all([]) is True and any([]) is False, and that’s the only sensible choice.

A cautionary tale of data analysis, chasing the ghosts of mean reversion, and the protective power of testing asymmetric effects.

The splitting fields of $x^5 - 7$ and $x^4 - 5$ both contain $\sqrt{5}$. This makes computing the Galois group of their product pretty interesting.

In a reckless spirit, we evaluate a tricky limit of integrals without the Lebesgue convergence theorems.

Textbook exercises compute eigenvalues from roots of the characteristic polynomial. What computers do is much neater.

An uncommon view of ridge regression, with proof and simulation.

Basis expansions allow linear regressions to fit non-linear relationships. We compare several common basis expansions, and advocate for linear and natural cubic splines.

A picture proof that AUC is the probability a randomly chosen positive example is scored above a randomly chosen negative one.

What happens when you call lm in R? At the bottom is some of the oldest open source code still in use.

How to write a Python module in C.