This seems to be correct for me, i.e.
g <- graph.formula(0--1--2, 3--4)
closeness(g)
[1] 0.3076923 0.3333333 0.3076923 0.2500000 0.2500000
shortest.paths(g)
[,1] [,2] [,3] [,4] [,5]
[1,] 0 1 2 Inf Inf
[2,] 1 0 1 Inf Inf
[3,] 2 1 0 Inf Inf
[4,] Inf Inf Inf 0 1
[5,] Inf Inf Inf 1 0
4/(1+2+5+5)
[1] 0.3076923
4/(1+1+5+5)
[1] 0.3333333
4/(5+5+5+1)
[1] 0.25
According to the formula in ?closeness, I assume that is right.
Best,
Gabor
On Wed, Dec 10, 2008 at 6:26 PM, Alvaro Graves Fuenzalida
<address@hidden> wrote:
Hi, I'm working with closeness centrality but there is something I don't get
if it's correcto or not:
If I have the following graph
0---1---2
the centrality is
0 -> 0.666667
1 -> 1.000000
2 -> 0.666667
which makes sense. However if I add another unconnected edge 3---4 then I
have
0 -> 0.307692
1 -> 0.333333
2 -> 0.307692
3 -> 0.250000
4 -> 0.250000
According to the documetation "If the graph is not connected, and there is
no path between two vertices, the number of vertices is used instead the
length of the geodesic", but still the numbers don't fit. Can somebody tell
me if there is a mistake or I misunderstood something?
Thanks in advance
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