Feb. 18 (UPI) -- Urban planning has a direct influence on the cohesion of social networks, and in effect, the socioeconomic equality among a city's residents.
According to a new study, urban planning that fragments, rather than preserves, social networks tends to encourage increases in economic inequality.
Authors of the new paper, published Thursday in the journal Nature Communications, suggest urban planning policies should aim to keep valuable social networks intact.
Social networks -- the web of social relations that link communities members together -- help people gain access to resources, information, job opportunities and other forms of support.
"We know how important social networks are for our social and economic outcomes," study co-author Johannes Wachs, researcher at Complexity Science Hub Vienna, a research institution in Austria, said in a news release.
For the new study, researchers analyzed real-world data on social networks and inequality in dozens of cities. Their analysis revealed strong connections between social network fragmentation and inequality.
Scientists hypothesized that social fragmentation is driven by geography. To test their hypothesis, researchers analyzed data from a pre-Facebook social network called iWiW, which at its peak was adopted by nearly 40 percent of people in Hungary.
Researchers looked at how physical barriers influenced the connections between people in more than 500 town in Hungary.
"Urban sociology research says that people cannot easily build social ties when they are separated by large physical obstacles such as rivers, railways, highways or walls," Wachs said. "It was impressive to see this confirmed in our data: we could see evidence of strong physical boundaries in a city just by looking at its social network."
The analytical models deployed by Wachs and company revealed a strong link between physical, or geographic, fragmentation and social fragmentation.
The link between social disconnection and economic inequality is mediated by geographic fragmentation, researchers confirmed.
"If valuable ideas and information cannot float freely through a city because that city is physically fragmented, which in turn causes social fragmentation, we will see inequality," Wachs said. "We clearly see how strongly geography and income inequality are related."
Researchers acknowledged that social homogenization happens with or without physical barriers. That is, humans tend to befriend those who are similar, and friends of friends are more likely to become friends themselves.
But even when accounting for these inherent social tendencies, researchers showed physical fragmentation has a strong influence on the formation and shape of social networks.
The findings suggests physical fragmentation works to reinforce the human tendency to homogenize, leading sorting and segregation along race and class lines.
Study authors suggest urban planning decisions can influence the extent to which groups interact and mix.
"If these decisions reflect on our findings, we predict that cities will have fewer problems with inequality in the future," Wachs said.
Previous studies have shown that neighborhoods and cities with greater socioeconomic diversity tend to host greater levels of economic mobility.
Conversely, suburban sprawl, which can enable greater homogenization, has been shown to limit economic mobility.