An Amaz-ing discovery

On the day we announced the Cybils finalists, Jen Robinson called on everyone to buy copies of the winners from Amazon, while Sheila Ruth charted whether the books rose in popularity.

Did we make a difference? Can we add "marketplace clout" to our list of accomplishments?

The answer is a qualified yes. We affected the sales rankings, sometimes dramatically, for some titles.

We pasted in the charts after the jump for you, but first a few words from Sheila about how to read the charts, since the lines sink instead of rise, which to Amazon is a good thing: assigns a sales rank to each book, which reflects its relative popularity. Think of it as a giant bestseller list that  includes every book on The most popular book at any given  time has the coveted sales rank of 1, meaning that it’s the #1 book. The second most popular book has a sales rank of 2, and so on down to  the poor, unpopular books that have a sales rank of a couple million. So, the lower the number, the better the rank. Sales ranks  are updated every hour to reflect the sales for that hour.

In actuality, the algorithm Amazon uses isn’t quite that  straightforward, but it’s helpful to think of it in this way. And it  helps to understand when you view the charts that when the line goes down, sales are going up.

Anyone interested in more technical details about Amazon’s sales rank  may want to read this article.

Note: Windows Explorer may scrunch up this text due to some weird coding. After you click on the continued post below, hit your refresh button and the text should realign correctly.


Click on each image to see a full-sized graph. Where the numbers plummet is when sales started taking off.