Visualizing Linear Models (Springer, 2021) - This short textbook introduces the theory of linear models, emphasizing two important and complementary ways of visualizing the concepts: the observations picture and the variables picture. Accompanying flash cards help reinforce the material.

Visualizing Random Variables - This will be a follow-up to Visualizing Linear Models that encourages the student to extend the two-pictures idea to random vectors more generally by understanding $$L^2$$ spaces using intuition from Euclidean space.

Data Analysis with R: The Big Picture - A gentle and systematic introduction for complete beginners. (Unfinished.)

A Systematic Guide to Mathematical Statistics - This is a long-term project, but early drafts of some sections are posted below.