Agents With Faces - What Can We Learn From LEGO Minifigures?

Emotional facial expressions are essential for agents. The LEGO company developed hundreds of facial expressions for their Minifigures, which are often the centerpiece of LEGO construction. We investigate and present a summary of the development of the facial expression for all LEGO Minifigures that were released between 1975 and 2010. Our findings are based on several statistical tests that are performed on data gathered from an online questionnaire. The results show that the LEGO company started in 1989 to dramatically increase the variety of facial expressions. The two most frequent expressions are happiness and anger and the proportion of happy faces is decreasing over time. Through a k-cluster analysis we identified six types of facial expression: disdain, confidence, concern, fear, happiness, and anger. Our cluster analysis shows that toy design has become a more complex design space in which the imaginary world of play does not only consist of a simple division of good versus evil, but a world in which heroes are scared and villains can have superior smile. In addition we tested if the perception of the face changes when the face is presented in the context of a complete Minifigure. The impression of anger, disgust, sadness and surprise were significantly influenced by the presence of context information. The distinctiveness of the faces was, however, not significantly improved. The variation in skin color did also not change the perception of the Minifigure’s emotional expression.