I want to discuss a nice series of figures used to teach relational join semantics in R for Data Science by Garrett Grolemund and Hadley Wickham, O’Reilly 2016. Below is an example from their book illustrating an inner join:
Please read on for my discussion of this diagram and teaching joins. Continue reading Visualizing relational joins
I am going to write about an insidious statistical, data analysis, and presentation fallacy I call “the zero bug” and the habits you need to cultivate to avoid it.
The zero bug
Here is the zero bug in a nutshell: common data aggregation tools often can not “count to zero” from examples, and this causes problems. Please read on for what this means, the consequences, and how to avoid the problem. Continue reading The Zero Bug