[igraph] igraph_barabasi_game doubt

[Guilherme Ferraz de Arruda]

Hi,

I am using the igraph library in C to generate Barabasi-Albert (the original model) networks that behaves as P(k) ~ k^(gamma), however when I tried to measure the gamma parameter (using http://tuvalu.santafe.edu/~aaronc/powerlaws/) but the estimated values are around 2.3~2.4 when the expected values should be near 3.

I am using the following code:

igraph_barabasi_game ( &graph, N, 1, m, 0, 0, 1, IGRAPH_UNDIRECTED, IGRAPH_BARABASI_PSUMTREE,0 );

for N =4000 and m=4.

Thanks in advance.

Guilherme.