By default, this term adds one statistic to the model equal to the number of triangles
in the network. For an undirected network, a triangle is defined to be any
set \(\{(i,j), (j,k), (k,i)\}\) of three edges. For a directed network, a
triangle is defined as any set of three edges \((i{\rightarrow}j)\)
and \((j{\rightarrow}k)\) and either \((k{\rightarrow}i)\)
or \((k{\leftarrow}i)\) . The former case is called a "transitive
triple" and the latter is called a "cyclic triple", so in the case of a
directed network, triangle equals ttriple plus ctriple
--- thus at most two of these three terms can be in a model.
# binary: triangle(attr=NULL, diff=FALSE, levels=NULL)# binary: triangles(attr=NULL, diff=FALSE, levels=NULL)
quantitative attribute (see Specifying Vertex attributes and Levels (?nodal_attributes) for details.) If attr is specified and diff is FALSE ,
then the count is restricted to those triples of nodes with
equal values of the vertex attribute specified by attr . If attr is specified and diff is TRUE ,
then one statistic is added for each value of attr ,
equal to the number of triangles where all three nodes have that value of the attribute.
this optional argument controls which levels of the attribute should be included and which should be excluded. (See Specifying Vertex
attributes and Levels (?nodal_attributes) for details.)
ergmTerm for index of model terms currently visible to the package.
ergm:::.formatTermKeywords("ergmTerm", "triangle", "subsection")