Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Waste of time and money

Far too basic, primitive and irrelevant to be useful for anybody trying to understand the stock market. Do not even get close to the today's stock market with the book. No PRACTICAL value at all. Go for "How to Make Money in Stocks" by W.J.O'Neil - a far superior practical guide to what, when and how in the stock market.