"Count what is countable. Measure what is measureable. What is not measureable, make measureable." -- Galileo

Saturday, November 19, 2011

"Quarterly" Amazon Stats

I'm at bit tardy on my Amazon sales rank summary -- should've had one out in August.  No matter, here's the graph.  Remember that with sales rank, lower values are better.

In general all Plone books are trending upwards, which is not unexpected considering that the Plone 3 titles are being replaced by Plone 4 ones.  Martin Aspeli's Professional Plone 4 Development tops the chart so to speak with a sales rank of 156K with de Alba close behind.  Plone Live once again is in the basement (at the top of the chart), but that is more likely due to its heavy reliance on non-Amazon sales channels. 

The table of the current titles and their sales ranks are given in the table below.  Of interest this time is the column on sales/yr.  I found a graph that illustrated the approximate Amazon sales rank function, which turns out to be a power law.  A little regression with Open Office Calc gave me an equation of
f(x) = (1.3*10^6) * (x^-1.1)
This equation has numerous potentially huge sources of error, but I thought it would be interesting to toss it out and let the authors themselves reflect on the results.  Please note that these are Amazon-only numbers.  Because most titles are published by Packt, this almost certainly is a small fraction of total sales. 

Amazon Page Rank Stats November 2011

Title Author Sales rank Sales/yr Rating
Professional Plone 4 Development Aspeli 156,335 150 4.50
Plone 3 Intranets de Alba 192,392 120 4.00
Plone 3 Theming Williams 704,159 29 5.00
Professional Plone Development: Plone 3 Aspeli 692,760 30 4.67
A User's Guide to Plone 4 Nagle et al. 755,217 27 n/a
The Definitive Guide to Plone (2nd ed) Delmonte, et al. 984,891 20 1.00
Building Websites with Plone Cooper 1,050,568 19 3.71
Plone 3 Products Development Cookbook Giménez & Romero 1,270,629 15 4.00
Practical Plone 3 Knox et al. 1,025,403 19 4.80
The Definitive Guide to Plone (1st ed) McKay 1,239,686 16 4.14
Plone 3 for Education Rose 1,722,143 11 4.00
A User's Guide to Plone: Updated for Plone 3 Lotze & Nagle 1,773,374 11 3.00
Plone Content Management Essentials Meloni 1,801,775 10 3.11
Content Management with Plone: Handbook Lotze& Theune 1,954,272 10 n/a
Plone 3 Multimedia Gross 2,833,640 6 3.67
Plone Live Pelletier 2,886,475 6 4.80

I'd like to find out what actual sales numbers are directly from authors, but only if you don't consider it SBI, "sensitive business information".