Transforming Homo Economicus into Homo Ludens: a field experiment on gamification in a utilitarian peer-to-peer trading service Juho Hamari (corresponding author) juho.hamari@uta.fi, Tel.: +358 40 835 9563 School of Information Sciences, 33014 University of Tampere, Finland. Pre-print To cite: Hamari, J. (2013). Transforming Homo Economicus into Homo Ludens: A Field Experiment on Gamification in a Utilitarian Peer-To-Peer Trading Service. Electronic Commerce Research and Applications, 12 (4), 236-245. Abstract During recent years, the addition of game mechanics to non-game services has gained a relatively large amount of attention. Popular discussion connects ‘gamification’ to successful marketing and increased profitability through higher customer engagement, however there is a dearth of empirical studies that confirm such expectations. This paper reports the results of a field experiment, gamifying a utilitarian peer-to-peer trading service by implementing the game mechanic of ‘badges’ that users could earn from a variety of tasks. The users (N=3234) were randomly assigned to treatment groups and subjected to different versions of the badge system (a 2x2 design). Results show that the mere implementation of gamification mechanics does not automatically lead to significant increases in use activity in the studied utilitarian service, however those users who actively monitored their own badges and those of others in the study showed an increased user activity. Keywords: gamification; service marketing; social commerce; badges; achievements; game design; collaborative consumption