lfhtcID {SEMID}

Determines which edges in a latent digraph are LF-HTC-identifiable.

Description

Uses the latent-factor half-trek criterion to determine which edges in a latent digraph are generically identifiable.

Usage

lfhtcID(graph)

Arguments

graph

a LatentDigraph object representing the latent-factor graph. All latent nodes in this graph should be source nodes (i.e. have no parents).

Value

returns a list with 8 components:

solvedParents

a list whose ith element contains a vector containing the subsets of parents of node i for which the edge j->i could be shown to be generically identifiable.

unsolvedParents

as for solvedParents but for the unsolved parents.

identifier

a function that takes a (generic) covariance matrix corresponding to the graph and identifies the edges parameters from solvedParents and solvedSiblings. See htcIdentifyStep for a more in-depth discussion of identifier functions.

graph

a latent digraph object of the graph.

call

the call made to this function.

activeFroms

list. If node i is solved then the ith index is a vector containing the nodes Y otherwise it is empty.

Zs

list. If node i is solved then the ith index is a vector containing the nodes Z otherwise it is empty.

Ls

list. If node i is solved then the ith index is a vector containing the nodes L otherwise it is empty.

References

Barber, R. F., Drton, M., Sturma, N., and Weihs L. (2022). Half-Trek Criterion for Identifiability of Latent Variable Models. Ann. Statist. 50(6):3174–3196. <doi:10.1214/22-AOS2221>.