L1centGROUP {L1centrality} | R Documentation |
Computes group L1 centrality or group L1 prestige for the specified group of vertices. For undirected graphs, the two measures are identical.
L1centGROUP(g, nodes, eta, mode, method)
## S3 method for class 'igraph'
L1centGROUP(
g,
nodes,
eta = NULL,
mode = c("centrality", "prestige"),
method = c("minimum", "maximum", "average")
)
## S3 method for class 'matrix'
L1centGROUP(
g,
nodes,
eta = NULL,
mode = c("centrality", "prestige"),
method = "minimum"
)
g |
An |
nodes |
A vector of integers. Each integer indicates the index of the vertex. |
eta |
An optional nonnegative multiplicity (weight) vector for (vertex)
weighted networks. The sum of its components must be positive. If set to
|
mode |
A character string. For an undirected graph, either choice gives the same result.
|
method |
A character string. It specifies the method of setting the edge
weight between the pseudo-vertex and the other vertices. Note that the S3
method for the
|
Given a group of vertices on a graph, we first construct a group reduced
graph by replacing the group of vertices by a single ‘pseudo-vertex’
(see group_reduce()
for the method of setting vertex multiplicities and
edge weights in the group reduced graph). The group
L1 centrality (prestige)
of this group is defined as the
L1 centrality (prestige)
of the pseudo-vertex in the group reduced graph.
A list consisting of two objects:
‘prominence’: The group
L1 centrality (if
mode = "centrality"
) or the group
L1 prestige (if
mode = "prestige"
) of the specified group of vertices.
‘label’: A vector of the vertex names specified by nodes
.
The function is valid only for connected graphs. If the graph is directed, it must be strongly connected. Multiple edges (edges with the same head and tail vertices) are not allowed, because they make the edge weight setting procedure confusing.
S. Kang. Topics in Non-Euclidean Dimension Reduction. PhD thesis, Seoul National University, 2025.
L1cent()
for L1
centrality/prestige, group_reduce()
for details on the minimum, maximum, and average methods.
# Group L1 centrality of the 'Spider-Man' series
vertex_weight <- igraph::V(MCUmovie)$worldwidegross
L1centGROUP(MCUmovie, nodes = c(16,23,27), eta = vertex_weight)