Community Definition

The concept of community is really prominent in complex network analysis and a large field of research, given its importance.

What’s a community?

The definition of a community is not exactly fixed, but the authors overall say that a community is a group of nodes densely connected between them and sparsely connected with the rest of the network. Therefore, dense regions in a graph are what we usually consider a community.

Another way of defining a community is by saying that two nodes from the same community have a higher probability of being connected than they would have if they weren’t from the same community.

Communities appear naturally in several types of networks. Complex networks that represent the social relationships of several groups are one example of that. A college, for example, can generate a community, while a company can generate another one. In both cases, someone is more likely to be connected to someone who goes to the same college or job as them.

Types of communities

Communities can come in various shapes and forms depending on the phenomena we’re analyzing.

Regular communities

Regular communities are the ones we’ve been talking about until now. We have a structure where the nodes inside a community are more densely connected than the other nodes of the network.

We can have communities of different sizes, some being smaller ...