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Friendship 246What do friends have to do with economic mobility? 

From an article by Behavioural Scientist

How does social capital relate to economic mobility? Social capital - the strength of an individual’s social network and community - has been identified as a potential determinant of outcomes ranging from education to health. However, efforts to understand what types of social capital matter for these outcomes have been hindered by a lack of social network data. In a two-part study recently published in Nature, Raj Chetty and his team analysed data from over 70 million Facebook users to find out.

They measured and analysed three types of social capital by location:

  1. Connectedness between different types of people, such as those with low versus high socioeconomic status (SES);
  2. Social cohesion, such as the extent of cliques in friendship networks;
  3. Civic engagement, such as rates of volunteering.

Their work revealed the importance of friendships across socioeconomic class lines. The share of high-SES friends among individuals with low SES - which they term 'economic connectedness' - is among the strongest predictors of upward income mobility identified to date. Other social capital measures are not strongly associated with economic mobility.

Differences in economic connectedness can explain well-known relationships between upward income mobility and racial segregation, poverty rates, and inequality.

In their second paper, the authors focus on the potential policy implications of this newly uncovered connection between friendships and economic mobility. If policymakers can successfully foster economic connectedness, the authors argue, they might be able to boost mobility too: “If children with low-SES parents were to grow up in locations with economic connectedness comparable to the average child with high-SES parents, their incomes in adulthood would increase by 20% on average.”

The authors provide clear but nuanced advice:

  • In places where people already tend to form cross-class friendships, increased exposure (via more integrated schools, neighbourhoods, and religious organizations) might help boost economic connectedness.
  • In places where people predominantly befriend those within their own group, extra steps may be necessary to foster these connections, such as restructuring local institutions and community spaces.

The extent to which individuals interact across class lines depends on both exposure (the socioeconomic composition of the groups to which people belong) and friending bias (the rate at which cross-SES friendships are formed conditional on exposure).

To date, there have been extensive policy efforts in countries on the exposure dimension, such as busing programs aimed at integrating schools; zoning and affordable housing policies aimed at integrating neighbourhoods; and college admissions reforms to boost diversity on campuses. Such interventions to increase integration can increase cross-SES interaction substantially. However, even if all such groups were perfectly integrated by socioeconomic status, half of the social disconnection between people with low and high socioeconomic status would persist because of friending bias within groups.

The analysis suggests that friending bias, like exposure, is shaped by social structures and institutions and can therefore be influenced by policy changes. Here are some examples:
  • Changes in group size and tracking in schools. In an attempt to overcome within-school segregation and to reduce the associated friending bias, in 2018, a school began assigning students to small, intentionally diverse ‘houses’ or ‘hives’ at 14. Such attention to the way in which students are tracked to different classes within schools and the size of the groups in which they participate outside class may be helpful in reducing friending bias more broadly.
  • Restructuring of space and urban planning. Administrators and students at a secondary school identified the architecture of the building as an impediment to cross-SES interaction. Duplicated rooms led to unintentional student segregation. The school recently attempted to reduce this source of friending bias through a construction project that created more spaces for all students to interact. Architecture and urban planning could have a role in reducing friending bias outside schools as well.
  • New domains for interaction. Another approach to reducing friending bias could be to create new programs and venues for cross-SES interaction. For example, a gym began a program to increase cross-SES connections by recruiting personal trainers from lower-SES backgrounds to coach their more affluent clients. This flips power dynamics, bridges social capital, and creates a genuine form of inclusion that disrupts the system of segregation, isolation, and racism that leads to the streets. The people in the program gain access to new networks and opportunities, while clients gain new insights and perspectives into complex social challenges. More generally, creating new programs and venues for cross-SES interaction (for example, through peer mentoring programs or internship programs) could help to reduce friending bias.

Part 1 of the study in Nature is here.

Part 2 of the study in Nature is here.

See also the article: What happened when France sent children from low-income areas to wealthy area schools?

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From an article by Behavioural Scientist, 08/11/2022

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