# Chapter 11 Glossary

Great resource here.

Adjacent is when two vertices are connected by an edge. The vertices are also referred as neighbors.

Attributes are a characteristic of the node or edge that is often designated by color, size, or shape of the object. For example, a dashed line for an edge or a blue circle for a node.

Degree the number of nodes adjacent to the node under evaluation or the number of lines incident to it.

Deterministic is a algorithm that always produces the same layout for the same graph.

Diameter is the maximum number of edges.

Edges are ties, relations or connections between nodes. Edges are often designated as $$E$$.

Empty graph is a graph with no vertices or edges.

Indegree is the number of received ties.

Loops are edges the starting point and the end point is the same node.

Multigraph is one where there are multiple edges connecting the same two nodes.

Neighborhood of a vertex v in a graph G is the set of vertices adjacent to v. The neighborhood is denoted N(v). The neighborhood does not include v itself.

Networks

Network objects is a class of objects in R designed specifically for network analysis. They store an adjacency matrix or an edgelist as well as metadata.

Nodes are also actors or vertices. They are things like people, places, ideas that have some connection. In mathmatical formulas, they often take the variable $$N$$.

Outdegree the number of sent ties.

Directed networks

Sociogram is a graph of a network.

Trival graph a graph with only one vertex and no edges.

Weighted graph or edge-weighted graph is where the edge list contains a variable assigning the strength or “weight” of the connection.