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Scientists Discover Tipping Point for the Spread of Ideas
An anonymous reader writes "Scientists at Rensselaer Polytechnic Institute have found that when just 10 percent of the population holds an unshakable belief, their belief will always be adopted by the majority of the society. 'When the number of committed opinion holders is below 10 percent, there is no visible progress in the spread of ideas. It would literally take the amount of time comparable to the age of the universe for this size group to reach the majority,' said SCNARC Director Boleslaw Szymanski. 'Once that number grows above 10 percent, the idea spreads like flame.' The findings were published in the July 22, 2011, early online edition of the journal Physical Review E."
This is bullshit and I will never believe it.
Probably has something to do with lack of sex with women.
No, the article is specifically speaking about sentient beings, not parasitic worms.
http://arxiv.org/abs/1102.3931
seems a lot more reasonable than the article/summary:
We show how the prevailing majority opinion in a population can be rapidly reversed by a small fraction p of randomly distributed committed agents who consistently proselytize the opposing opinion and are immune to influence. Specifically, we show that when the committed fraction grows beyond a critical value pcâ10%, there is a dramatic decrease in the time Tc taken for the entire population to adopt the committed opinion. In particular, for complete graphs we show that when ppc, Tc~lnN. We conclude with simulation results for ErdÅ's-Rényi random graphs and scale-free networks which show qualitatively similar behavior.
The authors (on a quick read of the original paper) are talking about a saddle point in the adoption of a new idea. This is basically the same as epidemiology, and their paper can be viewed as about a model of contagion in the case of infectious agents who can't be cured and don't die. So, in that sense this is like the classic result in epidemiology that an epidemic can't spread if the "basic reproduction number" is less than 50%. It's not magic, and it doesn't mean that if you get 10% + 1 acceptance is guaranteed, just where the tipping point is in this "modified epidemiology."
I guess they mean that of those idea that catch on, the point was at 10%. More than 10% Americans "believe" in evolution, but I don't see it spreading like wildfire.
But it did, originally. Only now there's 10% believing in Intelligent Design, so you're screwed.
The idea may only need to be held by a small segment of the population; for example, the scientists in a specialised sub-discipline(~hundred or so people), the major media commentariat in a particular country of locality(~few hundred people), the academics in a wider field, e.g. economics (~few thousand people), or perhaps the opinions in a small sized nation.
I give you a good example: In Ireland (pop. ~4 million), the entire country went on a mad house buying binge, with the skeptics being ridiculed, ignored, or told by the nation's premier to go and commit suicide. Here's a retrospective blog post on the brazen insanity of those days. You'd kind of have to be from Ireland to get it all, but I think the Shamrock Island video explains itself.
Now, if you added up the people during the Celtic Tiger Boom who worked in the financial, construction, and property sectors, you'd pretty comfortably reach 400,000 people; ~10% of the population. And I can assure you that most of these people were indeed true believers in the idea that property prices would continue to grow forever. For any that weren't, the slack was picked up by overpaid public sector workers with property fetishes and the usual talking heads in the media. Ireland is a small country, so it was relatively easy to reach a 10% level in many sectors.
I stress that the eternal house price boom was a deeply held and virtually unassailable belief during the Celtic Tiger years. Skeptics were laughed at and ridiculed publically. Here's a quote from the article:
This was a few months after the country's major bank, Bank of Ireland, introduced 100%+ mortgages for buyers, which revved prices upwards again after the beginning of a brief slowdown.
This post is getting a little parochial, but to bring this back to the topic, I remind everyone that Ireland is now a bankrupted state in IMF hands, devastated by a massive property bust and credit crunch, with 5 out of 6 banks nationalised. This instance of "true believers" tipping over public opinion lead to the ruination of an entire country. I think its a good example of how the spread of ideas and ideologies can be damaging to societies, and why it's so important to challenge this spread in the early stages, because believe me, it's impossible to reverse things once the wildfire takes hold of the wider population.
May the Maths Be with you!
So either this guy is Hari Seldon and has a working theory of psychohistory, or this is mostly bullshit.
I don't see why the % would change just because I read their bullshit paper. I like 10%, so I'll leave the state unchanged by not reading it.
You split populations into smaller subsets. Let's say you're the only person with an idea. You need to work with a population of 10 or fewer to be able to spread that idea. Anything larger than 10 will fail. So you converted the initial 10. You can now spread the idea through a population group of about 100, then 1,000, then 10,000, then 100,000, then 1,000,000 and so on.
So if your group of 300 has a radical idea and you're slinging it out everywhere you can, you're probably going to fail dismally since you're targeting too large of a population.
"Lack of speed can be overcome. In the worst case by patience." --Znork
In short, the paper repeats analysis and numerical simulations of a simplified 'agreement model'. People are abstracted as nodes on a graph, communication happens between them, and consensus is reached. If a graph is initialized randomly, with nodes 'believing' either A or B, eventually (in log(N) time) the graph reaches consensus with every node 'believing' A xor B.
This paper adds a twist; some fraction of nodes are 'committed' to A, and cannot ever be convinced of B. To quote the paper:
Now, if even one node cannot be convinced of B, then no consensus can be reached -- but it doesn't really matter. If the fraction is really small, then you can more or less ignore them.
The interesting part about that paper is their threshold effect -- once p gets to be over 10%, not only does A eventually win, but it does so -quickly-.
The applications to politics still hold, but not on the big, obvious issues. Those issues, like taxes and abortion and health care and anything else that really makes the news, have committed believers on both sides -- they're outside the scope of study. Where this research becomes really interesting is in quieter, uncontroversial issues -- like regulation details, or climage change before Al Gore. There, this research suggests that the influence of sockpuppetry and lobbying is nonlinear -- beyond a critical point, the lobbyists completely win.
Of course, caveats about "the real world isn't an abstract graph" apply.
"Evil company X is threatening to restrict our rights! Let's all get together to stop--OOOH! SHINEY!!!" -- AC