When Judging a Book By Its Cover, You Might Be Right


The old saying goes that we shouldn't judge a book by its cover — that initial impressions of a person or event are often wrong and a true understanding of each requires more details. A new study reveals, however, that first impressions may not be too far off, at least when it comes to our finances.

Three economists conducted a psychological study in which individuals looked at a picture of another person and were asked to rate that person's trustworthiness based on that image. The results of the study were rather surprising.

Economic interactions often imply to gauge the trustworthiness of others. Recent studies showed that when making trust decisions in economic games, people have some accuracy in detecting trustworthiness from the facial features of unknown partners. Here we provide evidence that this face-based trustworthiness detection is a fast and intuitive process by testing its performance at split-second levels of exposure. Participants played a trust game, in which they made decisions whether to trust another player based on their picture. In two studies, we manipulated the exposure time of the picture. We observed that trustworthiness detection remained better than chance for exposure times as short as 100 ms [milliseconds], although it disappeared with an exposure time of 33 ms. We discuss implications for ongoing debates on the use of facial inferences for social and economic decisions.

Will first impressions always be right? No of course not. But sometimes when a certain judgment does come to mind, it's OK to trust your instinct.

Are you guided by your instincts or is the conventional wisdom the way to interact? Tell us below!