Why Open Source?
In a nutshell, because I did not write my book for money but for fun. So, once the deed is done, the cost is sunk and the only sensible course of action is to maximize diffusion through open-sourcing.
I started assembling my handwritten IO lecture notes in Napoli a decade ago. As I kept adding more material, I also developed LaTeX skills to typeset them into a fine-looking document.
In 2005, I proposed my book to several renowned academic publishers. Although two dozens reviewers approved the aims and scope of my project, they felt necessary a serious proof reading; many also called for a revision of style and level to ensure that the book could compete successfully in the market for undergraduates. The limited amount of time I could dedicate to these tasks would have delayed publication. I therefore decided to address a maximum of concerns during 2006 and go for self-publishing (cf. ISBN) with the online printing service of Lulu. The resulting textbook was near complete as regards contents but still an advanced draft in terms of penmanship. To compensate buyers for these deficiencies, I chose to price it at printing cost (≈11€) and sold the ebook at the same price. Although I assembled a massive 20k+ email distribution list to publicize my effort, I came short of moving a hundred copies (but close). I realized that only a major house could ask a positive price for the work of an unknown author.
Over the last years, I have been revising bits and pieces and also adding new material as I saw fit. As a consequence, I discontinued online selling, all the more so because I entered into advanced discussions with a new publisher to issue a monograph. I got the contract in my hands but never signed it, feeling that losing my intellectual property rights over so much investment wasn’t worth the while. Indeed, already in my forties, I’m just a foot soldier in academia. I cannot realistically hope to generate much endorsement or praise which is a necessary condition to make a decent financial return on my work. With respect to academic achievement, a textbook publication record is a small feat that will not add much to my CV.
Being an economist, I weighted the pros and cons of my two available publishing choices. On the one hand, if I go with the contract, success is an &epsilon probability event associated to a minimal utility payoff. On the other hand, if I go open-source, success is a 2ε probability event associated to a larger utility payoff as I care more about recognition than royalties. Quite simply then, open-source is the optimal decision. It will further the diffusion of knowledge and allow me to improve further my book thanks to readers’ feedback. The general case for open-sourcing academic textbooks is best made by David Levine and Preston McAfee; see also Martin Osborne page on prices.
P.S. Preston McAfee is, as far as I know, the first author of an open-source textbook in economics. In defense of my novelty claim, only his 2006 version is truly open-source while the current one is not open-source anymore. Lastly, I have to mention IOSA by Church & Ware whose digital version is available for free.