Abstract:

Previous studies showed that the attractiveness rating of a face was influenced by context face, which may lead the evaluation to be closer to or far away from the attractiveness of the context, known as assimilation effect or contrast effect. It suggests the influence of context face on target attractiveness evaluation varies and needs to further clarify how it happens. However, there are two problems remain to be solved according to the manner on how the assimilation effect is calculated in previous studies. Firstly, the calculation method of assimilation effect is based on a relative standard by comparing attractiveness ratings of target faces between different contexts (i.e., T1 vs T2), which ignores the initial attractiveness of target face (T0) presented alone. This might lead to an illusive assimilation effect, where both T1 and T2 are far away from T0 and is actually a contrast effect. Secondly, there is a change of assimilation effect associated with the change of target-context difference if an illusive assimilation effect is true. But the change of target-context difference is ignored in previous studies, and how it impact on the attractiveness rating of target face remains unlcear. In this study, the assimilation effect was calculated based on an absolute standard by comparing attractiveness ratings of target faces with their initial attractiveness rated without context. In the experiment, the medium attractive faces was chosen as target face and high-attractive faces as context faces, and the attractiveness difference between the target and the context was changed in a consecutive way. A within-participant design was adopted with the attractiveness difference between the target and the context and exposure time as independent variables. The results found that under highly attractive context faces, individuals' attractiveness ratings of medium target were increased to be closer to the context, resulted in an assimilation effect. In particular, we found the assimilation effect was changed with the attractiveness difference between the target and the context, called the continuum effect in assimilation process. More interestingly, an illusive contrast effect would be concluded if comparing attractiveness ratings between different context without considering th initial attractiveness rating (i.e., a relative standard). That is, the assimilation effect might be mistaken as a contrast effect in previous studies. In addition, the exposure time affected the evaluation of facial attractiveness, and individuals were more inclined to overestimate facial attractiveness in short time.

Key words: facial attractiveness, similarity, assimilation effect, continuum effect