latentnetHRT {latentnetHRT}R Documentation

Latent position and cluster models for networks

Description

The package latentnet was originally developed, by Mark S. Handcock, Peter Hoff, Susan Shortreed, and Jeremy Tantrum, to implement Handcock, Raftery and Tantrum (2007), but has been substantially rewritten by Pavel Krivitsky to enhance the capabilities and implement the new specification given in Krivitsky and Handcock (2008). See also Krivitsky, Handcock, Raftery, Hoff (2007). The package latentnetHRT implements the original specification in Handcock, Raftery and Tantrum (2007) This corresponds to version 0.7 of the original latentnet. The new package latentnet, Version 2.0 and higher implements the new specification in this paper.

By way of context, the package statnet is used to fit linear exponential random network models, in which the probability of a given network, y, on a set of nodes is exp(theta{cdot}g(y))/c(theta), where g(y) is a vector of network statistics, theta is a parameter vector of the same length and c(theta) is the normalizing constant for the distribution. The ergm function can return either a maximum pseudo-likelihood estimate or an approximate MLE based on a Monte Carlo scheme. For details, see http://statnetproject.org.

The package latentnetHRT adds latent variable models to the traditional exponential random network models. These latent models are fit using the ergmm function.

The ergmm specifies models via: y ~ <model terms> where y is a network object. For the list of possible <model terms>, see the manual pages for terms.ergmm.

Arguments

... Specific to the latent variable model terms.

Value

ergmm returns an object of class ergmm that is a list.

References

Peter D. Hoff, Adrian E. Raftery and Mark S. Handcock. Latent space approaches to social network analysis. Journal of the American Statistical Association, Dec 2002, Vol.97, Iss. 460; pg. 1090-1098.

Mark S. Handcock, Adrian E. Raftery and Jeremy Tantrum. Model-Based Clustering for Social Networks. Journal of the Royal Statistical Society, Series A, 170(2), 301-354.

Pavel Krivitsky and Mark S. Handcock (2008). Fitting Latent Cluster Models for Social Networks with latentnet. {Journal of Statistical Software}, textbf{24}(5). http://www.jstatsoft.org/v24/i05/.

Pavel Krivitsky, Mark S. Handcock, Adrian E. Raftery and Peter Hoff. Representing Degree Distributions, Clustering, and Homophily in Social Networks With Latent Cluster Random Effects Models. Working Paper Number 71, Center for Statistics and the Social Sciences, University of Washington, August 2007.

See Also

ergmm, latent, latentcluster, sna, network, terms.ergmm

Examples

#
# Using Sampson's Monk data, lets fit a 
# simple latent position model
#
data(sampson)
#
# Get the group labels
samp.labs <- substr(get.vertex.attribute(samplike,"group"),1,1)
#
samp.fit <- ergmm(samplike ~ latent(k=2), burnin=10000,
                 MCMCsamplesize=2000, interval=30)
#
# See if we have convergence in the MCMC
mcmc.diagnostics(samp.fit)
#
# Plot the fit
#
plot(samp.fit,label=samp.labs, vertex.col="group")
#
# Using Sampson's Monk data, lets fit a latent clustering model
#
samp.fit <- ergmm(samplike ~ latentcluster(k=2, ngroups=3), burnin=10000,
                 MCMCsamplesize=2000, interval=30)
#
# See if we have convergence in the MCMC
mcmc.diagnostics(samp.fit)
#
# Lets look at the goodness of fit:
#
plot(samp.fit,label=samp.labs, vertex.col="group")
plot(samp.fit,pie=TRUE,label=samp.labs)
plot(samp.fit,density=c(2,2))
plot(samp.fit,contours=5,contour.color="red")
plot(samp.fit,density=TRUE,drawarrows=TRUE)
ergmm.add.contours(samp.fit,nlevels=8,lwd=2)
points(samp.fit$Z.mkl,pch=19,col=samp.fit$class)

[Package latentnetHRT version 0.7-18 Index]