title: Figures with boxes, arrows etc. in Markdown
body: <p>I am interested in displaying a causal mechanism visually with some plain boxes/circles connected by arrows in my paper written in RMarkdown. Something like this: </p>
  
  <p><a href="https://i.stack.imgur.com/9E3fw.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/9E3fw.png" alt="Found on Google"></a></p>
  
  <p>How is this done in RMarkdown? Would you recommend me to create a picture in a another app and import to RMarkdown like a picture? </p>