It's New Year's Eve, and you've been invited to a large party where there will be lots of people you've never met before. When you arrive, the person hosting the party hands you a blue party hat to wear and you put it on. As you mingle through the crowd, you notice that some people are wearing blue hats like yours, and other people are wearing green party hats.

By the end of the evening, you realize you have spent most of your time with people wearing blue hats. Somehow, they just seemed to be nicer people-they even dance better than those other people wearing green hats.

Moreover, a guy with a green hat bumped into you at one point during the evening and spilled your drink! Given your knowledge of social cognition (and despite the somewhat far-fetched nature of this scenario), how could you explain your perceptions and judgments?