Who's the more typical American, Bill Clinton or Barack Obama? According to a European study, the answer depends on who's answering the question. How people see themselves is a potent force that affects how they see others.

The tendency to see those similar to oneself as typical may be a simple, innocuous mental shortcut people use to think of an abstract concept like European. Or it could be an expression of a subtle belief that everyone tends to think their group is better than others

The study posed the question of what the typical European man looked like to natives of Germany and Portugal. Not surprisingly, the Germans thought that the typical European looked more German, while the Portuguese thought that the typical European had a distinctly Portuguese cast.

Other studies have shown that people who belong to a group think that a typical group member has characteristics similar to their own. But those studies were done using words. This one used pictures.

Students from Bonn, Germany (53) and Lisbon, Portugal (50) were shown 770 pairs of male faces on a computer monitor and asked to pick which face in each pair was the more European looking. The faces were composite aggregates of men photographed in Germany and Portugal, with noise added to the photographs to distort the men's features.

After the students had made their selections, the researchers averaged all the images picked by the German students and all the images picked by the Portuguese students to construct two typical European faces.

The average face selected by the Portuguese students was darker, with wide-set eyes and looked more Portuguese, while the average face selected by the German students had lighter hair and looked more German. When shown to independent raters from Germany and Portugal (not the original study participants), the raters confirmed this judgment: the German students had generated a typical European face that looked more German; the Portuguese students had generated one that looked more Portuguese.

The meaning of these results can be interpreted in a couple of ways. The tendency to see those similar to oneself as typical may be a simple, innocuous mental shortcut people use to think of an abstract concept like European. Or it could be an expression of a subtle belief that everyone tends to think their group is better than others, which is less innocuous. It is not yet clear which explanation lies closer to the truth.

And while the researchers see the results as reflecting people's perception of a group they're part of (German, Portuguese), they allow that it could just as well be a projection of people's own individual appearance and not group related at all. The researchers tend to doubt this because about half of the students were female and the faces they were shown were all male.

An article on the study will appear in an upcoming issue of Psychological Science.