cug.test: Univariate Conditional Uniform Graph Tests

In sna: Tools for Social Network Analysis

Univariate Conditional Uniform Graph Tests

Description

cug.test takes an input network and conducts a conditional uniform graph (CUG) test of the statistic in FUN, using the conditioning statistics in cmode. The resulting test object has custom print and plot methods.

Usage

cug.test(dat, FUN, mode = c("digraph", "graph"), cmode = c("size", 
    "edges", "dyad.census"), diag = FALSE, reps = 1000, 
    ignore.eval = TRUE, FUN.args = list())

Arguments

dat	one or more input graphs.
FUN	the function generating the test statistic; note that this must take a graph as its first argument, and return a single numerical value.
mode	graph if dat is an undirected graph, else digraph.
cmode	string indicating the type of conditioning to be applied.
diag	logical; should self-ties be treated as valid data?
reps	number of Monte Carlo replications to use.
ignore.eval	logical; should edge values be ignored? (Note: TRUE is usually more efficient.)
FUN.args	a list containing any additional arguments to FUN.

Details

cug.test is an improved version of cugtest, for use only with univariate CUG hypotheses. Depending on cmode, conditioning on the realized size, edge count (or exact edge value distribution), or dyad census (or dyad value distribution) can be selected. Edges are treated as unvalued unless ignore.eval=FALSE; since the latter setting is less efficient for sparse graphs, it should be used only when necessary.

A brief summary of the theory and goals of conditional uniform graph testing can be found in the reference below. See also cugtest for a somewhat informal description.

Value

An object of class cug.test.

Author(s)

Carter T. Butts [e-mail]

References

Butts, Carter T. (2008). “Social Networks: A Methodological Introduction.” Asian Journal of Social Psychology, 11(1), 13–41.

See Also

cugtest

Examples

#Draw a highly reciprocal network
g<-rguman(1,15,mut=0.25,asym=0.05,null=0.7)

#Test transitivity against size, density, and the dyad census
cug.test(g,gtrans,cmode="size")
cug.test(g,gtrans,cmode="edges")
cug.test(g,gtrans,cmode="dyad.census")

sna documentation built on Sept. 11, 2024, 8:45 p.m.