In large social networks, even a few individual observations can become interdependent due to short path distances between nodes. Therefore, it is hard to disentangle the cause of changes in the network structure over time. Is this due to gradual behavioral shifts across the population, or do the decisions of a few individuals to rewire their networks drive large-scale changes? We revisit this question in a population-scale social network of the entire country of the Netherlands. Using a yearly snapshot of the family, work, school, household, and neighborhood connections of the whole population between 2011 and 2021, we find that the network is becoming sparser, with average social cohesion measured by closure declining by up to 10% over a decade. By following changes in the ego networks of people year after year, we observe a group of people with changes in the work, school, or neighborhood layers leading to a substantial drop in everyone’s ego network closure. Using a synthetic network model, we replicate this pattern by selectively rewiring the connections of a small subset of individuals, confirming our empirical observations. Our work helps in understanding large structural shifts in contemporary societies from a social network point of view, and gives a new multi-layer model of temporal social network evolution.

South Korea has undergone rapid social change in recent decades, often described as compressed modernity. This study examines how these transformations have shaped the size, composition, and structure of Koreans’ intimate personal networks, with a particular focus on the role of kin and non-kin ties in core discussion networks.

Traditionally, Korea’s strong family-oriented culture has emphasized kin ties, but economic prosperity, demographic shifts, and technological advances have fostered individualistic lifestyles. However, contemporary Korean individualism, shaped by Confucian and familial legacies, may differ from Western models. The sociologist Chang Kyung-sup characterizes it as “individualism without individuals” or “familial liberalism,” where the family remains the basic social unit.

Using four nationally representative surveys spanning three decades—the Survey of Consciousness and Values in Transitional Society (1996), the Survey of Social Order (2002), the Korean General Social Survey (2011), and the Culture and Attitudes in Everyday Life of Koreans Survey (2024)—we analyze trends in core discussion networks. These are the only national Korean surveys with an “important matter” name generator module, allowing for direct comparison over time.

Preliminary findings indicate a recent decline in network size, primarily due to a reduction in non-kin ties over the past decade, which has led to an increased proportion of kin ties. Additionally, network density has risen. These results suggest that despite sweeping social change, Koreans' intimate networks have become more tightly centered around family. We also explore evolving gender differences, as economic and cultural shifts likely affected women’s networks more than men’s.

This study focuses on the changes in the personal social network of young immigrants and foreign students and its impact on their subjective well-being during the first period of the COVID-19 pandemic. Data was collected in two waves: the same individuals were interviewed in the period before the first recorded coronavirus infection (early 2020) and during strict epidemiological restrictions (early 2021) in Hungary. Respondents with favourable sociodemographic characteristics (N=30) had extensive networks in both years, with only a slight decrease between the two data collections. Our data shows that although the average network size did not change significantly between the two data collections, changes in the network compositions show a decrease in the weaker ties to the host society, which implies an integration deficit for the studied population. The network size and the subjective well-being indicators did not show a correlation in the sample: regardless of an extended network, one can feel lonely. In the first period of the COVID-19 pandemic, the subjective well-being of those was better who, due to their personality, did not desire a large social network, but enjoyed the support of a stable network of emotionally close people. Regular and personal contact was important for being able to maintain subjective well-being during the pandemic, but the density of the micro-network was found to be a more important factor than its extent.

This study explores how Facebook relationship event posts affect the changes in newlyweds' social networks at different stages, including acquaintance, dating, cohabitation, and marriage. Using survey data and social media post records, we reconstruct key relationship events and examine how social media interactions change before and after these events.

We analyze whether relationship strength changes over time and identify key factors influencing these shifts. Using multilevel analysis, we consider the effects of individual factors (gender, age, education, personality), relationship factors (relationship type, mutual friends, shared interests), and interaction factors (post engagement, response rates).

This study offers insights into how newlyweds' social networks develop and how digital interactions shape intimate relationships. The findings contribute to a better understanding of social media’s role in influencing relationship dynamics in the digital era.