Crowds

Clustering and the Ignorance of Crowds

Over on the Cheap Talk blog (@CheapTalkBlog), Jeff Ely (@jeffely) has an interesting post about the "Ignorance of Crowds." The basic idea is that when there are lots of connections among people, each individual has less incentive to seek out costly information — e.g. subscribe to the newspaper — on their own, because instead they can just get that information ("free ride") from others. More connections means more free riding and fewer informed individuals.

I take a much more complicated route to the same conclusion in "Network Games with Local Correlation and Clustering." Besides being sufficiently mathematically intractable to, hopefully, be published, the paper does show a few other things too. In particular, I look at how network clustering affects "public goods provision," which is the fancy term for what Jeff Ely calls subscribing to the newspaper. Lots of real social networks are highly clustered. This means that if I'm friends with Jack and Jill, there is a good chance that Jack and Jill are friends with each other. What I find in the paper is that clustering increases public goods provision. In other words, when people are members of tight knit communities, more people should subscribe to the newspaper (and volunteer, and pick up trash, and ...)

It's pretty clear that the Internet, social media etc... are increasing the number of contacts that we have, but an interesting question that I haven't seen any research on is How are these technologies affecting clustering (if at all)?

Social Dynamics of the Bin Laden Death Celebration

Many people, including myself, have been a little disturbed by the wild celebrations of Osama bin Laden’s death.  An article in the New York Times quotes a number of psychologists that explain the partying as natural cathartic “pure existential release.”  It’s not until the last two paragraphs of the article that they hit on what I think was the real driving force behind the “chanting and frat-party revelry”: crowd dynamics.  The article says, “in a crowd of like-minded people, the most intense drives for justice become the norm: People who may have felt a mix of emotions in response to the news can be swept up in the general revelry.”

The dynamic is similar to that detailed by Cass Sunstein in his book Going to Extremes (I’m currently writing a paper that develops formal models to explain the going to extremes dynamic)Sunstein describes a pile of social psychology research demonstrating that when like minded individuals discuss their opinions, they become more extreme, rather than converging to the mean.  A prime example is risk taking among teenagers, a bunch of kids that would never try driving their car 150 miles an hour or shotgunning cases of beer on their own, will turn into drunken race car drivers in a crowd of their peers.  I imagine the dynamic was much the same around the Georgetown bars last Sunday night.  Riots can erupt the same way.  Most people wouldn’t think of throwing bricks threw store windows or setting cop cars on fire, but in the midst of a rioting crowd our behavior can be much different.