When being asked for help, people sometimes can only offer part of what is requested (i.e., partial help). The present research investigates whether helpers can accurately forecast how much help-seekers appreciate this understudied form of assistance. From multiple helping scenarios and a face-to-face interaction, we demonstrate an asymmetry in helpers' and help-seeker's appraisals of partial help: Helpers anticipated less appreciation for partial help than help-seekers felt in receiving it. This asymmetry arose from helpers' greater valuation of helping outcomes over intentions to be helpful than help-seekers'. Accordingly, when helpers' intentions were discounted, this asymmetry no longer persisted. Another account-helpers feel worse for breaking norms of helping than help-seekers-was not supported. We discuss several directions for future research on the psychology of partial prosocial behaviors.
Keywords: help-seeking; helping; prosocial behavior; social prediction.