Monday, July 27, 2015

209. Identity and altruism in networks

There are two reasons why it may be useful to employ concepts from network theory. One is to further analyse the notions of bonding and bridging capital mentioned in the preceding item in this blog. A second is that it may be useful to consider identity in terms of networks, as I suggested earlier (in item 10 of this blog).

Personal identity is then associated with positions in networks, and cultural identity with the structure of networks. 

A central feature of position is centrality. There are different types. One is degree centrality, defined as the number of direct ties one has. This yields power of influence. It yields preferential attachment: the more  direct connections one has the more attractive one is as a contact, and the more new connections one gets. This is a Matthew effect: the rich will get richer and the poor will get poorer. That is one form of the winner takes all phenomenon that I discussed in item 203.

Betweenness centrality is the extent that one sits on an intersection of paths between distant points (nodes) in the network. This yields power of intermediation or brokerage.

The strength of a tie has several dimensions: duration, dependence (which can be one-sided), investment in the tie, trust, and the number of activities involved in the tie

A central feature of network structure is of course the number of nodes. A second feature is the density of the network: the number of direct ties between nodes. If density is complete, every node has a direct tie to every other node. Then all nodes have equal, maximum degree centrality.

Now what would one prefer: dense, strong ties, or sparse, weak ones? Perhaps one’s intuition favours the first. And indeed: many direct ties yield access to many resources, and strong mutual dependence and trust yield stability.

However, there is the famous claim (proposed by Mark Granovetter) of the strength of weak ties: high density of the network, high centrality of position, and strong ties also carry disadvantages. They may tie one down, burdening capacity to deal with ties and limiting flexibility. 

Communities with dense and strong internal ties, and few ties with other communities, would most exhibit the parochial altruism discussed in preceding items. Personal identity then is also strongly tied to group identity.

Economically, this yields a danger of stagnation, due to a lack of variety. Over time, with strong ties cognitive distance will become small, and members have little novelty to share. For novelty, there should be newcomers to the community, or there should be outside ties. That requires a limitation of the parochiality of altruism. 

Structural holes are gaps in network structure: batches of nodes that are internally but not mutually connected. A special case is the small worlds structure, clusters with high density of strong internal ties and only few and weak ties between them. Ties between these batches require and stimulate altruism going beyond the parish. The internal ties yield bonding capital and the external ties yield bridging capital.

Those structures are ideal, both politically and economically. They yield internal cohesion of a community, with a large degree of trust, allowing for limited contracts, yielding low costs of contact and room for informality and improvisation. At the same time, economically, external ties yield impulses of variety to create novelty, and the diffusion and hence utilization of novelty. Politically, the internal ties allow for communal democracy, and the external ties yield a basis for the political scale advantages of integration discussed in item 207.

Perhaps this should be the model for the EU.