  Crowd employment is a new form of short-term and flexible employment which
has emerged during the past decade. In order to understand this new form of
employment, it is crucial to illuminate the underlying motivations of the
workforce involved in it. This paper introduces the Multidimensional
Crowdworker Motivation Scale (MCMS), a scale for measuring the motivation of
crowdworkers on micro-task platforms. The MCMS is theoretically grounded in
self-determination theory and tailored specifically to the context of paid
crowdsourced micro-labor. The scale measures the motivation of crowdworkers
along six motivational dimensions, ranging from amotivation to intrinsic
motivation. We validated the MCMS on data collected in ten countries and three
income groups. Factor analyses demonstrated that the MCMS's six dimensions
showed good model fit, validity, and reliability. Furthermore, our measurement
invariance tests showed that motivations measured with the MCMS are comparable
across countries and income groups, and we present a first cross-country
comparison of crowdworker motivations. This work constitutes an important first
step towards understanding the motivations of the international crowd
workforce.
