To affinity and beyond! How our preference to be among similar people interacts with our social ecology

Race isn’t the only factor by which neighborhoods can become segregated based on people’s decisions to relocate to live near similar others. For instance, some investigations have proposed that residential mobility may be increasing the political polarization of the United States, as individuals tend to move to places which match their political ideologies. In his book The Big Sort, Bill Bishop (2009) argues that ideologically-based migration is leading to a more polarized society. More recently, Motyl and colleagues (2014) showed that people whose ideologies did not fit with community were more likely to want to relocate to a new neighborhood. The same thing appears to happen with wealth, as wealthy couples tend to relocate to expensive metropolitan areas, inadvertently leading to rural areas becoming poorer (Costa & Kahn, 1999). These investigations suggest that greater residential mobility, combined housing choice (choices in where one relocates to), can translate into higher levels of homogeneity within neighborhoods in wide number of domains.


Fig 1. The progression of residential segregation over time, in the Schelling model of residential segregation. You can try experimenting with a demonstration of Schelling’s simulation yourself. (Requires Wolfram cdf player plugin)

Overall, our preference to form relationships and live alongside similar others can interact with our social environment in a number of ways. The amount of opportunities we have to form new relationships or move from residence to residence can translate into higher levels of similarity among friends and romantic partners in society, and our choices based on preferences for similarity can, on an aggregate level, end up creating a fragmented and stratified society. This might be an important thing to think about when you decide whom you associate with in the future. While it would certainly be unacceptable (at least in modern, Western societies) to dictate who can marry whom, who can befriend whom, or what neighborhood certain types of people should or should not be able to move to, understanding that our choices have implications for the nature of society at large is very important. Like the agents in Schelling’s simulations, we are all embedded in a complex system where the tides flow in both directions: our environment can affect and constrain our choices in friendships, and in turn we can affect our environment with our relationship choices themselves. Something to think about the next time you consider making a new friend or moving to a new neighborhood!


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