Hi-

THanks. I pretty mush said that. But the (darn their curiosity!) student wanted to know WHY the negative results appear.

J

On Mon, Sep 28, 2015 at 3:43 PM, Vincenzo Nicosia <[log in to unmask]> wrote:

On Mon, Sep 28, 2015 at 03:21:31PM -0400, Jordi Comas wrote:

[cut]

> So, can someone help me out? To my eyes, the Bonacich algoritihim sums up

> the centrality score of each node by weighting each node. How can and

> additive series get a negative score?

> Thanks!

> Jordi

> (cookies in the mail for you for good answer. :) )

The problem is that if \beta is larger than the inverse of the largest

eigenvalue of the adjancency matrix, the sum which defines the

centrality scores does not converge any more. One of the practical

consequences is that the negative values will appear here and there in

your eigenvector, but the basic message is that the results you get

for your centrality scores loose any meaning.

My2Cents

Enzo

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[ Enzo Nicosia - School of Mathematical Sciences - Queen Mary UL ]

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