b2nodematch-ergmTerm-126ff8a2: Nodal attribute-based homophily effect for the second mode in...

In ergm: Fit, Simulate and Diagnose Exponential-Family Models for Networks

Nodal attribute-based homophily effect for the second mode in a bipartite network

Description

This term is introduced in Bomiriya et al (2014). With the default alpha and beta values, this term will simply be a homophily based two-star statistic. This term adds one statistic to the model unless diff is set to TRUE , in which case the term adds multiple network statistics to the model, one for each of (a subset of) the unique values of the attr attribute.

Usage

# binary: b2nodematch(attr, diff=FALSE, keep=NULL, alpha=1, beta=1, byb1attr=NULL,
#                     levels=NULL)

Arguments

diff	by default, one statistic will be added to the model. If diff is set to TRUE, one statistic will be added for each unique value of the attr attribute
keep	deprecated
alpha, beta	optional discount parameters both of which take values from ⁠[0, 1]⁠, only one should be set at one time
byb2attr	specifies a second mode categorical attribute. Setting this argument will separate the orginal statistics based on the values of the set second mode attribute— i.e. for example, if diff is FALSE , then the sum of all the statistics for each level of this second-mode attribute will be equal to the original b1nodematch statistic where byb2attr set to NULL .
levels	select a subset of attr values to include. (See Specifying Vertex attributes and Levels (?nodal_attributes) for details.)
attr	a vertex attribute specification (see Specifying Vertex attributes and Levels (?nodal_attributes) for details.)

Details

If an alpha discount parameter is used, each of these statistics gives the sum of the number of common first-mode nodes raised to the power alpha for each pair of second-mode nodes with that attribute. If a beta discount parameter is used, each of these statistics gives half the sum of the number of two-paths with two second-mode nodes with that attribute as the two ends of the two path raised to the power beta for each edge in the network.

Note

This term can only be used with undirected bipartite networks.

The argument keep is retained for backwards compatibility and may be removed in a future version. When both keep and levels are passed, levels overrides keep.

See Also

ergmTerm for index of model terms currently visible to the package.

\Sexpr[results=rd,stage=render]{ergm:::.formatTermKeywords("ergmTerm", "b2nodematch", "subsection")}

ergm documentation built on Oct. 7, 2024, 5:08 p.m.