Given reviews from Amazon, classify those review based on their content into two classes: Negative or Positive.
One example: I've read this book with much expectation, it was very boring all through out the book
Solution is here: Negative
Explanation: Review writer does not like the book because it was boring, therefore it is a negative review.

Now, solve this: The author is funded by the big industries which explains the selection of certain topics and the huge bias it reflects. No matter how many good reviews and bibliographic citations appear here, the ideas expressed reflect corporate interests and not scientific knowledge. Always look at the source!! Research very well where this people's funds come from and that will tell you a little bit more about the real issues.
Solution:
Negative