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Classify DAG nodes

Source: R/classify.R
classify_nodes.Rd

Labels each node by causal role in a console tabular grid. This function is mostly used as an internal helper, but can be used on its own. Users are encouraged to alternatively use DAGassist::DAGassist(show=roles) for role table specific output.

Usage

classify_nodes(dag, exposure, outcome)

Arguments

dag

A dagitty DAG object.

exposure

Optional– inferred from DAG if not set; character; exposure node name (Exp.).

outcome

Optional– inferred from DAG if not set; character; outcome node name (Out.).

Value

A data.frame with one row per node and columns:

  • variable (node name)

  • logical flags: is_exposure, is_outcome, is_confounder, is_mediator, is_collider, is_neutral_on_treatment, is_neutral_on_outcome, is_descendant_of_mediator, is_descendant_of_collider, is_descendant_of_confounder_on_bdp, is_descendant_of_confounder_off_bdp

  • role (a single primary label)

Note

Roles legend: Exp. = exposure Out. = outcome CON = confounder MED = mediator COL = collider dOut = descendant of Out. dMed = descendant of any mediator, dCol = descendant of any collider dConfOn = descendant of a confounder on a back-door path dConfOff = descendant of a confounder off a back-door path NCT = neutral control on treatment NCO = neutral control on outcome

Examples

  d1 <- dagitty::dagitty("dag {X[exposure];Y[outcome] Z -> X; Z -> Y; X -> Y }") 
  classify_nodes(d1)
#> variable  role        Exp.  Out.  conf  med  col  dOut  dMed  dCol  dConfOn  dConfOff  NCT  NCO
#> X         exposure    x                                                                        
#> Y         outcome           x                                                                  
#> Z         confounder              x