Re: [igraph] mismatched closeness values in R

[Gábor Csárdi]

On Fri, Dec 20, 2013 at 1:05 PM, Ju-Sung Lee <address@hidden> wrote:
> The results igraph R's closeness() and centralization.closeness()$res are
> different.  It appears closeness() uses the sum of shortest path lengths
> whereas centralization.closeness() uses the average (before the inversion).
> Was this intentional?

I guess so. Centralization means maximization imho, and if you invert
the average distance, then you would need to minimize. But I agree I
can be confusing.

> If so, it should probably be in the documentation.

Agreed.

> Also, the documentation is confusing.  It states the function employs the
> average length of shortest paths (which is what centralization.closeness()
> uses) but the formula does not reflect this (but closeness() is consistent
> with formula).

If _does_ employ the average length of shortest paths. And then it
inverts it, AFAIR.

> This was found under igraph_0.6.5-2 (I haven't upgraded my R yet so I don't
> know if this was fixed in igraph_0.6.6 but the README doesn't report any of
> this).

Which README is this?

Gabor

> Thanks.
>
> Jay
>
>
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