The Dark Side of a Big Smile: Detrimental Effects of Smile Intensity on Luxury Brand Advertising Effectiveness
研究发现，在奢侈品广告中，模特中性表情比微笑更能提升广告参与度、点击率和购买行为，因为中性表情增强了对模特能力的判断和广告可信度，这一效应受消费者理性程度和模特视线方向调节。
ABSTRACT The expresser's smile is a ubiquitous nonverbal communication cue used to elicit favorable impressions among consumers. However, does the expresser's smile exert persuasive power in luxury advertising, where exclusivity often outweighs approachability? Integrating the social‐functional perspective of emotions with the stereotype content model of social judgments, we explore how, why, and when the intensity of a smile can adversely impact the effectiveness of luxury advertising. We demonstrate that a neutral expression (vs. a slight and broad smile) leads to higher levels of luxury ad engagement scores, click‐through rates, ad attitudes, and purchase behaviors. This effect is unique to luxury products and driven by a serial processing mechanism: enhanced competence judgments and perceived ad credibility that surface when the expresser features a neutral expression. To provide a deeper understanding of how the persuasive impact of smile intensity vary depending on complementary nonverbal signals and individual level factors, we elucidate two boundary conditions: lay rationalism level of consumers and eye gaze direction of the expresser. Specifically, the detrimental effect of smile intensity on competence perceptions is attenuated for low‐lay rationalistic consumers, who base their decisions on emotions, while the neutral expression facilitates higher ad effectiveness when paired with a direct gaze (vs. an averted gaze). Six preregistered studies, including field data on Instagram ads ( N = 435), two large‐scale field experiments on Meta ( N total = 233,301), and three controlled online experiments ( N total = 940), using different luxury products as well as fictitious and real brands, support these findings. Theoretically, this research advances literature on the nonverbal communication of emotions and the psychology of luxury consumption by showing that smile intensity serves as a visual deterrent to the effectiveness of luxury advertising. Managerially, it offers implications for luxury brand marketers on how to leverage the psychophysical characteristics of facial expressions in their ad design and positioning strategies.