Instruct: Classify a review as either positive or negative.
Query: Ridiculously unnecessary

The only time this book helped me make money was when I sold it back on Amazon. Elliot is ridiculous. Just learn to respect how your own mind recognizes and interacts with price; then see about basing a system around that. If Elliot ends up being your religion then fine, but for most people this will just make you want to pour acid on your retinas.