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Simulating Societies
blamanj writes "Most of us were exposed fairly early to Conway's game of Life.
A few simple rules produce a fascinating variety of behavior. Now, it
appears that similar simulations can predict the behavior of populations and human societies."
This article is really describing modeling using multiagent systems. Though very simple multiagent systems may resemble cellular automata (such as Conway's Life), they are not the same thing. Though they have been described in very convenient graphical representations using grids in the article, agents can model more complex behavior and need not be determinisitic (i.e. they may have a random element).
Another way to look at it is that cellular automata like Life use a single deterministic rule to govern the whole system. Agent-based systems, on the other hand, model goal-oriented behavior of the individual objects.
Again, Conway's game can be viewed as a very special case of an simple agent system, but the spirit of what is being done with agent systems is typically more involved. Comparing these systems to Conway's game of Life may create an incorrect impression for those not familiar with agent programming.
Hmmm... So the simulation is accurate, but I would hypothesize that it does not show that a free society will trend towards "honesty."
Nonperiodic Central Trajectory
The problems lie elsewhere. Two that come to mind quickly are (1) lack of agreed upon factual data to use as the basis of the hypotheses. Do people with green skin have more or fewer babies out of wedlock than people with orange skin, and has this number increased or decreased over the last 10 years? Even in the US, with the Census data and tremendous amounts of market research, there are no agreed-upon answers to fundamental questions of data. Plenty of Newtons but no Kepler.
(2) None of these models are reversible. Put in a starting point of today's conditions, set the time increment to -1, and run the simulation backwards for 100 years. What comes out will be nothing like the world as it actually was in 1900. If we can't accuratly predict what happened in the past, how can we have any belief that the models tell us anything meaningful about the future?
sPh
But that's exactly what the corruption/honesty simulation is trying to argue against. It is saying that traditional social science modelling is fundamentally flawed because it assumes everyone in a particular group behaves the same and has unlimited knowledge.
A social model that viewed individuals as multiple copies of the same fully informed person could thus never "see" the social transformation that Hammond found, for the simple reason that without diversity and limited knowledge, the transformation never happens. Given that human beings are invariably diverse and that the knowledge at their disposal is invariably limited, it would seem to follow that even societies in which unsophisticated people obey rudimentary rules will produce surprises and discontinuities--events that cannot be foreseen either through intuition or through the more conventional sorts of social science.
The program that ended up as the most successful was also the simplest. University of Toronto Game Theorist Anatol Rappaport had submitted a program he called tit for tat. Tit for tat initially cooperated with all the other players. In subsequent turns if the other player it was interacting with had defected last turn, it defected this turn. If the other player had cooperated last turn it cooperated this turn.
Yes, the interactions between people are very complicated, and this game is very simple. Still food for thought though.
A model pictures reality by simplifying it. This research is emulation.... The problem is that everyone KNOWS the outcomes. The IMPORTANT question is whether the underlying assumptions catch the true causal forces.
And there are real problems with this school of thought, not the least of which is its claim that getting complex interactions out of simple assumptions is any harder than getting complex interactions out of a great deal of assumptions. It should be self-evident that complexity in this type of research stems largely from the number of actors, not the determinants of their behavior.
Deeper problems include assumptions of rationality and intentionality on the part of actors. There is also a tendency towards selection bias and selectivity THAT IS NEVER ADDRESSED. IE, this author may think he explains ethnic genocide in Rwanda, but never points out that his logic fails miserable in places like Switzerland, Brazil, Mexico, Russia and much of the Middle-East, where his model would predict much MORE conflict than we see.
Do you also support Disney's position that I should have to pay them a royalty every time I watch a DVD that I purchased? I won't buy DVDs or CDs or anything else under that plan, and I won't buy books under your plan. Period. If you want to kill your market, go right ahead -- there's pleanty of other entertainment sources that take a more reasonable view.
If all this should have a reason, we would be the last to know.