10.4 Using this book

A last word on how to use what precedes.

Read the chapters in order once, because they are built that way: the assumptions of chapters three to five make sense only against the model of chapter two, and the bias variance trade-off of chapter eight explains, after the fact, half of what was done in chapters six and seven.

Then use it as a reference, in the opposite direction. Begin with the question, use the table above to find the family of methods, and read the corresponding section with the data in front of you. Every piece of code in this book runs on both languages and on data that are either simulated in the text or distributed with it, so any example can be modified and re-executed.

And when a result seems too good, look at it again. The most useful habit this book can leave is the one it has applied to itself throughout: check the number against the claim, and believe the number.