Effortful, burdensome — three unipolar items rate how much of a hassle referring someone else feels like.
7-point unipolar Likert (1=strongly disagree, 7=strongly agree)
Gershon, R., Cryder, C., & John, L.K. (2020). Why Prosocial Referral Incentives Work: The Interplay of Reputational Benefits and Action Costs. Journal of Marketing Research, 57(1), 156–172.
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