quality:correction
Amazon sales rank

The Amazon sales rank (ASR) indicates the popularity of a product sold on any Amazon locale. It is a relative indicator of popularity that is updated hourly. Effectively, it is a "best sellers list" for the millions of products stocked by Amazon. While the ASR has no direct effect on the sales of a product, it is used by Amazon to determine which products to include in its bestsellers lists. Products that appear in these lists enjoy additional exposure on the Amazon website and this may lead to an increase in sales. In particular, products that experience large jumps (up or down) in their sales ranks may be included within Amazon's lists of "movers and shakers"; such a listing provides additional exposure that might lead to an increase in sales. For competitive reasons, Amazon does not release actual sales figures to the public. However, Amazon has now begun to release point of sale data via the Nielsen BookScan service to verified authors. While the ASR has been the source of much speculation by publishers, manufacturers, and marketers, Amazon itself does not release the details of its sales rank calculation algorithm. Some companies have analyzed Amazon sales data to generate sales estimates based on the ASR, though Amazon states:

Please keep in mind that our sales rank figures are simply meant to be a guide of general interest for the customer and not definitive sales information for publishers—we assume you have this information regularly from your distribution sources