First, disclaimers: Since the algorithm Amazon uses to generate its sales ranking is proprietary, the tests listed here are extrapolated from research and field work. Consensus is the Amazon system to provide marginal sales data at best.

For Pentecost, read Amazon's own definition of its system, slightly paraphrased from their FAQ: "The ranking system shows how sales of books are sold. The higher the number, the higher sales. The calculation is based on sales and updated every hour to reflect recent and historical sales of every item sold. We hope you find the Amazon. COM Sales Rank interesting! "This last sentence seems to indicate own views on the importance of sales rankings Amazon has to be seen.

No need to find the sales rank informative or helpful. You are supposed to interest you.

Currently, the process is more complicated than we understand. Only 10,000 books are updated every hour and the classification does not depend on the actual number of books sold, but rather on a comparison with sales figures of the 9999 other books in that same hour. At the same time, a trend calculation is applied to obtain a computerized sales trajectory. So, hypothetically, a book containing a classification of 2000 at 2pm and 3000 at 3 am, could hold a classification in 4000 4pm, but actually sold more books between 3-4 it did between 2-3.

Books with rankings between 10,000 and 100,000 are recalculated once a day instead of once per hour. Current projections, as well as historic sales information play a key role in these calculations. In fact, the predictive power of the Amazon ranking system is what allows a book recently published for a senior title established, although the actual figures for the latter outweighs the former.

Classification of books with more than 100,000 are also recalculated every day and applied with historical information and sales projections, although in the case of these books, history takes a backseat. Sales projections and the trend to play an active role in this area, so the scope of a book you can go from 900,000 to 200,000 in the space of 24 hours or less. Does this mean that the book has sold 700,000 copies in 24 hours? Absolutely not! What this means is that recent activity (ie purchases) for the book is likely higher than the 700,000 books that have been overcome. But do not get excited yet, since the activity of the 700,000 other books range from slow to stagnant, one or two orders are sufficient to propel a classification.

If you break the rank of a book in the Top 100,000, the calculation of sales history begins to raise his head, so a "phenomenon" book has a hard time maintaining a high ranking legitimate. A phenomenon that is defined by a book that leaps from the top hundreds of thousands in the lower thousands (or more) in the space of 24 hours or less, usually due to some concentrated marketing initiatives. Since the history of Amazon's sales so that the title is not compatible with the jump, the peak occurs then falls rapidly.

How all this translates into actual numbers?

Since the data are updated every hour or every day (depending on the current classification of a book), it is impossible to get cumulative sales figures, despite the application of these figures in the algorithm in the calculation. No, very hard at the idea that the actual number of books sold, the sales rank should be dissected dynamically, with the same immediacy as the ranking is calculated, (hourly for a maximum of 10,000 pounds or daily for Top 100,000 pounds). League table of a book cover 10.000 per hour for 24 hours and divide by 24 to reach your daily average range. In the case of a book Top 100,000, which makes their classification of each day for 7 days and divide by 7 to reach their average weekly rankings.

Note that this next piece of information is extremely arbitrary, based on sales staff or sales comparisons and data received from third party sources. In other words, is probably completely false. But rather than give up at this table until the cows come home, I will say this: it is difficult to give meaning to something that has no meaning. But it sure is interesting, and now, perhaps even somewhat useful.

If the average ranking of this book is: 2,000,000 + Perhaps a single / consignment inventory has been ordered.

1,000,000 + Current trends indicate that total sales will likely be less than 40 years.

100,000 + current trends indicate that total sales are likely to be below 200.

10,000 + copies estimated between 1 and 10 have been sold per week.

1,000 + estimated 10 100 copies have been sold per week.

Copies 100 + estimated between 100 and 200 have been sold per week.

10 + 200 to 1,000 copies sold per week.

Under 10 Estimate over 1,000 copies per week