ssivark 5 years ago

Agree broadly with everything in the article. However, I have one point to add:

> Physical models that reproduce behavior are limited by the physics of the world, while computer models have much looser bounds.

This is also one of the weak points of computer modeling. The outputs are strongly influenced by modeling assumptions, and without feedback from reality, one can easily be deluded towards wrong models. The computer simulation encodes the map not the territory. This is particularly true in hard to model fields like economics & finance. As long as one appreciates that, computer modeling is a powerful tool.

Regarding what would make modeling more accessible to computer users, I think the answer is an environment where users have access to the full live system (few boundaries) and can tweak it in real-time, with right feedback loops. Eg: Smalltalk, Lisp.

  • btown 5 years ago

    "All models are wrong, but some are useful" - https://en.wikipedia.org/wiki/All_models_are_wrong

    • AllegedAlec 5 years ago

      I like how Paulien Hogeweg phrased it too: "thinking in the most interesting simplification" [0]

      I always thought the 'but models are wrong' is quite a weak excuse. Newtonian physics is a wrong model of how the universe works. Using it though; we put a man on the moon. Einsteinian physics are incomplete, but it allows us to use satellites moving at roughly 10KM/s to pinpoint our location to within a few metres.

      A model's usefulness is not about how accurately it describes what is happening, but about whether it describes what happens at a certain meso-scale accurately.

      [0]: http://www.labtimes.org/labtimes/issues/lt2011/lt07/lt_2011_...

      • phkahler 5 years ago

        >> Einsteinian physics are incomplete, but it allows us to use satellites moving at roughly 10KM/s to pinpoint our location to within a few metres.

        Funny. I know how GPS works and that knowing the SAT locations is critical, but I never thought about how fast they are moving. They need to transmit their own position and time with great accuracy. In particular, don't they have to transmit their time and position at the time of transmission? That is a more interesting problem than I realized.

        • PeterisP 5 years ago

          GPS satellites aren't really transmitting their location at any particular time, they're transmitting the so-called ephemeris and almanac data that has information about their orbits so that you can calculate their position at the time of transmission.

    • nbeleski 5 years ago

      As someone who have computer modelling as a core of my research it makes me happy to see this quote mentioned here.

      People on other science forums are generally fast to dismiss computer models as 'unrealistic' and 'non-representative', disregarding their utility.

      For those interested in models I always recommend looking at Schelling's segregation model for starters, the premises and conclusions drawn from the experiment are quite interesting.

      • jerf 5 years ago

        For myself, whenever I read about someone's new model and their predictions, I'm always looking to see what their model was verified against. If they've got a model, and it is verified to touch reality in some place we can check it, then I'm willing to at least listen to what the model says about where we can't touch, see, or test. It could be wrong, but it's at least the start of a conversation.

        But if it's been verified against nothing, I don't have much interest in it.

        Some examples of that include almost every model that claims to describe some element of human social interaction, which never seem to be checked against anything real that I can see, and I recall once reading an article and paper on modeling exoplanets and their likelihood of having life on them (or the likelihood of it being hospitable, not sure which) that flew so far beyond our science and data that the peer reviewers should be ashamed they ever approved it.

        (Of course, if you want to publish your unvalidated model as an interesting piece of math, go nuts.)

diydsp 5 years ago

Recommend adding (1996) to title. That doesn't take away from it, it just shows how prescient the thought was.

  • folli 5 years ago

    It also explains why all the links are dead

  • Animats 5 years ago

    Yes. It goes further back than that. That's what Alan Kay thought Smalltalk should be for. Read "Personal Dynamic Media".

    Going forward, there are the persistent shared modifiable virtual worlds, from There to Second Life to SineSpace and beyond. There are many good 3D CAD systems now, and the pro ones have some simulation capability. There's Minecraft and its imitators.

    We have the capability, and sizable numbers of users. It's not mainstream, but it's in wide use.

  • antfarm 5 years ago

    Around 1996 was the hayday of Artificial Life and Complex Adaptive Systems research and (agent-based) computer simulation of living systems, including ecological, social and economical, was a very common topic in popular science publications.

  • rchaud 5 years ago

    Yeah, when the page first loaded, I thought somebody actually took "motherfuckingwebsite.com" seriously and built a raw HTML page with no margins or padding beyond the browser defaults.

zokier 5 years ago

It is a shame that the field is pretty undeveloped still after 20 years. Only recently there have been popping up few consumer CADs (fusion360/onshape), but those are still quite limited and of course do not satisfy free software user like me. Setting up decent physical simulations seems yet another whole endeavor even if you got your model done. There are few physics engines available, but using them seems to require fair amount of work even just for basics. Then comes the social sharong aspect that the article mentions as "Shared federated simulation environments". While I don't think that we need such fully immersive shared environment that the author envisioned, just being able to share models and simulations for exploration on the web would be nice. Being able to get nice photographic-like visualizations would be then the cherry on top this whole thing.

  • mojomark 5 years ago

    >>(fusion360/onshape), but those are still quite limited and of course do not satisfy free software user like me.

    Fusion360 is free (1). I used it for a while; though I didn't get into all of the features so I didn't really explore the physical simulation capabilities in depth, but I know it's supported to a degree (2). I'd imagine the FEA engine isn't as rigorous as paid software like say, Autodesk Inventor or Solidworks.

    As someone who does a fair amount of 3D modeling, I've always thought sketchup was on the right track. It's also available in a free version of course, and the 3D warehouse has a ton of pre-made models in it that I use all the time.

    From my experience, I would say the community-built sketchup plug-ins available are decent, but definitely hit-or-miss. I've never found a good (i.e. non-buggy and well-supported) 'physical simulation' plug-in for sketchup, but I haven't checked the plugin store in a while. That, and some plugins require sketchup pro, which isn't free. In the free software domain, I'd say basic Sketchup is good for quick mock-ups, whereas Fusion 360 can be used for higher precision modeling.

    1. https://www.autodesk.com/campaigns/fusion-360-for-hobbyists

    2. https://www.udemy.com/fea-simulations-with-fusion-360-static...

    • qaute 5 years ago

      Usually, CAD programs are written for just one of several domains, outside of which they don't work as well:

      - Fusion360/SolidWorks/Onshape/Catia/NX are engineering CAD programs. They are designed to make geometrically (relatively) simple parts with exacting dimensions (think vector SVG vs raster PNG) that will fit in mechanical assemblies with other parts. Models (e.g., airplanes) are often simulated for strength (FEA) and fluid flow (CFD). There are no good open source versions (FreeCAD is trying).

      - SketchUp/AutoCAD are for architectural and civil purposes. These create buildings, which often have even simpler geometric features but multiple floors and plumbing and electrical runs and HVAC and other layers. I don't know too much about these.

      - Blender/Maya/3dsMax are for "artistic" purposes. They can sculpt very complex shapes from triangular approximations, but are can't hold exact dimensions very well (raster PNG vs vector SVG). They are used for computer graphics (movies, games). I'm not an expert in these, either.

      I tend to design robots with Fusion, and it's definitely better for my purposes than SketchUp (no easy watertight meshes, assemblies, simulation), but know people who work in different domains who therefore use other programs.

    • zokier 5 years ago

      > Fusion360 is free (1)

      I do enjoy the occasional beer, but it is no substitute for liberty; that path would only lead to alcoholism

  • cr0sh 5 years ago

    I'm not sure that this would be useful to you, but have you seen or played with VPython?

    https://vpython.org/

sevensor 5 years ago

I've had a lot of fun with agent-based and discrete event simulations. Hook it up to a visual and it's basically a game. Writing a basic simulation engine is also a lot of fun. Simulation is also the only application where I've felt comfortable with classical object-oriented modeling. I always find that object oriented programming forces me to deal with a lot of emergent complexity, but when you're doing simulation modeling, emergent complexity is the whole point.

  • gglitch 5 years ago

    Sounds awesome. Can you say more? What languages or environments, what kinds of things you're modeling, other writeups?

    • sevensor 5 years ago

      NetLogo is fun for toy agent-based simulation models. It includes visuals. For discrete event simulation, I recommend SimPy. If you like animations and you're willing to trade some personal info for free stuff, Simio has a free version that supports mixing discrete event and agent based simulation.

      Edit: I realize I only answered about half of your question. I was in grad school when I did simulation modeling, this was about 5 years ago. I was working on modeling industrial processes. Simulation is great in that context because at a certain point queueing theory breaks down. I can't tell you how many talks I sat through that derived exciting conclusions from the assumption that all arrival processes are Markovian.

platz 5 years ago

> The fog surrounding economic projections, and the other uses and abuses of statistical evidence in politics, might lift at least a little.

The perpetual historical failure of academic economic modelers is a counterexample to this line of thinking; to think non-academically trained folks would fare better is laughable

  • Nasrudith 5 years ago

    It might be good for thinking critically however. That could result in a technical truth - if nobody is fooled by models then they won't be used to deceive. If everyone can pick out and point to what is missed or inappropriate models it could and emerging absurdities. I suspect in that regards it is more a way to teach critical thinking.

    The informality could be a boon - less reason to stick to the rules of tenure knifefighting.

  • trentlott 5 years ago

    I mean, this was the essential point that brought about chaos theory, right?

    Rounding wind speeds down at the force of a butterfly flap caused significant deviations for known weather patterns.

    Having people half-ass assumptions because they read about a supply/demand curve once and can scrap DJIA data in order to gamble their 15k savings is unlikely to be widespread, but definitely something to consider if that is your argument.

    However, it would still least breed familiarity. I take your point that this will probably not help things and...well, I guess I've run out of steam in my own comment.

    Ignorance is bad, and staying in ivory towers will end badly. The obvious route for education will likely only foster arrogance and cynicism. What's the third way? Make everyone read Kant and write "Marx was a philosopher, not an economist" 100 times?

llamataboot 5 years ago

I'd love to see more "gamey" and fun platforms for agent-based modeling (Sims, but with different types of goals to tweak!) and something for system dynamics modeling.

There's been a few runs at both, but for how poor human brains are at intuiting things about non-linear systems, and how desperately we need to understand them, more things in this area would be great!

  • troquerre 5 years ago

    Factorio is a great game that teaches system dynamics without having that as an explicit goal

Theodores 5 years ago

VRML became really good a couple of years after this with SGI's CosmoWorlds. I built some incredible things with it, with my actual sister as if we had gone back to childhood with the LEGO bricks out. In fact my sister's well paid career is entirely due to how impressive the VRML that fitted on a floppy disk was. Funny to think that you also applied for jobs by post back then.

Admittedly the texture rendering was not up to modern gaming standards but everything worked and existed on a beautiful imaginative plane - much like how a little bit of imagination is needed with LEGO.

But then we realised nobody else was on the trail. Our models were far in advance of anything published online. Only the SGI demos were cooler than what we had come up with. Then there weren't many of those beyond the demo disk that came with new SGI machines (and needed the power of an SGI machine).

The tools - Cosmoworlds - were fantastic and not hard. I particularly liked the audio aspect, being able to have different music play in a scene and for the stereo to move around as you explored a scene. If I was a musician then I would have wanted my album played that way.

But no musician thought to put their traxxx in a 3D virtual world, online for the world to hear. They had distribution in those days so the required VRML viewer could have been distributed on CD to solve the problem of that ten minute download over dial up.

3D then became the cottage industry that it remained, only done in games companies or by specialists doing things like oil exploration, CAD or other things like TV adverts. Despite the wonders of CosmoWorlds it never became this accessible thing that people wanted to play with in a Lego like way.

After my sister and myself pushed VRML so far my sister ended up working in a world where the interactive exhibits she was to be building for one of the world's greatest museums would only ever be flat and two dimensional. The portfolio of awesome interactivity that got her the job never made it past the bureaucracy, committees and bullshit of the regular world. It was a glimpse of a future that was never going to happen, a high note of creativity to never be reached again. We downsize our dreams, from 3+ dimensions to 2.

The problem wasn't us or SGI's CosmoWorlds. It was everyone else. We are not that adventurous as a species. On a given day the finest mountain tops with the most awesome views only have a small amount of people there, not seven billion people. Even though getting there needs no more effort than putting one foot in front of the other for half the day.

vinceguidry 5 years ago

I wonder if there's not a more basic reason for the observations of the author. When I code as a hobby, my main goal is to make sure that no effort is wasted. I get precious little free time to hobby code as it is, so every minute spent in front of a text editor that's not driving forward to the desired goal feels almost physically painful.

The last thing I want to do in my off time is fiddle endlessly with all the endless layers of friction.

To hobby is to demand instant gratification. The land of hobby seems to want to be connected to the land of research. But research is only truly useful when the desire for instant gratification can be dispelled.

If I'm reading the author correctly, computer modeling might be that magical land where hobby and research can commingle. Where instant gratification can produce tangible research results.

I'm not convinced. Is it really a matter of tooling? Because it seems to me that any kind of modeling that would actually have research potential is going to have to be invented. So now my hobby involves research and invention?

Maybe after I retire.

  • logram 5 years ago

    Hopefully I didn't misunderstand what you meant, but I'd argue that a hobby is exactly not instant gratification. That I would call entertainment.

    In my opinion the gratification of a hobby comes from enjoyment of the process itself. For example, if you play music, drilling through the same couple of measures until it sounds right might not pay off until the end, which might take hours and hours of work across many days. If you don't enjoy the process then you won't take it up as a hobby, but that doesn't mean there is constant gratification. Even more, the end result might not be as good as a professional product -- but it's yours and it's the journey that counts.

    I say that instant gratification is entertainment because I would compare that to playing games or watching a movie. There's no process there, it's just gratification.

    An example would be the people that make emulators as a hobby. Across their journey they find so many special cases and undocumented behaviour that it is certainly a lot of work riddled with unexpected obstacles. But exactly that is the process of problem solving and ultimately what they enjoy.

    • vinceguidry 5 years ago

      Music is a great example. I used to play guitar, I don't now because the time investment needed to get to fulfillment is too heavy. I can pick up a guitar and noodle around with it, but the impetus to take it seriously as a hobby is just no longer there, because of all the perceived friction.

      Of course, if I'd taken it seriously as a kid, I wouldn't have that friction and I could count the guitar among my regular hobbies. I don't have that same attitude towards the keyboard, which requires far less finger dexterity and thus practice. I'll probably never pick up a guitar for more than a few minutes ever again, but I can see myself buying a keyboard and stand and going at a piece of music for ten minutes or so every day. (it's a bit of a contrived example, the real reason I don't play my guitars at the moment is because I don't like what it does to my fingers.)

      This is what I mean by instant gratification. Everybody draws their line differently, but it's hard to argue that the line doesn't or shouldn't exist. A hobby is what you spend your excess time and money on without expecting a financial return from it. Having an impact is fine, but commerce it isn't, otherwise you call it a side project.

  • phkahler 5 years ago

    >> Maybe after I retire.

    Or before you began working. I think having kids model things is a great idea - they'll learn a lot that you just can't get from school. I agree that as a working adult there is a lot less time for such things, but rather than focus on instant gratification I've just narrowed the number of projects I work on to 1 immediate and 1 planned (which may start before the immediate one is done). Wanting to do anything else is just more reason to finish the thing currently underway.

CupOfJava 5 years ago

I want to model my home in 3D, with measurements. What's a good free alternative to autocad for that?

  • trentlott 5 years ago

    Blender allows for the use of human units. It also contains engines for physics and lots of videos explaining how to do interesting things, including allowing for Python scripting

    Choosing a very popular free platform has benefits (blender.org)

Quequau 5 years ago

Years ago I read "Growing Artificial Societies - Social Science from the Bottom Up" by Joshua M. Epstein and Robert L. Axtell and was really motivated to do computer modeling as some sort of hobby.

For me at least the problem was once I got their original model up and running I wasn't able to sustain the focus to construct a graphical representation that was compelling. So I never went back and debugged the stuff that I added to model (not seriously anyway).

  • Quequau 5 years ago

    lol and that comment just trigger an old google alert I have running on this topic.

TaylorAlexander 5 years ago

Well I definitely spend most of my hobby time modeling 3D printed robots!

meheleventyone 5 years ago

I think it has, just not in the way the author intends here. This article was basically written on the cusp of the game modding scene really taking off online, followed by the indie game revolution of the early 2000's into what we see today as a glut of games being released. The popular computer modeling pastime is game development and exhibits much of what is talked about in the article.

moron4hire 5 years ago

Definitely needs a "(1996)" on the title.

anonlastname 5 years ago

Many games have a modding community. A lot of these mods are usually suprisingly detailed model packs.

dkuebric 5 years ago

Seems like the author was right; I'd look to Minecraft as the analogue for model trains.

Joakal 5 years ago

For those that are developers/programmers, you might like OpenSCAD where models are generated from code. I prefer it over knowing where/when to use menu items.

As a bonus, the exports work with 3D printers.

Source: Printed parts of a hand as a hobby.

  • lkschubert8 5 years ago

    I absolutely love the idea of OpenSCAD, but it's speed is extremely painful, even for things that are geometric. As soon as you start trying to make something more organic it crawls.

aaron695 5 years ago

Like the Goat Simulator?

Seems like we are there?