Social mobility has notoriously slowed in recent decades. While there have been various attempts to understand why this is, new research from Harvard takes us down an interesting path. It suggests that the wealth of our friends play a role in our wealth as adults.

The researchers analyzed around 21 billion Facebook friendships, and found that children from poorer homes were more likely to earn more as adults if they grew up in areas where the chances of friendships with wealthier children were more likely.

Rich friends

The researchers examined data from around 72 million Facebook users from the US who were all aged between 25 and 44. The friendships on the site were used as a proxy for friendships in the real world. They then used an algorithm to rank users according to their age, location, socio-economic status, and so on.

They then measured how often richer and poorer people engaged with one another to try and gauge the share of people’s friends who were either above or below the average socio-economic level. Last, but not least, the researchers compared this metric with previous research into social mobility in the US.

The results were extremely similar, with the levels of “economic connectedness” one of the strongest predictors of future social and economic mobility.

Why this is

A second paper from the team then aims to explore why this might be. The results suggest two key factors underpin this phenomenon. The first revolved around the exposure between poorer and wealthier children and includes things such as whether they attended the same school.

Of course, even if poorer children attend the same school as their wealthier peers, there’s no guarantee that they’ll hang out. Nonetheless, the researchers found that around half of social disconnection between the two groups was a result of a lack of exposure. The remaining half, however, was due to the difficulties involved in getting groups to mix even when they are exposed to one another.

The results highlight that attempts to improve social mobility via schools and regions were valuable but aren’t enough on their own. Where richer and poorer children meet was also crucially important on whether they become friends. For instance, friendships forged in churches were highly likely to cross class lines.

The researchers hope to extend their work into other countries to see if the same phenomenon exists there too, and believe that their findings provide invaluable insights into the importance of social capital in tackling social mobility.