Perceived Utility (not Sympathy) Mediates the Proportion Dominance Effect in Helping Decisions

Research output: Contribution to journalArticle


The proportion dominance effect (PDE) refers to a higher motivation to help when the victims are part of a small (you can help 56 out of 60) rather than a large (you can help 56 out of 560) reference group. In two studies using different experimental paradigms, we investigated possible mediators of the PDE. Study 1 (N = 168) was conducted in three separate steps in order to test each link of the mediator model independently. Students read six vignettes where it was possible to help a fixed number of victims but where the size of the reference group was either small or large. When the reference group was small, helping motivation and perceived utility were higher, whereas sympathy towards the victims and perceived rights were not. A within-subject mediation analysis showed that perceived utility mediated the PDE. Study 2 (N = 36) presented four versions of a single helping-situation in a joint evaluation mode where the size of the reference group got gradually smaller in each version. All participants compared and responded to each version. Helping motivation increased as the reference group got smaller, and this effect was mediated by perceived utility rather than by distress, sympathy or perceived responsibilities. Our results suggest that unlike e.g. the identifiability and singularity effects, which have been suggested to be mediated by emotional reactions, the PDE is mediated by perceived utility.


Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Psychology


  • helping motivation, identifiable victim effect, perceived utility, proportion dominance effect, sympathy
Original languageEnglish
Pages (from-to)37-47
JournalJournal of Behavioral Decision Making
Issue number1
Publication statusPublished - 2014
Publication categoryResearch