Generating Equivalent Models — Equivalent DAGs and Classes • ggdag

Returns a set of complete partially directed acyclic graphs (CPDAGs) given an input DAG. CPDAGs are Markov equivalent to the input graph. See dagitty::equivalentDAGs() for details. node_equivalent_dags() returns a set of DAGs, while node_equivalent_class() tags reversable edges. ggdag_equivalent_dags() plots all equivalent DAGs, while ggdag_equivalent_class() plots all reversable edges as undirected.

Usage

node_equivalent_dags(
  .dag,
  n = 100,
  layout = ggdag_option("layout", "auto"),
  ...
)

ggdag_equivalent_dags(
  .tdy_dag,
  ...,
  size = 1,
  edge_type = c("link_arc", "link", "arc", "diagonal"),
  node_size = ggdag_option("node_size", 16),
  text_size = ggdag_option("text_size", 3.88),
  label_size = ggdag_option("label_size", text_size),
  text_col = ggdag_option("text_col", "white"),
  label_col = ggdag_option("label_col", "black"),
  edge_width = ggdag_option("edge_width", 0.6),
  edge_cap = ggdag_option("edge_cap", 8),
  arrow_length = ggdag_option("arrow_length", 5),
  use_edges = ggdag_option("use_edges", TRUE),
  use_nodes = ggdag_option("use_nodes", TRUE),
  use_stylized = ggdag_option("use_stylized", FALSE),
  use_text = ggdag_option("use_text", TRUE),
  use_labels = ggdag_option("use_labels", FALSE),
  label_geom = ggdag_option("label_geom", geom_dag_label_repel),
  unified_legend = TRUE,
  key_glyph = NULL,
  text = NULL,
  label = NULL,
  node = deprecated(),
  stylized = deprecated()
)

node_equivalent_class(.dag, layout = ggdag_option("layout", "auto"))

ggdag_equivalent_class(
  .tdy_dag,
  ...,
  size = 1,
  node_size = ggdag_option("node_size", 16),
  text_size = ggdag_option("text_size", 3.88),
  label_size = ggdag_option("label_size", text_size),
  text_col = ggdag_option("text_col", "white"),
  label_col = ggdag_option("label_col", "black"),
  edge_width = ggdag_option("edge_width", 0.6),
  edge_cap = ggdag_option("edge_cap", 8),
  arrow_length = ggdag_option("arrow_length", 5),
  use_edges = ggdag_option("use_edges", TRUE),
  use_nodes = ggdag_option("use_nodes", TRUE),
  use_stylized = ggdag_option("use_stylized", FALSE),
  use_text = ggdag_option("use_text", TRUE),
  use_labels = ggdag_option("use_labels", FALSE),
  label_geom = ggdag_option("label_geom", geom_dag_label_repel),
  unified_legend = TRUE,
  key_glyph = NULL,
  edge_engine = ggdag_option("edge_engine", "ggraph"),
  text = NULL,
  label = NULL,
  node = deprecated(),
  stylized = deprecated()
)

Arguments

.dag: input graph, an object of class tidy_dagitty or dagitty
n: maximal number of returned graphs.
layout: a layout available in ggraph. See ggraph::create_layout() for details. Alternatively, "time_ordered" will use time_ordered_coords() to algorithmically sort the graph by time. You can also pass the result of time_ordered_coords() directly: either the function returned when called with no arguments, or the coordinate tibble returned when called with arguments.
...: optional arguments passed to ggraph::create_layout()
.tdy_dag: A tidy_dagitty or dagitty object
size: A numeric value scaling the size of all elements in the DAG. This allows you to change the scale of the DAG without changing the proportions.
edge_type: The type of edge, one of "link_arc", "link", "arc", "diagonal".
node_size: The size of the nodes.
text_size: The size of the text.
label_size: The size of the labels.
text_col: The color of the text.
label_col: The color of the labels.
edge_width: The width of the edges.
edge_cap: The size of edge caps (the distance between the arrowheads and the node borders).
arrow_length: The length of arrows on edges.
use_edges: A logical value. Include a geom_dag_edges*() function? If TRUE, which is determined by edge_type.
use_nodes: A logical value. Include geom_dag_point()?
use_stylized: A logical value. Include geom_dag_node()?
use_text: A logical value. Include geom_dag_text()?
use_labels: A logical value. Include a label geom? The specific geom used is controlled by label_geom.
label_geom: A geom function to use for drawing labels when use_labels = TRUE. Default is geom_dag_label_repel. Other options include geom_dag_label, geom_dag_text_repel, geom_dag_label_repel2, and geom_dag_text_repel2.
unified_legend: A logical value. When TRUE and both use_edges and use_nodes are TRUE, creates a unified legend entry showing both nodes and edges in a single key, and hides the separate edge legend. This creates cleaner, more compact legends. Default is TRUE.
key_glyph: A function to use for drawing the legend key glyph for nodes. If NULL (the default), the glyph is chosen automatically based on the unified_legend setting. When provided, this overrides the automatic selection. Common options include draw_key_dag_point, draw_key_dag_combined, and draw_key_dag_collider.
text: The bare name of a column to use for geom_dag_text(). If use_text = TRUE, the default is to use name.
label: The bare name of a column to use for labels. If use_labels = TRUE, the default is to use label.
node: Deprecated.
stylized: Deprecated.
edge_engine: The engine used to draw edges. Either "ggraph" (default) or "ggarrow". When "ggarrow", edges are drawn using ggarrow geoms, which support additional customization via the arrow_head, arrow_fins, arrow_mid, and curvature global options (see ggdag_options_set()).

Value

a tidy_dagitty with at least one DAG, including a dag column to identify graph set for equivalent DAGs or a reversable column for equivalent classes, or a ggplot

Examples

g_ex <- dagify(y ~ x + z, x ~ z)

g_ex |> node_equivalent_class()
#> # DAG:
#> # A `dagitty` DAG with: 3 nodes and 3 edges
#> #
#> # Data:
#> # A tibble: 4 × 8
#>   name      x     y direction to     xend  yend reversable
#>   <chr> <dbl> <dbl> <fct>     <chr> <dbl> <dbl> <lgl>     
#> 1 x       0       2 ->        y       0.5     1 TRUE      
#> 2 y       0.5     1 NA        NA     NA      NA FALSE     
#> 3 z       0.5     3 ->        x       0       2 TRUE      
#> 4 z       0.5     3 ->        y       0.5     1 TRUE      
#> #
#> # ℹ Use `pull_dag() (`?pull_dag`)` to retrieve the DAG object and `pull_dag_data() (`?pull_dag_data`)` for the data frame

g_ex |> ggdag_equivalent_dags()