psych (version 1.0-61)

structure.graph: Draw (using Graphviz) a structural equation model specified by two measurement models and a structural model

Description

Graphic presentations of structural equation models are a very useful way to conceptualize sem and confirmatory factor models. Given a measurement model on x (xmodel) and on y (ymodel) as well as a path model connecting x and y (phi), draw the graph. If ymodel is not specified, just draw the measurement model (xmodel + phi).

Input can be specified as matrices or the output from factanal, factor.pa, or a rotation package such as GPArotation.

Usage

structure.graph(xmodel, ymodel = NULL, Phi = NULL, out.file = NULL, labels = NULL, cut = 0.3, simple = TRUE, size = c(8, 6), node.font = c("Helvetica", 14), edge.font = c("Helvetica", 10), rank.direction = c("RL", "TB", "LR", "BT"), digits = 1, title = "Structural model", ...)

Arguments

xmodel

a factor model on the x variables.

ymodel

a factor model on the y variables (can be empty)

Phi

A matrix of directed relationships. Lower diagonal values are drawn. If the upper diagonal values match the lower diagonal, two headed arrows are drawn.

out.file

name a file to send dot language instructions.

labels

variable labels if not specified as colnames for the matrices

cut

Draw paths for values > cut

simple

Just draw one path per x or y variable

size

page size of graphic

node.font

font type for graph

edge.font

font type for graph

rank.direction

Which direction should the graph be oriented

digits

Number of digits to draw

title

Title of graphic

...

other options to pass to Rgraphviz

Value

• A graphic structural diagram

Details

The output can be directed to an output file for post processing using the dot graphic language.

See Also

fa.graph, omega.graph, sim.structural

Examples

fx <- matrix(c(.9,.8,.6,rep(0,4),.6,.8,-.7),ncol=2)
fy <- matrix(c(.6,.5,.4),ncol=1)
Phi <- matrix(c(1,0,0,0,1,0,.7,.7,1),ncol=3,byrow=TRUE)
structure.graph(fx,fy,Phi)