Seven (weak and strong) helping effects systematically tested in separate evaluation, joint evaluation and forced choice

In ten studies (N = 9187), I systematically investigated the direction and size of seven helping effects (the identifiable-victim effect, proportion dominance effect, ingroup effect, existence effect, innocence effect, age effect and gender effect). All effects were tested in three decision modes (separate evaluation, joint evaluation and forced choice), and in their weak form (equal efficiency), or strong form (unequal efficiency). Participants read about one, or two, medical help projects and rated the attractiveness of and allocated resources to the project/projects, or choose which project to implement. The results show that the included help-situation attributes vary in their: (1) Evaluability – e.g., rescue proportion is the easiest to evaluate in separate evaluation. (2) Justifiability – e.g., people prefer to save fewer lives now rather than more lives in the future, but not fewer identified lives rather than more statistical lives. (3) Prominence – e.g., people express a preference to help females, but only when forced to choose.