Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Was that a point that just rolled across the floor?

Absolutely attrocious. After making the very solid points of buying stock in companies that have a high return on capital and a high return on investment. Then Greenblatt drones on and on. In the end, the book gives a mechanical trading system that uses absolutely no refinement. The system would have you trading in BB and OB stocks that don't event have revenues! Come on Prof G! Give us something that has some thought to it....not just a model that worked. And, OBTW, he never "future tested" the model. DON'T WASTE YOUR MONEY. This book is of no consequence to readers who are interested in investing shrewdly.