.
In light of the two drastically different yet representative views on how social networks arise (Blau, 1977; Pescosolido and Rubin, 2000; Aldrich and Kim, 2007), networks can serve both as important opportunities and barriers to actor's performances and their realization of ends. Blau (1977) posits that people in modern society form integrative weak ties across heterogeneous social groups for pursuing more abundant opportunities. On the contrary, Pescosolido and Rubin (2000) argue that stable ties are hardly formed in modern society; instead, more temporal, contingent relationships prevail. The fundamental assumption of network analysis is that social processes generated by networks of social ties have important consequences both for individual actors and for the system within which they are embedded. In a word, behaviors or processes of actors and the system relate to the nature, structure, and interactions within and between networks. .
Core Concepts.
A given network is a system that can be decomposed into various units and their relationships. A network consists of two core elements - nodes and relationships among them. Nodes (or actors) can represent a wide variety of entities from individual persons, small groups, formal organizations, to systems of organizations and even states, nations. The specific feature of a node represents the level of analysis of within a network. In research on personal and organizational networks, a node generally possesses the capacity for rational action in relation to other nodes. Individual persons generally have an ability to act purposefully, but one can arguably assert that organizations can also make calculated decisions and choices that affect their members, other organizations, and even the broad institutional environment. Because of the capacity to act and achieve ends, the nodes of a social or organizational network are often replaced by actors in many studies.