En tout cas ceci:
The Short-Term Influence of Free Digital Versions of Books on Print Sales
publié par le Journal of Electronic Publishing a procédé à quelques tests grandeur nature.
Dans les genres qui nous intéressent, voici ce qu'ils trouvent:
On March 4, 2009, Random House announced that it was releasing free digital versions of five science fiction/fantasy books. These books are:
Assassin’s Apprentice (Robin Hobb)
His Majesty’s Dragon (Naomi Novik)
Blood Engines (T.A. Pratt)
Red Mars (Kim Stanley Robinson)
Settling Accounts: Return Engagement (Harry Turtledove)
Table 3: Sales of Random House Titles
Col 1: Book
Col 2: sales 8 weeks before free digital release
Col 3: Books sales 8 weeks following free digital release
Col 4: Net difference (post sales–pre sales)
Books
Title 1 316 252 –64
Title 2 1812 2153 341
Title 3 1612 1677 65
Title 4 413 508 95
Title 4 796 817 21
Total 4949 5407 458
En gros 10% d'augmentation (à la louche). D'autres tableaux pour les publication Tor montrent plutôt une baisse, les auteurs tentant d'expliqur cela par la mise enligne seulement durant une semaine avec enregistrement requis.
En résumé, ils trouvent un impact moyenné positif dans les 5%, sans trop se mouiller.
The results of the present study must be viewed with caution. Although the authors believe that free digital book distribution tends to increase print sales, this is not a universal law. The results we found cannot necessarily be generalized to other books, nor be construed to suggest causation. The timing of a free e-book’s release, the promotion it received and other factors cannot be fully accounted for. Nevertheless, we believe that this data indicates that when free e-books are offered for a relatively long period of time, without requiring registration, print sales will increase.
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Future studies might examine relationships between the potential audience for a book and the impact of free digital distribution.
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In addition, we did not study how free books affect the sales of other titles by an author.
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The explosive growth of Kindle and other e-book formats could dramatically impact how free distribution affects for-profit sales and even alter the relative importance of print sales. As the electronic publishing industry matures it will be increasingly important to research the effects of free distribution of electronic books.
Ben tiens :-)