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Query Markov Blanket

Source: R/query_functions.R
query_markov_blanket.Rd

Find the Markov blanket for specified variables in a DAG. The Markov blanket includes parents, children, and parents of children (co-parents).

Usage

query_markov_blanket(.tdy_dag, .var = NULL)

Arguments

.tdy_dag

A tidy_dagitty or dagitty object

.var

Character vector of variables to query. If NULL, returns parents for all nodes.

Value

A tibble with columns:

  • node: The node

  • blanket: String representation of Markov blanket nodes

  • blanket_vars: List column containing Markov blanket nodes

  • blanket_size: Size of the Markov blanket

Examples

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

query_markov_blanket(dag)
#> # A tibble: 4 × 4
#>   node  blanket   blanket_vars blanket_size
#>   <chr> <chr>     <list>              <int>
#> 1 w     {x, z}    <chr [2]>               2
#> 2 x     {w, y, z} <chr [3]>               3
#> 3 y     {x, z}    <chr [2]>               2
#> 4 z     {w, x, y} <chr [3]>               3
query_markov_blanket(dag, .var = "x")
#> # A tibble: 1 × 4
#>   node  blanket   blanket_vars blanket_size
#>   <chr> <chr>     <list>              <int>
#> 1 x     {w, y, z} <chr [3]>               3