Manipulation of Amazon Sales Rank

Written By: Timothy Fish Published: 7/25/2007

A short time ago, I wrote an article about how the sales rank on Amazon.com is calculated. Amazon is very closed lipped about the exact details of how it is done, but my article provides the outline of a system that would work very similarly to the way Amazon.com sales rank works. One of the things that my original article did not address is how Amazon.com prevents manipulation of sales rank.

Unlike Google page rank, there is very few ways that book sellers can manipulate Amazon sales rank to make products appear to be selling better than they really are. Amazon determines sales rank by the number of books that they sell, so purchasing books is the only way to manipulate sales rank.

One thing that a potential sales rank manipulator might be temped to try is to place a large order for books. An author or a publisher has ways of getting most or all of the money back from any books he buys, so it is not out of the question that he might purchase several hundred books in hopes of positioning his book as a best seller. Amazon has put things in place to prevent this practice. When a customer places an order for more than one copy of the same book, Amazon records this as a single sale. The sales rank will decrease, but it will not reflect the total number of books in an order.

Since sellers cannot manipulate sales rank with large single orders for the book, one might think that the thing to do is to place several orders for the same book. Amazon has taken steps to prevent this as well. It appears that only the first book counts for any customer.

The steps that Amazon has taken to prevent the manipulation of sales rank are both good and bad. They are good because authors and publishers are unable to improve the rank of a book by purchasing copies that they will be destroy or resell through Amazon.com. The bad side of it is that return customers who are purchasing more copies of the book because they think their friends should read it are not reflected in the sales rank. In the first month of sales of Searching for Mom I have at least eleven books that people purchased from Amazon.com and they did not include these sales in the sales rank for the book.

I do not know how many more books I will sell to repeat customers, but there are some books that are sold as multiple copies to a single customer by their very nature. Bible study books are one example. The leader of a Bible study group may order five, ten, twenty or more books at one time rather than asking the members of the group to go out and purchase their own copy. These books may appear to be selling in lower numbers than what they really are. I think that the thing we need to take from this is that Amazon sales rank is not completely accurate and we must be careful about placing too much importance on it, while at the same time we can be fairly confident that it is not being manipulated by the people selling products.