Who this book is for
This book is for programmers or data scientists who are familiar with Clojure and want to use it in their data analysis processes. This isn't a tutorial on Clojure—there are already a number of excellent introductory books out there—so you'll need to be familiar with the language, but you don't need to be an expert.
Likewise, you don't have to be an expert on data analysis, although you should probably be familiar with its tasks, processes, and techniques. While you might be able to glean enough from these recipes to get started with, for it to be truly effective, you'll want to get a more thorough introduction to this field.