Reader question — The five tests that cover most questions

Reader question on The five tests that cover most questions, and the answer belongs somewhere more findable than an email.

Hypothesis testing is taught as a zoo of named procedures. In practice a small number cover nearly everything, and choosing correctly is easier than remembering the zoo.

The question was, roughly, "when does this stop applying?" — which is the right question and the one lessons routinely fail to answer. Every technique has a range of validity, and stating it is what separates a lesson from a recipe.

It sits in the Statistics you will actually use module. The exercise is a thinking one rather than a query one — some of this material is about deciding what to compute, and that does not need a keyboard.

Ordering matters here more than in most courses. It follows Uncertainty, sampling, and how much to trust a number and leads into Correlation, confounding, and Simpson's paradox, and reading it out of sequence mostly works but costs you the setup.

Free means free, and it also means we can rewrite it whenever it is wrong. No edition, no errata PDF, nothing to repurchase. The whole course is 36 lessons and the fixes land the day we find them.