aridProj: Compute the (maximal) arid or ancestral projection of a graph

In rje42/ADMGs2: Functions for Describing and Fitting Discrete Mixed Graphs

Compute the (maximal) arid or ancestral projection of a graph

Description

Compute the (maximal) arid or ancestral projection of a graph

Usage

aridProj(graph, maximal = TRUE, verbose = FALSE)

ancProj(graph, maximal = TRUE, directed = FALSE)

Arguments

graph	an ADMG as an object of class mixedgraph
maximal	should the projection computed be maximal?
verbose	logical: should additional output be given?
directed	logical: is graph an ADMG?

Details

The input graph should be a summary graph for ancProj, and an ADMG for aridProj.

Algorithm for aridProj(): compute the intrinsic closure of every vertex. Use this to obtain directed edges. Then add in bidirected edges for vertices not already adjacent. Then go through pairs and check if intrinsic closures are joined by a bidirected edge.

Algorithm for ancProj(): go through in a topological order and check no siblings are among ancestors. If there are at say v, then look for parents and siblings, recursively if the latter are also ancestors. Remove any bidirected edges from discovered vertices to v and add directed edges from them to v

If maximal graph asked for, then also check intrinsic closures of the pairs.

Functions

• ancProj(): obtain ancestral projection

rje42/ADMGs2 documentation built on Sept. 3, 2024, 7:39 p.m.