From Wikipedia, the free encyclopedia
Betweenness is a centrality measure of a vertex within a graph . Vertices that occur on many shortest paths between other vertices have higher betweenness than those that do not.
Definition
For a graph
G
:=
(
V
,
E
)
{\displaystyle G:=(V,E)}
with n vertices, the betweenness
C
B
(
v
)
{\displaystyle C_{B}(v)}
for vertex
v
{\displaystyle v}
is:
C
B
(
v
)
=
σ
s
≠
v
≠
t
∈
V
(
σ
s
t
(
v
)
)
(
n
−
1
)
(
n
−
2
{\displaystyle C_{B}(v)={\frac {\sigma _{s\neq v\neq t\in V}(\sigma _{st}(v))}{(n-1)(n-2}}}
Where
σ
s
t
(
v
)
=
1
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.
==
R
e
f
e
r
e
n
c
e
s
==
F
r
e
e
m
a
n
,
L
.
C
.
(
1977
)
A
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e
t
o
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a
s
u
r
e
s
o
f
c
e
n
t
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a
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r
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′′′′′
40
‴
,
35
−
−
41.
{\displaystyle \sigma _{st}(v)=1<math>iftheshortestpathfrom''s''to''t''passesthrough''v''and0otherwise.Seealso[[graphtheory]]measuresof[[distance(graphtheory)|distance]].==References==Freeman,L.C.(1977)Asetofmeasuresofcentralitybasedonbetweenness.''Sociometry'''''40''',35--41.}