A little less than a year ago, I blogged on ebook giveaway experiments by major publishers (including Tor, Random House, and St. Martin's Press), and the question of whether such giveaways could boost print sales. At the time of my blog post, what reports there were (from both industry sources and individual authors) indicated that sales could indeed benefit.
Now someone is trying to quantify that information. Bloggasm reports that a doctoral student, John Hilton, is collecting data on the sales impact of ebook giveaways. He has identified approximately 40 titles for which a free e-version was released after the p-version was published, and tracked Bookscan numbers for eight weeks on both sides of the e-release.
Results so far are interesting. While four of the five Random House books Hilton identified showed an uptick in sales post-e-version, 20 of 24 Tor titles showed a decrease. Why the difference? "One possible explanation is that by making the free books available for only one week a different dynamic was present [for Tor] than when the books were made permanently available [by Random House]," Hilton says. "The opportunity for word-of-mouth to spread about the free book may have been significantly diminished in the model used by Tor."
Ultimately, as Bloggasm notes, "These are all unknowns, and these unknowns leave enough wiggle room so that proponents of both sides of the argument have plenty of leeway to argue why releasing a book for free — whether it’s through a Creative Commons license or Google Books — has a net benefit or detriment to sales."
Hilton's study is continuing, and presumably more information will be forthcoming.