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Query D-connection

Source: R/query_functions.R
query_dconnected.Rd

Test whether sets of variables are d-connected in a DAG given a conditioning set. This is the complement of d-separation.

Usage

query_dconnected(.tdy_dag, from, to, conditioned_on = NULL)

Arguments

.tdy_dag

A tidy DAG object.

from

Character vector of nodes or a list of node sets.

to

Character vector of nodes or a list of node sets.

conditioned_on

Character vector of conditioning variables.

Value

A tibble with columns:

  • from_set: String representation of source nodes

  • from: List column of source nodes

  • to_set: String representation of target nodes

  • to: List column of target nodes

  • conditioning_set: String representation of conditioning variables

  • conditioned_on: List column of conditioning variables

  • dconnected: Logical indicating d-connection

Examples

library(ggdag)
dag <- dagify(
  y ~ x + z,
  x ~ w,
  z ~ w
)

query_dconnected(dag, from = "x", to = "z")
#> # A tibble: 1 × 7
#>   from_set from      to_set to        conditioning_set conditioned_on dconnected
#>   <chr>    <list>    <chr>  <list>    <chr>            <list>         <lgl>     
#> 1 {x}      <chr [1]> {z}    <chr [1]> {}               <chr [0]>      TRUE      
query_dconnected(dag, from = "x", to = "z", conditioned_on = "w")
#> # A tibble: 1 × 7
#>   from_set from      to_set to        conditioning_set conditioned_on dconnected
#>   <chr>    <list>    <chr>  <list>    <chr>            <list>         <lgl>     
#> 1 {x}      <chr [1]> {z}    <chr [1]> {w}              <chr [1]>      FALSE