R: The m-separation criterion

msep {ggm} | R Documentation

## The m-separation criterion

### Description

`msep` determines whether two set of nodes are m-separated by a third set of nodes.

### Usage

    msep(a, alpha, beta, C = c())

### Arguments

`a` | An adjacency matrix, or a graph that can be a `graphNEL` or an `igraph` object or a vector of length 3e, where e is the number of edges of the graph, that is a sequence of triples (type, node1label, node2label). The type of edge can be `"a"` (arrows from node1 to node2), `"b"` (arcs), and `"l"` (lines).
`alpha` | A subset of the node set of `a`
`beta` | Another disjoint subset of the node set of `a`
`C` | A third disjoint subset of the node set of `a`

### Value

A logical value. `TRUE` if `alpha` and `beta` are m-separated given `C`. `FALSE` otherwise.

### Author(s)

Kayvan Sadeghi

### References

Richardson, T.S. and Spirtes, P. (2002) Ancestral graph Markov models. Annals of Statistics, 30(4), 962-1030.

Sadeghi, K. and Lauritzen, S.L. (2011). Markov properties for loopless mixed graphs. Submitted, 2011. URL http://arxiv.org/abs/1109.5909.

### See Also

`dSep`, `MarkEqMag`

### Examples

    H <-matrix(c(0,0,0,0,
    	         1,0,0,1,
    	         0,1,0,0,
    	         0,0,0,0),4,4)
    msep(H,1,4, 2)
    msep(H,1,4, c())

[Package ggm version 2.3 Index]