New paper by Henry Sauermann and Chiara Franzoni: “Crowd-based knowledge production is attracting growing attention from scholars and practitioners. One key premise is that participants who have an intrinsic “interest” in a topic or activity are willing to expend effort at lower pay than in traditional employment relationships. However, it is not clear how strong and sustainable interest is as a source of motivation. We draw on research in psychology to discuss important static and dynamic features of interest and derive a number of research questions regarding interest-based effort in crowd-based projects. Among others, we consider the specific versus general nature of interest, highlight the potential role of matching between projects and individuals, and distinguish the intensity of interest at a point in time from the development and sustainability of interest over time. We then examine users’ participation patterns within and across 7 different crowd science projects that are hosted on a shared platform. Our results provide novel insights into contribution dynamics in crowd science projects. Moreover, given that extrinsic incentives such as pay, status, self-use, or career benefits are largely absent in these particular projects, the data also provide unique insights into the dynamics of interest-based motivation and into its potential as a driver of effort.”