White students judged their own traits more accurately than those of black students. These results support the theory that members of ethnic minority groups have a greater stake in understanding a more powerful majority population than majority members have in understanding minority groups, Ryan argues. Exaggerations of stereotypical characteristics may arise most commonly when one group perceives another as an enemy, McCauley suggests. For instance, many U.S. citizens held stereotypical caricatures of the Japanese during World War II and vice versa. These highly charged assumptions have since eased on both sides, although negative stereotypes can still arise during conflicts over issues of national importance, such as trade practices.
Stereotypes exert an insidious effect in the schools, another influential line of research suggests.
Children perform much better on achievement and IQ tests if their teachers have positive expectations about their intellectual ability, whereas intellectual decline occurs for kids held in low regard by instructors, these studies find. Robert Rosenthal of Harvard University, who first described this phenomenon in 1968, refers to it as the Pygmalion effect. However, evidence of Pygmalion's classroom shenanigans comes mainly from studies in which teachers were fed information about students whom they had not yet met, notes Jussim. Participating teachers typically have no opportunity to interact with students or observe their achievement over an extended period, he adds. In the real world of elementary education, however, teachers exhibit a good deal of sensitivity to which of their students do and don't have the right academic stuff, according to a project conducted by Jussim and Jacquelynne Eccles of the University of Michigan in Ann Arbor.