Game of Brainstorm : The Impact of a Badge System on Knowledge Sharing

Knowledge-sharing platforms have widely adopted gamification to encourage users to contribute high-quality content. Yet, the literature has not systematically studied the relationship between gamification and knowledge sharing. This research thus carefully evaluates the impact of a badge system regarding the volume (the number of badges), variety (the number of badge categories), and valence (the level of badges), along with the moderating effect of user membership tenure. To characterize the dynamics of user-system interactions on Stack Overflow, we specify a structural hidden Markov model (HMM) to quantify users’ corresponding knowledge contributions and engagement-state transitions. We show that the badge system encourages knowledge contributions with a more substantial impact on quality than quantity. Such impacts vary across the four identified engagement states: inactive, gentle, active, and vigorous. Specifically, high badge volume and valence help keep users staying or moving up to higher engagement states, whereas wide badge variety discourages active users from sharing knowledge. We also notice that user membership tenure moderates the impacts of badges heterogeneously. Besides, we leverage the individual parameters of HMM to conduct counterfactual analyses to fine-tune badge-awarding policies. This study provides new aspects to contribute to the gamification and knowledge-sharing literature and generates actionable implications for platforms and gamification-system designers