Abstract: Social class stereotype is a fixed psychological schema of different social classes. The stereotype content model provides a theoretical framework focusing on the perceived warmth and competence of different social classes. Competence refers to the possibility of the group to realize its intention, which depends on the status of the group (income, wealth, education, job prestige, or title). Warmth represents the group's behavioral intentions, which depend on the willingness to cooperate or the threat of competition. Individuals with high socioeconomic status are perceived ambivalently as competent but cold, whereas Individuals with low socioeconomic status are considered as less competent but warm. Social class stereotypes may affect people’s cognition, emotion, and behaviors. In terms of cognitive effects, social class stereotypes could interfere with memory processes and lead to memory errors during retrieval tasks. In terms of emotional effects, social class stereotypes can help maintain a sense of social justice by positing designating compensatory stereotypes to different classes, in which people with either high or low socioeconomic status have unique advantages. In terms of behavioral effects, social class stereotypes affect students’ performance and impression management strategies. Social class stereotypes could negatively affect students' performance, especially on low-class students doing evaluative tasks. Moreover, in cross-class communication, class stereotypes may affect the choice of impression management strategy. For example, when interacting with subordinates, show tend to project more warmth than competence, whereas when interacting with superiors, they tend to show images with higher competence rather than warmth.
Theories that are often invoked to explain the effects of class stereotypes include the system justification theory and the BIAS map theory. The BIAS map treats "warmth" and "competence" as universal dimensions of stereotypes and emphasizes the direct influence of specific class stereotype content on class interaction. The system justification theory believes that individuals are motivated to justify their own social status, and complimentary class stereotypes could meet such justification motivation. This theory emphasizes the indirect influence of class stereotypes on class interaction. Both the BIAS map and the system justification theory recognize the critical role of social class stereotypes in class interaction. However, ther are fundamental differences between the two theories. According to the BIAS map, class stereotypes may lead to negative emotional experiences and behaviors. In contrast, according to the system justification theory, the complementary stereotypes could cause positive emotional experience as they could preserve a semblance of social justice. The main reason for the disagreement is differences in perspectives specifically. The BIAS map theory considers social class stereotypes to be tools to remain dominant and to justify their monopoly on material or psychological resources, while the system justification theory considers social class stereotypes to be psychological resources to cope with stresses and dissonances caused by unequal social structure.
Future research could (1) clarify the research orientation and the operational definition of class stereotype, (2) expand research on the effects of class stereotype and its intervention strategies, and (3) integrate the theoretical explanations for the effects of class stereotype.

Key words: Class stereotype, Bias map, System justification theory

摘要： 阶层刻板印象是以阶层为分类依据，形成的关于不同阶层的固定心理图式。阶层刻板印象在阶层互动中起着基础性，决定性的作用，决定着人们的认知、情感和行为。偏差地图以“热情”“能力”作为刻板印象统一维度，强调具体阶层刻板印象内容对阶层互动的直接影响。制度正当化理论将阶层刻板印象作为现实合法性的前因变量，强调阶层刻板印象对阶层互动的间接影响。未来研究需要明确阶层刻板印象的操作定义，重视和发掘阶层刻板印象的积极作用，揭示阶层刻板印象后效的心理机制。

关键词: 阶层刻板印象, 偏差地图, 制度正当化理论