The Surprising Power of Weak Ties: Why Small Conversations With Acquaintances Make Better Days

By Noam Shemla · The Studies

TL;DR Psychology has mostly studied how close relationships affect well-being. Sandstrom and Dunn asked about everyone else: the classmates, neighbours, baristas and colleagues we only half know. Across three studies, people felt happier and more that they belonged on days when they had more of these small interactions than usual. The effect held when all interactions, close and casual, were counted together.

• Paper: Sandstrom, G. M., & Dunn, E. W. (2014). Social interactions and well-being: the surprising power of weak ties. Personality and Social Psychology Bulletin, 40(7), 910–922.
• Study 1: University students reported, day by day, how many classmates they had interacted with, however briefly, alongside their happiness and sense of belonging.
• Studies 2A and 2B: Students and members of the community counted their daily interactions with both strong ties and weak ties, including simple greetings.
• Design: Repeated daily reports: each person is compared with themselves, on busier and quieter days.
• Access: Subscription-only. This summary uses the published abstract, the authors’ companion experiment, and the account of the method in later research.

Most research on relationships and happiness is about the people closest to us: partners, family, best friends. Gillian Sandstrom and Elizabeth Dunn noticed that this leaves out most of the people we actually talk to on a given day. The sociologist's term for them is weak ties: acquaintances, the familiar faces we know a little.1

What the researchers did

The studies used daily reports. In the first, university students recorded, each day, how many classmates they had interacted with, however minimal the interaction, along with how happy they felt and how much they felt they belonged. In the second pair, students and members of the wider community counted all of their daily interactions, with close and casual ties alike, including simple greetings.2

Daily reports allow a sharper question than a one-off survey. Rather than asking whether sociable people are happier, which could simply mean that happy people are sociable, the analysis can ask whether the same person is happier on days when they talk to more acquaintances than they usually do. The standard way to do that is to split each day's count into a person's own average and that day's departure from it.

What they found

In the first study, students experienced greater happiness and a greater sense of belonging on days when they interacted with more classmates than usual. In the second pair of studies, which counted every interaction, weak ties were again related to both social and emotional well-being, not only the close relationships that research usually centres on.

The companion experiment, published the same year, supplied the causal half. Customers at a coffee shop were asked either to have a genuine interaction with the barista, smiling, making eye contact and having a brief conversation, or to be as efficient as possible, with their money ready and no unnecessary talk. Those who had the genuine interaction left in a better mood and with a stronger feeling of belonging.3

Has it held up?

The idea has been tested again at the smallest possible scale. In Turkey, Gul Gunaydin and colleagues studied people commuting on university shuttle buses. Among 856 commuters, those who more often greeted, thanked or wished their driver well reported higher life satisfaction and more positive feelings, even after accounting for their personality and age. In an experiment with 265 more, people asked to greet, thank or wish the driver well, most of them exchanging about three words, felt better after the ride than people asked not to speak to the driver.2

The evidence on small interactions, from correlation to experiment

What this study cannot tell you

• Daily reports are still correlational. A good day might lead people to talk to more classmates, rather than the talking causing the good day. The companion experiment and later studies address this, but this paper alone cannot.
• Counts of interactions are self-reported, and a person in a good mood may remember or notice more of them.
• The samples were students and a community group in one country. The Turkish study extends it to a different culture.
• We could not read the paper. It is subscription-only; its method is described here from its abstract and from later research, and its own statistics are not reproduced.

What a speaker can take from it

We tend to think of speaking as something that matters in big moments: the presentation, the interview, the difficult conversation. This research points at the small ones. A greeting that becomes a sentence, a question to the person at the counter, a real exchange with the colleague you normally nod to.

These are not networking in any strategic sense. They are simply more moments in the day when you speak to someone and they speak back, and on the evidence, days with more of them are better days. They are also the easiest place to practise the thing that makes bigger conversations easier: starting.

This article summarises a subscription-only paper from its abstract and from the description of its method in Gunaydin et al. (2021). The barista experiment and the shuttle-bus results are from those papers. The network diagram and the equation are illustrations, not the paper’s own.

Measured

• Daily counts of interactions with classmates, acquaintances and close ties, reported by participants
• Daily happiness and sense of belonging

Inferred, not measured

• That weak-tie interactions cause better days: this paper is correlational; the causal evidence comes from the separate experiments

References

1. Sandstrom, G. M., & Dunn, E. W. (2014). Social interactions and well-being: the surprising power of weak ties. Personality and Social Psychology Bulletin, 40(7), 910–922. https://doi.org/10.1177/0146167214529799
2. Gunaydin, G., Oztekin, H., Karabulut, D. H., & Salman-Engin, S. (2021). Minimal social interactions with strangers predict greater subjective well-being. Journal of Happiness Studies, 22(4), 1839–1853. https://doi.org/10.1007/s10902-020-00298-6
3. Sandstrom, G. M., & Dunn, E. W. (2014). Is efficiency overrated? Minimal social interactions lead to belonging and positive affect. Social Psychological and Personality Science, 5(4), 437–442. https://doi.org/10.1177/1948550613502990