nodecovar-ergmTerm-35c93a8b: Covariance of undirected dyad values incident on each actor

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

Covariance of undirected dyad values incident on each actor

Description

This term adds one statistic equal to \sum_{i,j<k} y_{i,j}y_{i,k}/(n-2) . This can be viewed as a valued analog of the star(2) statistic.

Usage

# valued: nodecovar(center, transform)

Arguments

center	If center=TRUE , the y_{\cdot,\cdot} s are centered by their mean over the whole network before the calculation. Note that this makes the model non-local, but it may alleviate multimodailty.
transform	If transform="sqrt" , y_{\cdot,\cdot} s are repaced by their square roots before the calculation. This makes sense for counts in particular. If center=TRUE as well, they are centered by the mean of the square roots.

Note

Note that this term replaces nodesqrtcovar , which has been deprecated in favor of nodecovar(transform="sqrt") .

See Also

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

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

ergm documentation built on Aug. 27, 2025, 9:08 a.m.