Chapter 7 Networks (1).pdf

Chapter 7 Networks 7.1 The friendship paradox Friendship paradox = people have fewer friends on average than their friends do on average. 7.2 Personal networks Personal network = a network presenting all the ties that a certain person (ego) has to others (alters). Graph (also sociogram) = a visual...

Chapter 7 Networks 7.1 The friendship paradox Friendship paradox = people have fewer friends on average than their friends do on average. 7.2 Personal networks Personal network = a network presenting all the ties that a certain person (ego) has to others (alters). Graph (also sociogram) = a visual representation of relations between actors in a network. - Nodes = actors within the network. In social networks, these are often individuals. (A, B, C, D) - Edges = the ties in the network. (from A to B, etc.) - Dyads = each (possible) relationship between ego (A) and alter (B, C, D). Degree of separation = the number of steps from ego to alter Types of ties: - Undirected ties (Figure 7.1 and Figure 7.2) - Directed ties (aka arcs)= ties in which the direction of the relationship between actors is specified (Figure 7.3) Directed graph = digraph Reciprocal relations = two-sided, symmetrical relations (there is an arc from Person 1 to Person 2, but also an arc from Person 2 to Person 1). Asymmetrical relations = there is only one arc between two people ( Person 2 nominated Person 3 as a friend, but not vice versa) Adjacency matrix = a matrix representing who has a relation to whom in a network. Indegree = the number of nominations a person receives from others. Outdegree = the number of nominations a person makes. Another distinction between ties, based on the degree of emotional closeness, frequency of interaction and reciprocity between two persons: - Strong ties = positive relationships in which people feel emotionally close to one another, trust each other and help each other out when needed - Weak ties = a more superficial or instrumental relationship between two people who see each other not that often and are emotionally less close to one another. Some scholars have proposed a “middle way” between these two extremes: five categories of tie strength, ordered in hierarchical network layers of tie strength between ego and alter. 1. Core network = “strongest” social ties = the most valued and intimate ties, such as with the spouse and a few best friends. 2. Sympathy network = strong ties and include the core network, but also add to this some ties that are not perceived to be as intimate as in the core network; it adds the wider circle of close family members and other friends. 3. Affinity network = adds peers, more-distant family members and others with whom people have relatively frequent contact. 4. Active network = includes the total number of persons with whom a person maintains an active relation. 5. Total personal network = entire personal network; it includes all strong ties, but also people merely known on a first name basis and with whom people have hardly any contact. 7.3 Network size and hubs Name generator = a survey question which asks the respondent to mention the names or initials of alters in their personal network. Hub = highly connected central nodes in a network. Hubs in personal networks: The distribution of personal network size follows a power law (highly skewed, long tail). A small number of individuals (hubs) have very many social ties. 7.4 Network density and transitivity Network density = the ratio of all realized ties in a network to the number of all possible ties in the same network. Triad = a network of three actors and the (possible) ties between them. Triadic closure (aka transitivity) = the situation in which the two alters of one ego are also connected to each other. Forbidden triad = a triad in which ego A has strong ties to alters B and C, but in which no tie exists between B and C. Transitivity tendency: If ego A has ties to alters B and C, then B and C are more likely to be (positively) connected compared with the situation in which ego A has a tie to either B or C (or to neither). In simple language: your connections likely know each other as well. There are three mechanisms of social tie-formation that explain the driving forces behind the transitivity tendency in core networks: 1. Meeting opportunities: Because ego A has strong ties to both B and C, it means she often interacts with B and C. This could mean that B and C share the same context as A, such as attending the same school or living in the same neighborhood, and therefore they also know each other. But it could also mean that B and C meet each other because they often interact with ego A (e.g., they are invited by ego A to her parties). Either way, meeting opportunities for B and C are high and one would expect transitivity in core networks. 2. Homophily: For example, friends are chosen because they share the same political or religious views and opinions, or belong to the same ethnic group. For this reason, ego A will probably be quite similar to both B and C. But that also means that B and C are quite similar to one another and therefore they find each other more attractive than a random stranger. 3. Structural balance: Ego A will be uncomfortable having friends B and C who are not having such positive ties with each other and, in particular, when her friends have a negative relationship. Scholars have argued that this unbalanced situation creates psychological strain for ego A and she will strive towards a balanced network, in which her friends B and C maintain a mutually positive relation. (see Chapter 8 Groups for information on these mechanism) It is helpful to use the simple dichotomy between strong ties and weak ties here: 1. Meeting opportunities: If ego A has weak ties to alters B and C, it means she less often interacts with them than if these had been strong ties. Hence, there are fewer opportunities for B and C to meet each other than if they had belonged to the core network of ego A. 2. Homophily: In the case of weak ties, people do not have a strong preference to interact with others who are similar to them. Such weak relations are more “superficial” and “instrumental,” as with neighbors or acquaintances. 3. Structural balance: In the case of weak ties, people are not so concerned that their connections are not mutually befriended or don’t know each other, as they are in the case of their most intimate social ties. Conclusion: Tie-strength between ego A and alters B and C moderates the transitivity tendency. In other words, the stronger the tie of ego A to alter B and C, the more likely it is that B and C are connected too.. 7.5 The small-world phenomenon Small-world phenomenon (aka six degrees of separation) = in large-scale contemporary societies, two randomly chosen individuals are personally connected in only a few steps (around 5–6 steps on average), via their friends, acquaintances and family. Community = a cluster of nodes that are more connected internally than externally, either directly and/or indirectly. Community-bonding ties = ties between people within the same community. Community-bridging ties = ties between people from different communities. Small-world network = a network that is characterized by a high level of local clustering and low average path length. Strength-of-weak-ties = weak ties more often create bridges to other communities than do strong ties. 7.6 Network change: loss-of-community? Loss-of-community: the tie-strength in personal networks has reduced and that people tend to have weaker rather than stronger ties. 7.7 Networks and social cohesion Social cohesion = the degree to which individuals and groups have (strong) positive relationships with each other, as opposed to no/neutral relationships or (strong) negative relationships. - There is order, trust, solidarity, social support and cooperation between people. - The opposite of a fragmented, disintegrated society, in which there are many conflicts, negative ties, distrust and uncooperative behavior. - The cohesiveness of social structures is not a matter of either/or but one of degree. - The more common negative ties are in personal networks, the lower the social cohesion in society. Three possible relationships between two actors in a population: Positive relationships (+) = people tend to help each other, cooperate and trust each other—although the extent to which this is the case depends on tie-strength; all sorts of relationships—strong and weak—which are generally evaluated as positive between two persons. Negative relationships (-) = two persons have a conflict, or they dislike each other, or don’t trust the other person; In weakly negative relations: (1) persons are not willing to help each other, (2) they put some effort into harming and obstructing the goals of the other person, (3) they tend to distrust each other. When the tie becomes more strongly negative, the distrust is higher and efforts to harm or obstruct the other also increase. No/neutral relationships = neither positive nor negative; people do not know each other or they are not friends, but are not enemies either. Personal network cohesion = the degree to which someone’s personal network consists of (strong) positive relationships as opposed to no/neutral relationships or even (strong) negative relationships. 7.8 Networks and social capital Social capital paradigm = perspective according to which social networks have some sort of value. - There does not exist a single social capital theory, in the sense of a single coherent set of propositions; rather, there are multiple social capital theories. - The social capital theories focus on different outcomes; it is not the case that these social capital theories explain the same thing. Social norms Network closure = highly connected, dense, network. Network closure and norms proposition: The degree of closure in a certain network has a positive effect on the conformity to the social norms of that network. Trust Tie strength and trust proposition: The more positive the relationship between ego and alter, the more they trust each other. Network closure and trust proposition: The higher the degree of closure in the network shared by ego and alter, the more ego and alter trust each other. - This type of trust is called particularized trust, or thick trust, and it is distinguished from generalized trust, or thin trust. Social ties and generalized trust proposition: The more social interactions people have with friends, family members and other community members, the stronger their generalized trust. Health and well-being Network cohesion and health proposition: The higher someone’s network cohesion, the better their health and well-being. Network health and health proposition: The better the health and well-being of people’s network ties, the better their own health and well-being.