Douglas,
One major problem you are going to run into is the inability of non-chaotic
systems models to generate surprise (like innovations) as such models are
completely defined. Innovation is one of the major factors from the human
side and Mother Nature has tricks up her sleeve too. Any model which
cannot explain it endogenously is fatally flawed. Economists have never
been able to do it which is why they ignore it (they treat it as a residual
in the power function of the production function). So the conventional
algorithmic approach ultimately won't help, ditto non-chaotic simulation.
You need something like biologist Stuart Kauffmans bootstrap model which is
a chaotic simulation model, but it is only a baby step towards what you
will need. Even then you have no way of specifying new future technologies
which have the habit of completely transforming the global economic
structure. You would only have some metaphorical clues as to how the
transformations might occur. These makeovers occur every fifty to sixty
years, so you can't assume them away in any long term model.
In this I am agreeing with Ed and Eva, i.e. You have to have some theory
of how things work, and you have to be able to conceive of and simulate
alternative systems to the one we have now (entirely different social and
technical systems). Otherwise you are simply projecting the status quo,
which might be interesting in the short run, but is of no earthly use in
the long run when we want to be able to imagine things being different than
they are.
You might want to look at the work which has been done at the International
Institute for Advanced Systems Analysis in Laxenburg Austria. Cesar
Marchetti, who works there has done the only worthwhile work on
anticipating innovation and energy systems that I have seen.
Mike H
>This is a response to several people who have commented on my idea of
>running a simulation of the world economy, and I should mention
>especially Pete <[EMAIL PROTECTED]> who has some very useful ideas,
>(as Tom Walker has also pointed out).
>
>First a few general comments:
>
>I want to do this myself, but I am willing to accept help, and I am
>most interested in help collecting data. If I get enough help I am
>quite willing to surrender all claims to this project to the
>futurework mailing list as a whole and will gladly let someone else
>take over and run the project if the list as a whole has no serious
>objections at the time.
>
>I would like someone more reliable than me to keep an archive of
>whatever is produced, in case I get run over by a bus, and I'd prefer
>it to be made available by FTP to anyone who wants it.
>
>I'd like to use only public domain or freely redistributable math
>libraries so the whole project can be freely redistributed under the
>GNU public license.
>
>I think the target language should be plain-vanilla ANSI C with as few
>preprocessor directives as possible, and it should compile with the
>GNU gcc compiler (djgpp on DOS or Windows systems) using -Wall to
>enable all warnings -- but without any warnings produced. Having just
>said that, I will probably do some rapid-prototyping using Pascal
>which is easier and supports array bounds checking, then translate it
>into C using the p2c translator at some point. I'd like to use a real
>programming language, a good one, but unforunately none has ever been
>written! (Though I could say a few nice things about ML or Python,
>which most people have never heard of.)
>
>In an earlier message (which I regret not responding to), Pete wrote:
>
>> On the other issue, I have no fear of mathematics, nor engineering,
>> in analysis of social issues. However, I will state categorically
>> that algorithm-based analysis is inadequate to the task, and most
>> likely actively deceptive. Nothing less than fullblown simulation
>> is able to yield a valid analysis, but this is something easily within
>> reach of current computing power. Systems engineering applied to
>> the whole problem of economic srtucture is fully mature and powerful
>> enough to handle the problem, and is long overdue to supplant the
>> voodoo algorithms of orthodox economic theory.
>
>I might have been more likely to respond to this comment if I
>disagreed with it, such being human nature, but since it is so
>obviously correct I just let it pass by unnoted -- sorry Pete.
>
>In particular I agree with his endorsement of systems engineering, and
>since I do, I think the first step must be requirements analysis,
>followed by design, and only then can code be written -- except for a
>small amount of rapid-prototyping as proof of concept.
>
>Commenting on my plans to do a simulation Pete wrote:
>
>> This is an approach I have advocated for a long time, so of course
>> I'm all in favour. However there are some important points to make:
>> a proper simulation is not a trivial project; I had envisioned it
>> being the product of a team effort in the order of several man-years.
>
>I'm still working on requirements analysis, but I have a few
>preliminary design ideas in mind. I'd like to make it entirely
>database driven, for several reasons, not least of which is my
>agreement with Pete that this should really be a big project.
>
>As I see it, the programs which actually run the simulation are in
>some ways the least important part of it, and should take the least
>work. The hard part is collecting good data and making it available
>in some standard form. I envision the collection of data being
>expandable almost endlessly, so that the simulation that might be up
>and running in a few months could be expanded with several man-years
>more work by simply collecting more data.
>
>To carry on with Pete's comments:
>
>> Most importantly, the simulation will be of no value if it is
>> algorithm-driven. To reflect the true picture, it must be an FSA
>> (Finite State Automata) model. Algorithms may be deduced from its
>> results, but not ordained in its construction. ...
>
>I more or less agree with this, though might have some quibbles with
>using a finite-state machine, which does have some limitations. I am
>quite in sympathy with Pete's views on algorithms, but I think the key
>word is "ordained" -- there will be some room for algorithms loaded
>dynamically as data for the purpose of approximating what is not
>known. A model is just a model, after all, and cannot hope to do more
>than estimate most things, but I do want to minimize any reliance on
>"canonical" algorithms, to extend Pete's metaphor.
>
>> ... The simulation should model the actions of individual players,
>> and be iterated over cohorts over time. ...
>
>I'd like to turn that around and say that the simulation will model
>arbitrarily small units, which could eventually be individuals, but to
>start out with the units will probably be quite large, such as
>"third-world teenagers" or "literate women of childbearing age".
>Exactly what units are used will be defined in the database.
>
>> ... A well constructed simulation should be able to model
>> any form of economy one can imagine, and not be limited by the
>> constrictive assumptions built into an algorithm-driven simulation.
>
>Of course. No doubt about that.
>
>> By the way, algorithm-based simulations already exist, and are used
>> regularly by economists, which should be a clear demonstration that
>> they are no damn good. To see an example, check out the International
>> Futures model which I believe can still be found at IFS.org.
>
>I'd like to make it possible to run equivalent models, so we can take
>apart the existing ones and see just why they are no damn good.
>
>As I see it now, the database should include a number of named
>simulations, each one of which could be loaded and run, modified and
>saved under a new name, and printed out with graphs of results.
>
>I would also like to try defining an algebra or space of models (both,
>really, I think both algebraic and topological structure needs to be
>represented), so that one could do various algebraic operations on
>models -- combining two somewhat inadequate models that are
>significantly different into a single model that is better than either
>of them.
>
>I hope this all sounds plausible to you, Pete. I need to formalize
>this into a requirements document -- or the first draft of one, and as
>soon as I get some of that written I will post it here.
>
>Mark Measday also has some interesting comments which should be
>reflected in formal requirements:
>
>> Naively, should the simulation work well and teach lessons in management
>> of the world economy to those looking for that data, how will the
>> simulation recursively model itself within it own simulation? It must be
>> an unknown quantity, no? As the results of its model produce unknown
>> outputs which cannot be input to the model before it is run?
>
>I would definitely like to model all real world processes to some
>extent, and much as it may seem like ivory-tower poppycock, various
>political and economic view are part of the real world -- they
>influence decision makers and can be reflected in interest rates and
>other factors.
>
>I think we should incorporate a number of data records reflecting
>political and economic views. The influence of a particular viewpoint
>is questionable and will have to be guessed at, to start with, and
>some models will simply have zeroes to indicate no influence
>whatsoever. To choose an example at random, we might have a "Jay"
>entry whose fields represent the influence of Jay Hanson's views on
>the world economy as a whole. You are at liberty to provide your own
>estimates as to the values of those fields!
>
>And so, for completeness we ought to incorporate Mark Measday's
>suggestion and include an entry for the effect of this simulation on
>the world's economy as a whole. You are also at liberty to provide
>your own estimates as to the values of the fields in that entry. I
>like to think that more of the world's decision makers would trust the
>results of our simulations than would trust the speculations of a Jay
>Hanson, but then again, many of those people are politicians, not a
>group known for their enlightenment.
>
>It may seem that the simulation would have difficulty capturing its
>own effects, but this is simply a matter of recursion (or iteration),
>and not really a problem. One version of the simulation could be run
>with the fields representing its own effects on the world economy set
>to zero -- most certainly the right initial conditions. Another
>version may have some higher values in those fields, and a more
>sophisticated version may have second and higher order effects
>represented so that the effects start out at zero and change with
>time.
>
>I wouldn't be doing this at all if I thought the simulations would
>have no effect on anybody, ever. I like to think we could do it well
>enough that people will take notice, at which point it may have some
>small effect on decision makers. But who knows? It's worth a try,
>and I want to try it. If anyone wants to help, please do!
>
>I should mention that Jay posted a quite well written reply to my
>earlier remarks on this simulation project, including a number of
>numbers. I like numbers, myself, though I always view them with some
>suspicion, particularly when they don't come with an error estimate.
>If someone talks about 200 million people I always suspect they mean
>plus or minus 100 million unless explicitly told otherwise. I'll make
>a note of Jay's numbers and try to use them where appropriate. I'll
>entertain suggestions about just what that appropriate use might be.
>
>Regardless of anything said here or in my previous messages, I have
>no personal animosity against Jay, and quite enjoy reading his
>comments. He notes that "debating" on the internet is his idea of
>fun, and who am I criticize that, though I think the word
>"pontificating" might be more appropriate.
>
> dpw
>
>Douglas P. Wilson [EMAIL PROTECTED]
>http://www.island.net/~dpwilson/index.html
