Instruct: Classify Amazon reviews into positive or negative sentiment
Query: This book is useless.

Sachs' book is full of tables and impressive looking statistical methods. Unfortunately, the results of the statistical methods are not interpreted correctly. Just because somebody read a statistics textbook and learned how to do a chi-square test doesn't necessarily mean he can apply the methodology correctly. It's just as well this book's out of print. Buy a statistics textbook instead and learn some probability and statistical methodology. Forget about astrology.