Ggdag draw DAG and cause and effect diagram

Directed acyclic graph （DAG,Direct Acyclic Graph） It's a graph model . The graph consists of nodes and edges , Nodes represent variables , Edges represent some kind of connection between variables . If the edge between two nodes is clearly pointed , It's a directed graph . If a directed graph starts from a node , Cannot return to the original node through several edges , It's a directed acyclic graph . Bayesian network is a famous example of directed acyclic graph .

dagitty（ There is a corresponding R package , Also called dagitty） It is a powerful browser based causal model diagram analysis tool .ggdag Yes dagitty The package has made some extensions , Can create neat （tidy） Cause and effect directed acyclic graph .ggdag Based on ggplot2 and ggraph（ See network data visualization （3 Revised edition ）ggraph：ggplot2 Network visualization ） On the basis of , Can be in R Easier to draw in the environment DAG.

ggdag You can directly dagitty Package creation DAG Into neat data structures .

library(dagitty)
library(ggdag)

dag <- dagitty(