I came across The Choose Yourself Guide To Wealth by James Altucher
Let's read the reviews. A lot of five-stars, so it must be good, right? Well, you wouldn't know by reading the reviews, because some of the reviews are useless, possibly the product of promotional campaign by the author to inflate the book's Amazon rankings and ratings.
Here are a list of reviews for the book, the most suspect ones denoted by a red 'x'
Or another one, in which scheme is revealed:
Apparently the author must have had a mailing list and sold the first batch of copies for 99 cents, requiring that the purchaser leave a good review. The result was a flood of low-quality 5-star reviews. Then the price was raised to $22 after the promotion ended.
The are some probably legitimate reviews among the sea of fake ones, but the problem is fake reviews are bad for readers, who buy the book on the expectation that these 'five-star' reviews are representative of those who actually read the book and liked it a lot, not people who were enticed into leaving a high rating for a discounted price. This is a fairly common practice on Amazon though, and it makes sense from an economic and psychological standpoint. If you sell a book for very little money (99 cents or so), the buyer is less likely be annoyed if the quality is poor and will actually feel indebted to the author for getting such a 'good' deal even if the content isn't very good, leaving a four or five-star review as way of repaying the author for his generosity. Then the herd/bandwagon effect kicks in as normal people buy the book based on the shill reviews, creating a feedback loop of more buyers and more reviews. It sucks for buyers, who get burned by the fake reviews, and for the authors who don't use shill marketing and get out-ranked by shill books, but I don't see this problem going away anytime soon, since Amazon publishing is a rapidly growing industry and thousands of authors, both good and bad, will look for any sort of 'edge' to stand-out among the masses of self-published books.
Tips for Book Buyers
1. Check the history of suspicious reviewers for low quality, vague reviews. Shills tend to review lots of products, leaving vague, useless reviews for all of them.
2. Very very suspicious of short, vague 1 and 5-star reviews.
3. Read the 2-3 star reviews. Those are the most likely to be authentic.
4. Check for any promotional language in the reviews, things like 'I got the book discounted...', or 'I was given a trial copy..' etc.
5. Read the comments under the reviews. You can glean important information that isn't otherwise contained in the review.
6. As a rule of thumb, trust longer, more-specific reviews over shorter ones.