The identifiable victim effect refers to the tendency of individuals to offer greater aid when a specific, identifiable person ("victim") is observed under hardship, as compared to a large, vaguely defined group with the same need. The effect is also observed when subjects administer punishment rather than reward. Participants in a study were more likely to mete out punishment, even at their own expense, when they were punishing specific, identifiable individuals ("perpetrators").
Vivid, flesh and blood-victims are often more powerful sources of persuasion than abstract statistic (Collins, Taylor, Wood & Thompson, 1988). For example, Ryan White contracted HIV at age 13 and struggled nobly with the disease until succumbing some six year later. Following his death, the US congress passed the Ryan White Care Act, which funds the largest set of services for people living with the AIDS in the country It is clear that Ryan's moving, noble six year struggle with AIDS did more to shift people's attitude about the disease than any amount of statistic or medical arguments.