Key Points
- Researchers found that indirect social connections significantly influence the adoption of innovations.
- The experiment demonstrated that second-circle influences have about two-thirds of the impact of direct contacts.
- More than 590 participants were studied in over 20 sessions to analyze innovation diffusion.
- Indirect influences, such as “friends of friends,” can shape individual decision-making processes.
A team of researchers from the Instituto de Física Interdisciplinar y Sistemas Complejos (IFISC), Universidad Carlos III de Madrid (UC3M), and Universidad Politécnica de Madrid (UPM) has experimentally demonstrated that indirect connections in social networks play a significant role in the adoption of innovations. The findings, published in PNAS Nexus, reveal that the influence of indirect contacts—such as friends of friends—accounts for about two-thirds of the impact of direct contacts in the second circle of influence and one-third in the third circle.
The research team experimented with over 590 participants across 20 sessions to analyze how innovations spread in social networks. According to Anxo Sanchez, a researcher at UC3M’s Grupo Interdisciplinar de Sistemas Complejos (GISC), this is the first controlled experiment to investigate the effects of indirect connections on innovation adoption.
In the experiment, participants were asked to reach a consensus by choosing between two colors, representing “tradition” and “innovation.” Manuel Miranda, IFISC researcher and the study’s first author, explains that participants experienced pressure from their direct contacts and those in their wider social network.
The experiment was designed in four different settings, allowing participants to see the choices made by both their direct contacts (“friends”) and indirect contacts (“friends of friends”). The researchers then used a mathematical model to assess how influence decreases with social distance, revealing that indirect contacts have a measurable and significant impact on decision-making.
Ernesto Estrada, a researcher at IFISC, emphasized that the study challenges the common assumption that only direct connections determine the dynamics of innovation adoption. The study shows that second and third circles of influence also play an important role in shaping behaviors and choices. These findings have wide-ranging implications for understanding how ideas, behaviors, and technologies spread within society.
This interdisciplinary work combines experimental methods with advanced mathematical modeling, offering insights into the complex social influence processes in the diffusion of innovations. According to María Pereda, a researcher at UPM, while the study treats all “friends” as an indistinguishable group, future research will focus on predicting influence at a more specific, individual level.
The researchers conclude that their findings open new avenues for investigating how innovations spread through social networks. They suggest that strategies aimed at accelerating the adoption of new ideas or technologies should consider not just direct connections but also the broader network of indirect influences.
