What fraction of my friends are friends of each other?

$Cl_i(g)$ = #{kj in g | k, j in $N_i(g)$} / #{kj | k, j in $N_i(g)$}

Average clustering: $$Cl^{avg}(g) = \sum_i Cl_i(g)/n $$

Overall clusterig:

- $Cl(g)$ = $\sum_i$ #{kj in g | k, j in $N_i(g)$} / $\sum_i$ #{kj | k, j in $N_i(g)$}

Average and Overall clustering tend to 0, if max degree is bounded and network becomes larege:

- $Cl(g)$ = $\sum_i$ #{kj in g | k, j in $N_i(g)$} / $\sum_i$ #{kj | k, j in $N_i(g)$} is simply p

If degree is bounded, then p(n-1) is bounded

So p goes to 0 as n grows

Prison friendships

- 0.31 (MacRae 60) vs 0.0134 (G(n, p) model)

CO-authorships

- 0.15 math (Grossman 02) vs 0.00002
- 0.09 biology (Newman 01) vs 0.00001
- 0.19 econ(Goyal et al 06) vs 0.00002

www

- 0.11 for web links (Adamic 99) vs 0.0002