ry linked to Opposed Systems Design.

He left this comment.

Thanks much for the link.

I was being a bit harsh, so let me clarify myself.

Mathematical laws of chemistry describe immutable dynamics of the physical world. I question whether combat has any similar immutable dynamics that are waiting to be mathematically modeled. The difference lies in the thinking adversary inherent in war, as opposed to the stable relationships of chemistry.

Maybe the mathematics of dynamical systems offers a way to account for this - I think this is why chaos and complexity theory get folks so excited - but I haven't encountered it yet.

My second post didn't claim Lanchester wasn't useful; it argued that it was being used in situations where it wasn't appropriate. The question wasn't 'is Lanchester useful,' it was how often is it useful and in what cases? I was voicing my concern that Lanchester is rarely useful and sometimes used inappropriately. Not because it helps, but
because it's something concrete we can work with.

... of course it would have helped my argument if I had, I dunno, had an actual example to back that up...

I started to answer in email, then decided - "Hey! I've not done a geeky wargaming post for a while! No time like the present..."

I was voicing my concern that Lanchester is rarely useful and sometimes used inappropriately. Not because it helps, but because it's something concrete we can work with.

... of course it would have helped my argument if I had, I dunno, had an actual example to back that up...

I can help, and give you an example.

I didn't weigh in too much on this discussion, as it cuts to the heart of what I do for a living, and there are issues of classification, employment, and intellectual property rights that make me stand mostly mute.

But I will say that Lanchester can be useful, at it's most macro and most micro levels, when you are comparing forces which can be generally assumed to be at parity on the issues in contention. Oddly enough, that's pretty much all that Lanchester was proposing.

Such as modeling force-on-force from a hardware perspective, to examine the effects of the hardware. It can also be useful for examining organizational structure and doctrine - again, essentially positing a peer opponent. If your hardware wins, and your doctrine wins, and your hardware *and* doctrine wins in a Lanchester world, you are going to probably fare well, within the confines of entropic events and effects.

Of course, that's a very narrow set of bounds. And the consequences of bad assumptions about parity (and *your* basic competence and morale) are huge.

So, when the Army designed it's first sims for that kind of thing, it used Lanchester because we were assuming that at most levels, the Soviets, from a morale and basic professionalism level, were peers. So, we wanted to know if our tanks, tied to our doctrine, would prevail on the North German Plain (i.e., Fulda Gap). And if they didn't, what tweaks or wholesale changes would make a difference? And that sort of thing was generally confined to analytical work on those levels. Examples are VIC at the macro level, and Janus at the micro.

Of course, problems surfaced. Trainers wanted sims too. And if you've ever sat down at a Janus workstation, it looks (especially back in the day) pretty clunky, and the graphics are nothing to write home about, but it sucks you in almost immediately, if you're a trainer or wargamer.

I was in on the leading wave (heck, I helped lead it, at my level) on integrating those sims into training.

And, of course, one of the first things we did was try to build scenarios of historic battles. And found you had to tweak the crap out of things (something that board game designers like Dunnigan and crowd have know for decades) to generate historical outcomes. Not only because two regiments of muskets is *not* the same thing as Chamberlain's 20th Maine and Oate's 15th Alabama, but the digital terrain is not the same as the historic terrain. The man matters, and terrain representation is critical.

It's *not* when you're trying to compare tank vs tank, doctrine vs doctrine, on common terrain (the digital battlefield).

Danger, Will Robinson! Danger!

So Wiggins is correct - you have to understand your tool. One of the things I did as the Chief of a simcenter was sell my facility as a C2 trainer. Because you can use a Lanchester sim to drive training where the focus of training is the military decision making process. But quickly, commanders seized on it as a wargaming tool for things like NTC rotations, and it was a never-ending fight to get them to understand that the digital terrain does not exactly match the NTC dirt, and micro environment matters in fights at that level. That a plan that works in sim at Fort Sill, or Fort Hood, or Fort Riley, isn't guaranteed to work at Fort Irwin, on the real dirt, against the real OPFOR. But that the practice of your staff planning processes would pay off. You'd still need to make your plan based on the actual ground when you got there.

I promised an example of using Lanchester inaptly.

Desert Storm. Remember the predictions of 10K casualties? Say hello to my little friend, Janus. The modeled Iraqi Army was using soviet-derived equipment, with a modified 1950's British doctrine, fighting a defense from prepared positions where they'd had time to really dig in. And they were being commanded by a competent Red force team. Against a competent Blue team. And while we won, we got hammered doing it, because Lanchester is a bloody algorithm. And it makes a huge difference, when your data for your tanks is conservative - and you can actually kill a couple hundred meters farther out than you were able to in sim (as we found out when they modeled the Battle of 73 Easting and had to tweak things to match the historical record).

If you're going to err, err on the side of caution, I say. But you have to understand the limits of your hardware, architecture, design intent, and algorithms as you make choices.

There is much work that has gone on since then in building the mission planning and rehearsal tools, and they're pretty mature and robust for naval purposes and for aviation, both of which can largely ignore the effects of micro-terrain, because the ocean is flat, and the ground is effectively flat to fast movers and many helo missions, and is platform-based, which is much easier to model from an AI perspective.

Ground combat, with micro terrain and micro people, is still an on-going and evolving challenge.

And when you try to model the Current Operating Environment, boy-o-boy is Lanchester not your friend. But it was never meant to be, either.

So yes, I agree with Wiggins - people with the best of intentions, especially under a "I have to have it now" imperative, can badly mis-use Lanchester-based models, to their grief.

Okay, time to put this to bed and head for the BDE TOC. Have fun chewing on this, I probably won't be able to respond to anything until tonight.

14 Comments

Say hello to my little friend, Janus. Our then-Battalion CO gave ten of us Fulltimers a briefing on the horrendously horrendous, triangular forts within triangular forts the Iraqis had built and the layered minefields and AT ditches protecting them before he came out with the infamous 10K casualty estimate. He looked totally dumbfounded when I raised my hand and said, "Arc Light. The only casualties you'll have will be from guys falling into the bomb craters." "They won't use B-52s. They can't survive in the High-Threat Environment of missiles and MiGs." "They did pretty well over North Vietnam." He finished the briefing and spent the next half hour on the phone -- "Well, plug it in as a DivArty linear target!"
 
While I was an O/C at the NTC during Desert Shield we built the Iraqi obstacle belts, manned 'em with OPFOR, and then attacked 'em again and again, until we developed ways to reduce them with literally no casualties. We made a movie about it. And the guys who would actually have to do it watched our movie, and threw up, because it involved a *lot* of getting to within hand-grenade range. They promptly went and developed ways to do it that allowed for much more stand-off, and utilized weapons in way we didn't think of, because the safety considerations of doing it live, force-on-force kind of turned off that part of our brains. So, while I stand by the approach we took and the solution we came up with - it's most salutary was to keenly focus the minds of the guys who were going to have to do it for real on the fact that "There's no way in hell we're going to do it that way!" and they developed the TTPs they did which were, I freely admit, much better than ours. I learned more about training to fight in that event and it's aftermath than the entire rest of my career.
 
And I wonder how many people get past the first paragraph of this post without going into MEGO* status. Heh. This is what this place would be like if I hadn't hired Tuttle. Oh, yeah - yer check's in the mail, dude. ;^) *My Eyes Glaze Over
 
Yo, John -- you sent me ry's stale cheez curls. I'm supposed to get the stale chex party mix...
 
Have fun chewing on this, I probably won't be able to respond to anything until tonight. Wha' hoppen, the TOC Ticks toss you out early? "Just put Extended Range Tanks on the Predator and cycle the B-2s in every fifteen minutes, then bring in a couple of MD500s with some MPs to corral the survivors. Tuttle sez that's how *he'd* do it." "Get. Out. Now."
 
Actually, I'm pleased to find that the local installation no longer blocks the Castle. I've won *some* fights. And we're in a "Oh, gosh, the wrong software, the one with the reduced functionality, is what we loaded on your machines. Darn it!" Our response in not printable, as it would violate the Rulez in several dimensions.
 
...the one with the reduced functionality, is what we loaded on your machines. Tell them to upgrade the 2.75 inchers on the MD530s to Hydra 70 (Mach 3+ and they're almost as accurate as gunfire) -- don't let 'em tell ya they can't.
 
My work is done. I have returned John to proper geeked out form without having to use a polymorph other spell. My EXP please. Now if I could just get Armorer to give me a reading list on this field(sort of a beginners course) I might shut up for a few months, wouldn't that make you all happy?
 
Chill -- I FedExed the cheez curls.
 
reinforcing (once again) the use of the proper tool for the proper job. stack the forces down the alleys when you draw the COA cartoons and do the math for the comparison and the decision matrix, always realizing that the cartoon and the math and the matrix are the tools. it's soldiers and units that will do it for real, and the paper version is never as good as the real way it shall unfold. ahh... Janus. and Artbass... the dank brink warrens of Leavenworth and the stuffy attic of the Abrams Bldg in Frankfurt. good times, good times.
 
"Polymorph other spell"... Buahhawhawhaw... Good luck, it won't work and I know from personal experience. Now, while I won't say John 'cheated' as a DM, I will say that the results of certain encounters WERE predetermined. As the smoking ashes of a character of mine can attest. Oh, I'm sure there will be denials, but I know better. And as for EXP? Good luck, John was a miser.
 
John was a miser. Yeah, right. That's why Bruce had a Golf Bag of Holding. *I'm* a Monty Hall. Feh. Bob Barker was my role model, and you know it, hoser. Yer still whining, 30 years later, about Bruce teleporting himself into a solid stone pillar in the caverns of the Frost Giant Jarl? Or izzit the time that he just flamewalled everything, and you were invisible, slinking around like the thief you are, and got whacked? Hmmmm. Methinks you should be annoyed with... Bruce. 8^ ) Even better - after 30 years, I remember all that, because watching you die was sooooooooooooooooo much fun!
 
For what its worth, a noted School of Advanced Military Studies professor with a bent toward physics terms (like "poor dead" Karl had) told me that Lancester equations were OBE when they were devoloped. He thought they explained Napoleonic War and to a certain extent the American Civil War but they did not explain the Russo-Japanese War and certainly none since WWI.
 
I just did a Rule 34 search on Google and got 323 hits for the string, Lanchester Operational Research porn.