nodecovar-ergmTerm {ergm}

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.

Keywords

directed, valued