Small-world index

The Humphries & Gurney (2008) small-world index sigma: observed transitivity and average shortest-path length compared with degree-preserving random graphs (sigma = (C/C_rand) / (L/L_rand); sigma > 1 indicates small-worldness). Computed on the binarised network. Ported from qgraph::smallworldness.

Usage

net_smallworld(x, n_rand = 100L, seed = NULL)

Arguments

x

A psychnet object or a square weighted adjacency matrix.

n_rand

Number of degree-preserving random graphs. Default 100.

seed

Optional integer for reproducibility of the random graphs.

Value

A tidy one-row data.frame (class psychnet_smallworld): smallworldness, transitivity, aspl, transitivity_rand, aspl_rand.

References

Humphries, M. D., & Gurney, K. (2008). PLoS ONE, 3(4), e0002051.

Examples

S <- 0.4^abs(outer(1:8, 1:8, "-"))
net_smallworld(ebic_glasso(cor_matrix = S, n = 400), n_rand = 50, seed = 1)
#>   smallworldness transitivity aspl transitivity_rand aspl_rand
#> 1              0            0    3              0.13  2.375385