rmcelreath / stat_rethinking_2022

Statistical Rethinking course winter 2022
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Slide 34 and 35 in Lecture 18 (Missing data) are cyclic graphs #23

Open djinnome opened 1 year ago

djinnome commented 1 year ago

I think it was an oversight, but on slides 34 and 35 in Lecture 18, there is an edge from $G^\ast\rightarrow M_g$. This has two problems:

  1. If the missingness mechanism is due to the fact that the species $G$ is less studied, then there should be an arrow from $G\rightarrow M_g$ instead of $G^\ast\rightarrow M_g$.
  2. The arrow from $G^\ast\rightarrow M_g$ and from $M_g\rightarrow G^\ast$ results in a cyclic graph, which breaks everything.

Hopefully, you can correct the slides and the video without having to change everything. I don't have access to the 2nd edition of the textbook, but I wonder if there is also an error in there.