Check conditions on query

Given an admissible causal DAG, check that given a causal query satisfies conditions that guarantee the corresponding causal problem to be a linear program. Throws error messages detailing any conditions violated.

Usage

querycheck(effecttext, graphres)

Arguments

effecttext

A string representing a causal query.

graphres

An igraph object representing a digraph.

Value

TRUE if effecttext is parsable, contains only variables in V(graphres) and satisfies conditions for linearity; else FALSE.

Examples

graphres <- graph_from_literal(X -+ Y, X -+ M, M -+ Y, Ul -+ X, Ur -+ M, Ur -+ Y)
V(graphres)$leftside <- c(1, 0, 0, 1, 0)
V(graphres)$latent <- c(0, 0, 0, 1, 1)
V(graphres)$nvals <- c(2, 2, 2, 2, 2)
V(graphres)$exposure <- c(0, 0, 0, 0, 0)
V(graphres)$outcome <- c(0, 0, 0, 0, 0)
E(graphres)$rlconnect <- c(0, 0, 0, 0, 0, 0)
E(graphres)$edge.monotone <- c(0, 0, 0, 0, 0, 0)
effecttext <- "p{Y(M(X = 0), X = 1) = 1} - p{Y(M(X = 0), X = 0) = 1}"
querycheck(effecttext = effecttext, graphres = graphres) # TRUE
#> [1] TRUE