"In the second experiment, the authors selected three Princeton students from among a few dozen student-government leaders, and compared them to three selected

"In the second experiment, the authors selected three Princeton students from among a few dozen student-government leaders, and compared them to three selected representatives of the University of Oregon football team, and three (in their opinion characteristic) young people who did not attend college at all. Experiment 3 tested six new students, three from Yale and three from the University of Arizona, again selected to represent the authors' opinion of what such students should be like. Experiment 4 re-used four of the students from Experiment 3, but substituted two new choices from the same pools. And Experiment 5 re-used five of the six students from Experiment 4, substituting for one participant who seemed on reflection not to be quite of the Right Kind." ...and so on. The usual stuff. http://languagelog.ldc.upenn.edu/nll/?p=7715 http://languagelog.ldc.upenn.edu/nll/?p=7715