For some data.table users, “dot-SD” is a bit of a mystery. But data.table creator Matt Dowle told me that it’s actually quite simple: Just think of it as a symbol representing “each group.” Let’s go ...

The table below shows my favorite go-to R packages for data import, wrangling, visualization and analysis — plus a few miscellaneous tasks tossed in. The package names in the table are clickable if ...

Before you can analyze and visualize data, you have to get that data into R. There are various ways to do this, depending on how your data is formatted and where it’s located. Usually, the function ...