they may not be high in the formal hierarchy, their opinions are crucial to any action taken by the group - and the organisation. The core group is the prototypical social network in any organisation. The core individual's influence can be overt, as in people who become known as ‘fixers' or ‘movers' in a team, or subtler.
To take an example, the generals do not run the military, it's not run by the officers, the sergeants run it. That network of sergeants, or the head nurses in a hospital, is the real core group. They are the ones who get things done, and who drive organisational change. Identifying core people and core networks is a fundamental part of social network analysis. Organisational change is rarely successful when done as management mandate. To succeed, it has to be implemented at the social network level, but needs to be supported at the core group level.
Team members' attributes and behaviour differ according to their position in the informal network. Individuals with more connections are often exposed to more, and more diverse information. For instance, everyone hears the progress update at the meeting, but the people who share a smoke or a ride home swap the gossip. Highly connected individuals can be more influential, and may be more influenced by others. The roles adopted by individuals in the network will to a large extent depend on their personality, unless otherwise influenced by factors that force them to give up ingrained behaviour patterns.
SNA in Groups
Performing SNA in groups of any size can be entertaining and informative. Mapping the social connections generates curiosity and appeals to basic human needs for connection and feedback. There are a number of ways in which this can be done. The network can be presented as a 2D visualisation [fig. 1] derived from the numbers and strengths of connections between each node. Connection strength and reciprocity are represented by line thickness and arrowhead direction, respectively.
Recently, researchers like Benjamin Waber, a doctoral student at MIT, have experimented with live, real-time social network mapping. Waber's ‘reality mining' technique uses RFID equipped badges to log the location and duration of interactions between employees. The author has been discussing with colleagues at Nokia the possibility of using mobile phones for a similar purpose. The core group and the structure of the informal network become apparent very rapidly. Different patterns of interaction reveal different types of team, for instance the ‘pulsing star', indicating a very creative team - they spread out, and then regroup to share information. Waber can improve the density of informal networks by spotting weak areas and engineering connections between individuals, in a process dubbed ‘network tightening', which is his intuitive approach to social network stimulation.
Note that the types of connections mapped by Waber, in terms of who meets and communicates with whom, are non-emotive, unlike a questionnaire asking about levels of trust. The networks mapped are of neutral interaction and information exchange, and do not ask for subjective ratings of individuals by other individuals.
Mapping the social network of an organisation can have drawbacks. For instance, it can engender resentment among managers when it becomes clear they aren't the hub, or even a hub, of the network. Snowden and others recall incidents where management deliberately marginalised strongly connected individuals whose position in the hierarchy did not, they felt, entitle them to that role. For such ‘political' reasons, people will frequently rate their relationships with their seniors more positively than is in