eBooks and book sales

There's been a long-running argument about whether making eBooks freely available without DRM or anything like that helps or hurts sales of physical copies of the book. The DRM proponents have usually argued that the people saying freely-available eBooks help sales are depending entirely on anecdotes that don't prove anything. Well, end of that argument. A pair of graduate students at the University of Michigan did a detailed study of 41 titles that were released as eBooks, looking at their sales figures pre- and post-eBook release. In most cases, an eBook release meant increased post-release sales of the books. The exception was Tor's release, which dramatically demonstrates the problems with restrictive eBook releases. Tor made the eBook versions available for only one week, required registration before you could download and generally made it annoying to get the eBook version. This group of books suffered a significant drop in sales, while the other 3 groups studied showed significant increases in sales.

Publishers take note.