ergm package
that counts the number of graphlets in the network for a given graphlet type.
graphletCount(g)graphletCount term. The
question that the change score function of this term answers is: how do
the number of graphlets of type G_i change when an edge is flipped in
the network? This term has an optional argument, g. g is a
vector of distinct integers representing the list of graphlets to be
evaluated during the estimation of model coefficients. When this argument
is not provided, all graphlets are evaluated by default. The term adds one
network statistic to the model for each element in g. This term is
defined for the 30 graphlets with up to 5 nodes. Therefore, g accepts
values between 0 and 29. Values outside this range are ignored.
ergm is used to fit linear
exponential random graph models, in which the
probability of a given network, $y$, on a set of nodes
is $\exp{\theta *
g(y)}/c(\theta)$, where $g(y)$ is a vector of network
statistics for $y$, $\theta$ is a parameter vector of the same
length and $c(\theta)$ is the normalizing constant for the distribution.The network statistics $g(y)$ are entered as terms in the
function call to ergm. The ergm package contains
a wide range of terms. For the details on the possible
ergm-terms.
The ergm.userterms package provides a template for
adding new terms. The terms can be used throughout the ergm package
and behave identically to the supplied terms.