Daniel Monsivais

Sex differences in social focus across the life cycle in humans.

Age and gender are two important factors that play crucial roles in the way organisms allocate their social effort. In this study, we analyse a large mobile phone dataset to explore the way life history influences human sociality and the way social networks are structured. Our results indicate that these aspects of human behaviour are strongly related to age and gender such that younger individuals have more contacts and, among them, males more than females. However, the rate of decrease in the number of contacts with age differs between males and females, such that there is a reversal in the number of contacts around the late 30s. We suggest that this pattern can be attributed to the difference in reproductive investments that are made by the two sexes. We analyse the inequality in social investment patterns and suggest that the age- and gender-related differences we find reflect the constraints imposed by reproduction in a context where time (a form of social capital) is limited.

Communication with Family and Friends across the Life Course

Each stage of the human life course is characterised by a distinctive pattern of social relations. We study how the intensity and importance of the closest social contacts vary across the life course, using a large database of mobile communication from a European country. We first determine the most likely social relationship type from these mobile phone records by relating the age and gender of the caller and recipient to the frequency, length, and direction of calls. We then show how communication patterns between parents and children, romantic partner, and friends vary across the six main stages of the adult family life course. Young adulthood is dominated by a gradual shift of call activity from parents to close friends, and then to a romantic partner, culminating in the period of early family formation during which the focus is on the romantic partner. During middle adulthood call patterns suggest a high dependence on the parents of the ego, who, presumably often provide alloparental care, while at this stage female same-gender friendship also peaks. During post-reproductive adulthood, individuals and especially women balance close social contacts among three generations. The age of grandparenthood brings the children entering adulthood and family formation into the focus, and is associated with a realignment of close social contacts especially among women, while the old age is dominated by dependence on their children.

Absence makes the heart grow fonder: social compensation when failure to interact risks weakening a relationship

Social networks require active relationship maintenance if they are to be kept at a constant level of emotional closeness. For primates, including humans, failure to interact leads inexorably to a decline in relationship quality, and a consequent loss of the benefits that derive from individual relationships. As a result, many social species compensate for weakened relationships by investing more heavily in them. Here we study how humans behave in similar situations, using data from mobile call detail records from a European country. For the less frequent contacts between pairs of communicating individuals we observe a logarithmic dependence of the duration of the succeeding call on the time gap with the previous call. We find that such behaviour is likely when the individuals in these dyadic pairs have the same gender and are in the same age bracket as well as being geographically distant. Our results indicate that these pairs deliberately invest more time in communication so as to reinforce their social bonding and prevent their relationships decaying when these are threatened by lack of interaction.

Tracking urban human activity from mobile phone calling patterns

Timings of human activities are marked by circadian clocks which in turn are entrained to different environmental signals. In an urban environment the presence of artificial lighting and various social cues tend to disrupt the natural entrainment with the sunlight. However, it is not completely understood to what extent this is the case. Here we exploit the large-scale data analysis techniques to study the mobile phone calling activity of people in large cities to infer the dynamics of urban daily rhythms. From the calling patterns of about 1,000,000 users spread over different cities but lying inside the same time-zone, we show that the onset and termination of the calling activity synchronizes with the east-west progression of the sun. We also find that the onset and termination of the calling activity of users follows a yearly dynamics, varying across seasons, and that its timings are entrained to solar midnight. Furthermore, we show that the average mid-sleep time of people living in urban areas depends on the age and gender of each cohort as a result of biological and social factors.

Network of families in a contemporary population: regional and cultural assortativity

Using a large dataset with individual-level demographic information of almost 60,000 families in contemporary Finland, we analyse the regional variation and cultural assortativity by studying the network between families and the network between kins. For the network of families the largest connected component is found to consist of around 1000 families mostly originated from one single region in Western Finland. We characterize the networks in terms of the basic structural properties. In particular, we focus on the k-cores and the presence of transitive triangles. Clustering in the networks is found to result from homophily by language and religious affiliations. The large network fragments appear to be small-worlds. We also compare the fragments in the kin network with respect to the average coefficient of relationship. The measures of assortativity are able to distinguish the families in terms of their regions of origin. Overall, we distinguish between two patterns of regional effects, the ‘metropolitan’ and the ‘cultural’ pattern.

Social Physics: Understanding Human Sociality in Communication Networks

In this brief review, we discuss some recent findings of human sociality in contemporary techno-social networks of interacting individuals. Here we will focus on a few important observations obtained by analysing mobile communication data of millions of users in a European country participating in billions of calls and text messages over a period of one year. In addition to the description of the basic structure of the network in terms of its topological characteristics like the degree distribution or the clustering coefficient, the demographic information of the users have been utilized to get deeper insight into the various facets of human sociality related to age and gender as reflected in the communication patterns of users. One of the observations suggests that the grandmothering effect is clearly visible in these communication patterns. In addition it is found that the number of friends or connections of a user show a clear decaying trend as a function of the user’s age for both genders. Furthermore, an analysis of the most common location of the users shows the effect of distance on close relationships. As computational analysis and modelling are the two key approaches or tools of modern ‘Social Physics’ we will very briefly discuss the construction of a social network model to get insight into how plausible microscopic social interaction processes translate to meso- and macroscopic socially weighted network structures between individuals.