Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Unclear and not helpful

This book is not at all helpful, it is hard to follow, and problems are hard to understand without diagrams. Sometimes you're stuck on one paragraph for an hour, because you're unable to see how the author got some equation, and he isn't the least bit interested in giving readers a hint. There are also a couple of bad mistakes in problem sections, asking students to prove incorrect statements, or omitting assumptions that should've been stated. This book will confuse you more than it'll help you.