Use this if you are using igraph from R
The authority scores of the vertices are defined as the principal eigenvector of t(A)*A, where A is the adjacency matrix of the graph.
authority_score(graph, scale = TRUE, weights = NULL, options = arpack_defaults)
| graph | The input graph. | 
| scale | Logical scalar, whether to scale the result to have a maximum score of one. If no scaling is used then the result vector has unit length in the Euclidean norm. | 
| weights | Optional positive weight vector for calculating weighted
scores. If the graph has a  | 
| options | A named list, to override some ARPACK options. See
 | 
For undirected matrices the adjacency matrix is symmetric and the
authority scores are the same as hub scores, see
hub_score.
A named list with members:
| vector | The authority/hub scores of the vertices. | 
| value | The corresponding eigenvalue of the calculated principal eigenvector. | 
| options | Some information about the ARPACK computation, it has
the same members as the  | 
J. Kleinberg. Authoritative sources in a hyperlinked environment. Proc. 9th ACM-SIAM Symposium on Discrete Algorithms, 1998. Extended version in Journal of the ACM 46(1999). Also appears as IBM Research Report RJ 10076, May 1997.
hub_score, eigen_centrality for
eigenvector centrality, page_rank for the Page Rank
scores. arpack for the underlining machinery of the
computation.
## An in-star g <- make_star(10) hub_score(g)$vector authority_score(g)$vector ## A ring g2 <- make_ring(10) hub_score(g2)$vector authority_score(g2)$vector