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Graph Metrics

Quantitative measures that describe the structure of a graph or the role of individual vertices and edges within it.

Centrality

How important is a vertex?

Metric Complexity What it measures

Betweenness Centrality

O(VE) unweighted; O(VE + V(V+E) log V) weighted

How often a vertex lies on shortest paths between other vertices. High betweenness = bridge or bottleneck.

Closeness Centrality

O(V) per vertex given a pre-computed distance map

Reciprocal of the sum of shortest distances to all other vertices. High closeness = can reach everyone quickly.

Degree Centrality

O(1) per vertex

Number of connections (in, out, or total). Simple but effective for many networks.

PageRank

O(V + E) per iteration

Importance based on incoming links (recursive: a link from an important page counts more). Used by web search engines.

Distance and structure

Metric What it measures

Eccentricity

Maximum distance from a vertex to any other. The minimum eccentricity across all vertices is the graph’s radius; the maximum is the diameter.

Geodesic Distance

Mean shortest-path distance from a vertex. Low mean = centrally located.

Clustering Coefficient

Fraction of a vertex’s neighbor pairs that are also connected to each other. High clustering = tight-knit local community.

Profile / Wavefront / Bandwidth

Sparse-matrix metrics used to evaluate vertex orderings for numerical solvers.

Graph-level statistics

Metric What it measures

Core Numbers

k-core decomposition: assigns each vertex the largest k such that it belongs to a subgraph where every vertex has degree >= k. Useful for identifying dense substructures. A weighted variant is available.

Most distance-based metrics (eccentricity, geodesic_distance, closeness_centrality) consume a pre-computed distance map and therefore don’t fit a single complexity figure — the cost is dominated by the shortest-paths run (Dijkstra per vertex, Floyd-Warshall, or Johnson) that you run first.