The valuation of unprotected works: a case study of public domain photographs on Wikipedia

Heald, P., Erickson, K. and Kretschmer, M. (2015) The valuation of unprotected works: a case study of public domain photographs on Wikipedia. Harvard Journal of Law and Technology, 29(1), pp. 1-32.

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What is the value of works in the public domain? We study the biographical Wikipedia pages of a large data set of authors, composers, and lyricists to determine whether the public domain status of available images leads to a higher rate of inclusion of illustrated supplementary material and whether such inclusion increases visitorship to individual pages. We attempt to objectively place a value on the body of public domain photographs and illustrations which are used in this global resource. We find that the most historically remote subjects are more likely to have images on their web pages because their biographical life-spans pre-date the existence of in-copyright imagery. We find that the large majority of photos and illustrations used on subject pages were obtained from the public domain, and we estimate their value in terms of costs saved to Wikipedia page builders and in terms of increased traffic corresponding to the inclusion of an image. Then, extrapolating from the characteristics of a random sample of a further 300 Wikipedia pages, we estimate a total value of public domain photographs on Wikipedia of between $246 to $270 million dollars per year.

Item Type:Articles
Keywords:Wikipedia, public domain, copyright, Creative Commons, peer production, valuation, photography, digital images
Glasgow Author(s) Enlighten ID:Erickson, Professor Kristofer and Kretschmer, Professor Martin
Authors: Heald, P., Erickson, K., and Kretschmer, M.
Subjects:H Social Sciences > HB Economic Theory
K Law > K Law (General)
College/School:College of Social Sciences > School of Law
Journal Name:Harvard Journal of Law and Technology
Publisher:Harvard Law School
ISSN (Online):2153-263X
Copyright Holders:Copyright © 2015 Harvard Law School
First Published:First published in Harvard Journal of Law and Technology 29(1):1-32
Publisher Policy:Reproduced in accordance with the copyright policy of the publisher

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Project CodeAward NoProject NamePrincipal InvestigatorFunder's NameFunder RefLead Dept
621241The Value of Public Domain Works: Collaboration and Knowledge Exchange to Develop Policies for the Commercial Use of Public Domain WorksMartin KretschmerEconomic & Social Research Council (ESRC)ES/K008137/1SCHOOL OF LAW