qgraph is a package that can be used to plot several types of graphs. It is mainly aimed at visualizing relationships in (psychometric) data as networks to create a clear picture of what the data actually looks like.
Its most important use is to visualize correlation matrices as a network in which each node represents a variable and each edge a correlation. The color of the edges indicate the sign of the correlation (green for positive correlations and red for negative correlations) and the width indicate the strength of the correlation. Other statistics can also be used in the graph as long as negative and positive values are comparable in strength and zero indicates no relationship.
qgraph also comes with various functions to visualize other statistics and even perform analyses, such as EFA, PCA, CFA and SEM. The stable release of qgraph is available at CRAN, the developmental version of qgraph is available at GitHub and finally an article introducing the package in detail is available in the Journal of Statistical Software.
tikzdevice hotfix: Unfortunatly the tikzdevice package has been removed from CRAN. Because of this saving the plot in LaTeX format including mouseover tooltips is no longer supported in the stable release version. A short wrapper function can be downloaded here, sourcing this script will give the qgraph.tikz() function, which should work exactly the same as qgraph used to work with the filetype=”tex” argument.