Towards a Simulation of the World Economy
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Towards a Simulation of the World Economy |
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I'd like to write a program to run a simulation of the world economy, to see if any of the arguments from people like Jay Hanson follow from their own data, and then I'd like to do a sensitivity analysis to see what are the most important variables.
I propose to put this program up on the web in source code form as well as compiled binaries, so that everyone can check to see how plausible the model is, and can play with it a bit.
I do have some expertise in this area, having worked on a simulation of part of the Canadian air traffic control system in Ottawa a while back, but by putting actual source code up on the web I hope to minimize the dependence of the model on my own personal expertise.
To do this, I will need some data, and I hope Jay Hanson and others will be willing to provide the data underlying his own conclusions.
I see this as a worthwhile project, consistent with my often stated preference for algorithms over arguments, and it is also a good example of social technology in action.
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 some interested group of people such as the members of the futurework mailing list, and will gladly let someone else take over and run the project if the other people involved have 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.
This is not a project that I'd undertake for my personal amusement. I like to think we can do this well enough that some people will have 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'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 it important to have a good simulation that is freely available to anyone who wants it, with full source code and all available data.
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 unfortunately none has ever been written!
(Though I could say a few nice things about ML or Python, which most people have never heard of.)
I believe in the methodology of systems engineering, and so I think the first step in this project 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. I think this methodology is important because it helps catch mistakes early on, and because mistakes caught early are much easier and cheaper to fix.
I'm still working on the 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 feeling that this should really be a big project and will need to grow a lot once implemented.
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.
It is my intention 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.
I'd like to make it possible to run simulations that are equivalent some well-known models, so we can take apart the existing ones and see just where and why they don't work.
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 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 views are part of the real world -- they influence decision makers and can be reflected in interest rates and other factors.
We should therefore 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 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 any single person, 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.
There are sources of unpredictable values that will cause problems for any simulation. We can not yet predict the weather more than a few days in advance, and yet weather can have dramatic effects on the world economy. Political changes are also hard to predict, and so are the results of human innovation.
But the usual way to handle values that cannot be predicted is to use random number generation to supply such data and then rerun the model many times, and I think that should work OK. The basic idea is to use what are sometimes called Monte Carlo methods to deal with anything that cannot be accurately modelled because of unpredictables like the weather, and to therefore discover the common features that are independent of the unpredictables by re-running the model with different random numbers, and averaging the results.
I've now done some tentative impure requirements analysis for a simulation of the world economy. I say impure because I can't get design ideas out of my head. It is probably best to admit this up front and also to hint broadly at what these design ideas are.
Currently I envision this project as implemented by a relatively simple program and a much more elaborate database containing a lot of carefully selected data. By 'database' I mean a collection of named files, probably bound together by a common base name and distinguished by distinctive extensions.
The system that I envision is something like a spreadsheet that loops through a series of records making changes by applying certain rules which are also stored in these records, and indeed could be implemented as a spreadsheet, though I probably won't implement it as one. If you are in doubt about what I have in mind, try thinking of this as a spreadsheet and you probably won't be too far wrong.
Indeed, use of a spreadsheet for rapid-prototyping may be wise. People comfortable with spreadsheets may want to play around with this a bit, to see what is possible.
Some people who use spreadsheets for ordinary business applications may be unused to the idea of using a spreadsheet as a programming language for writing programs that can simply go on and run by themselves.
Usually people set up something on a spreadsheet and then change various numbers to see what will happen -- the result being a change from one static state based on the old numbers to another static state based on the new ones. That is, of course, their most common use.
But it is quite possible to use a spreadsheet as a programming languages for dynamical programs that have a continuous loop, which runs until interrupted (or until a stable equilibrium state is reached).
When working this way, a spreadsheet loops though all fields (columns) of all records (rows) and does whatever updates are necessary as they are encountered, but no more than once per loop. That is not behaviour that a large scale economic model should use, because it would involve updating some records too often.
What I have in mind could be thought of as a spreadsheet in which each record has a first field which is countdown timer, changed once per iteration, and all other data fields in the record have an implicit "and timer=0" condition, so they are only updated when the timer counts down to zero -- the timer itself resetting by coping its initial value from another field the iteration after it reaches zero.
As I envision it, the program loops though a series of records in a database, reading and updating them according to "instructions" also contained in that database. By 'instructions' I don't mean computer programs but just important data values and limits, or symbolic expressions, such as could be represented in any cell of a spreadsheet.
As I see it, a few of these instruction are hardly ever changed, and in fact cannot be changed without going through several steps of supplying appropriate passwords. Included in this list of special instructions are flags or values stating which instructions fall into this class, and which may be more easily modified. Some other instructions are (therefore) more easily modified but can only be changed by the operator, and a few more instructions can be modified by a running program.
Broadly speaking I think there will be two main classes of records:
Below I have a list of preliminary requirements, and after some of them a design or implementation hint based on this quasi-spreadsheet model. After a few of these requirement statements I include a design note in parentheses.
(Symbolic expressions in cells of the (quasi-)spreadsheet would be considered data, and could be modified, but in general would be modified rarely and not normally by the operations of the program.)
(A record or spreadsheet row could represent a large geographic region, and in simple models the whole earth, or could represent a much smaller region like a village. It could represent a large group of people, like all males, or all young males, or young males of an ethnic group, or ultimately a single person.)
(How long a length of time is represented by the values in one row of the quasi-spreadsheet would be encoded in the initial values for the countdown timer, and would be updated from all other relevant records each time the counter reached zero.)
(Region or person granularity would depend only on how many rows and how much space or number of persons each row represents. Time granularity is represented by the initial values placed in the countdown timers and can be changed by changing the values in the (semi-constant) fields used to reinitialize the timers.)
(It should be possible to include in some "cells" of the "spreadsheet" a URL representing a file to obtained by FTP, or a procedure to be run by remote procedure call.)
(Space or person-count granularity could be changed by splitting rows -- duplicating them then making necessary changes to reduce region size or person counts in each new row.)
(It should be possible to perform a single operation to make large changes in time-scale over a wide set of rows by simultaneously changing from daily update to weekly update, or annual update to monthly. Similarly it should be possible to make large scale changes in regional or cohort data by splitting country records into province records or province records into township records -- etc.)
This is only a first draft, incomplete and very crude in places, but it should suggest the general idea. I'd like anyone interested in this simulation project to look it over and make comments, preferably to the mailing list as a whole -- so that it will stimulate more discussion, or to me personally if you prefer. I will try to save all comments so that at some point they can be archived together.
The requirements given above are just rough drafts, and already have probably proven just how rough they are by confusing people.
Essentially, they boil down to this: I don't want to write some oversimplification, I want to write something that can be used for state-of-the-art models -- something without built-in limitations, that can be incrementally improved by adding better data. And I'd like to let them incorporate better data automatically by obtaining it from remote sites, so that the resulting simulation can be very large and powerful without requiring any of us to be experts.
This should make it possible for a simulation based on this software to be a distributed simulation, making use of results obtained over the net. If someone was to use this software (or some other) to create a good simulation of the Canadian, U.S., or British economy, rather than doing it over again or manually downloading data from that other simulation, it should be possible for the simulator running the whole-world simulation to acquire or update it over the net on a regular basis.
Some people have expressed concern that simulations could help some people make a lot of money. Obviously a good simulation could be used by people to make money, by suggesting advantages transactions, but this was one reason that I wrote about coding the simulator in the most widely available programming language and making it freely available under the GNU public license.
I want a good simulation widely used for the public good, and I suspect that other good models that have been kept for the personal gain of the few have been a destabilizing influence behind some that massive flow of cash around the planet -- currency speculation, and related ways of profiting from good guesses.
I want to produce a good enough simulation that it will be widely used, and I want to make it freely available in source code format so that it will not only be used but will be maintained and improved.
The really good free open-source software products like Linux, GNU Emacs, and the GNU gcc compiler are much, much better than they would be if they were only the product of one person (or even one development team) -- they are the result of large numbers of people cooperating to collectively produce something useful to all of them.
So, that's the project. My thanks to all those people on the futurework mailing list who have joined in the discussion and contributed ideas to this nascent project, and I look forward to more.
Please give me your comments!
Copyright © 2009 Douglas Pardoe Wilson
Other relevant content:
New: Social Technology through Diagrams
New: Social Techs novel online
The main Social Technology page.
Find Compatibles, the key page, with the real solution to all other problems explained
Technological Fantasies , a page about future technology
Social Tech a page about Social Technology, technology for social purposes. I think I was the first person to use this phrase on the Internet, quite a long time ago.
Roughly corresponding to these web pages are the following blogs:
Social Technology the main blog, hosted on this site, with posts imported from the following blogger.com blogs, which still exist and are useable.
Find Compatibles devoted to matching people with friends, lovers, jobs, places to live and so on, but doing so in ways that will actually work, using good math, good algorithms, good analysis.
Technological Fantasies devoted to future stuff, new ideas, things that might be invented or might happen, such as what is listed above and below.
Sex-Politics-Religion is a blog about these important topics, which I have been told should never be mentioned in polite conversation. Alright that advice does seem a bit dated, but many people are still told not to bring up these subjects around the dinner table.
I believe I was the first person on the Internet to use the phrase Social Technology -- years before the Web existed.
Those were the good old days, when the number of people using the net exceeed the amount of content on it, so that it was easy to start a discussion about such an upopular topic. Now things are different. There are so many web pages that the chances of anyone finding this page are low, even with good search engines like Google. Oh, well.
By Social Technology I mean the technology for organizing and maintaining human society. The example I had most firmly in mind is the subject of Find Compatibles, what I consider to be the key page, the one with the real solution to all other problems explained.
As I explained on my early mailing lists and later webpages, I find that social technology has hardly improved at all over the years. We still use representative democracy, exactly the same as it was used in the 18th century. By contrast, horse and buggy transporation has been replaced by automobiles and airplanes, enormous changes.
In the picture below you will see some 18th century technology, such as the ox-plow in the middle of the picture. How things have changed since then in agricultural technology. But we still use chance encounters, engagements and marriages to organize our home life and the raising of children.
I claim that great advances in social technology are not only possible but inevitable. I have written three novels about this, one preposterously long, 5000 pages, another merely very very long, 1500 pages. The third is short enough at 340 pages to be published some day. Maybe. The topic is still not interesting to most people. I will excerpt small parts of these novels on the web sometime, maybe even post the raw text for the larger two.
This site includes many pages dating from 1997 to 2008 which are quite out of date. They are included here partly to show the development of these ideas and partly to cover things the newer pages do not. There will be broken links where these pages referenced external sites. I've tried to fix up or maiintain all internal links, but some will probably have been missed. One may wish to look at an earlier version of this page, rather longer, and at an overview of most parts of what can be called a bigger project.
Type in this address to e-mail me. The image is interesting. See Status of Social Technology
Copyright © 2007, 2008, 2009, Douglas Pardoe Wilson
I have used a series of e-mail address over the years, each of which eventually became out of date because of a change of Internet services or became almost useless because of spam. Eventually I stuck with a Yahoo address, but my inbox still fills up with spam and their spam filter still removes messages I wanted to see. So I have switched to a new e-mail service. Web spiders should not be able to find it, since it is hidden in a jpeg picture. I have also made it difficult to reach me. The picture is not a clickable link. To send me e-mail you must want to do so badly enough to type this address in. That is a nuisance, for which I do apologize, but I just don't want a lot of mail from people who do not care about what I have to say.