In the Race IAT, subjects are shown a computer screen. The left side of the screen says "White American or Good." The right side says "Black American or Bad." When images and words flash on the screen, the subject uses the keyboard to indicate whether each word or images goes left or right. When a white face appears, you click left. When an African-American face appears, you click right. When a "good" word like "peace" appears, you click left. When a "bad" word like "evil" appears, you click right. So far, so good.

But then the positions switch. Now the left side of the screen says "Black American or Good," and the right side says "White American or Bad." This is when many people start having trouble. They get confused. They make mistakes. When a word like "wonderful" comes up, it takes them longer to correctly put it in the "Black American or Good" category. When a word like "failure" comes up, many people find it harder to group it with "White American or Bad." If that happens, it means you have an automatic preference—an implicit bias—for whites over African-Americans.