UPDATE 2018-12-11 - I’m talking about the package DPLYR, not PURRR, as I had mistakenly written. There are many approaches for what is called the “split-apply-combine” approach (see this paper by Hadley Wickham). I recently thought about the best approach to use split-apply-combine approaches in R (see tweet, and this post). And I retweeted some criticism on the “present era” tidyverse approach (see this tweet), and check out the mentioned post by …