校园欺凌事件会给学生的身心健康带来严重影响，因此研究校园欺凌的成因机制尤为重要。已有研究表明，学生之间的“力量不平等”是界定校园欺凌的一个重要的因素，由于学生在相互交往过程中会形成各种非正式群体，而非正式群体与非正式群体之间存在地位分层，且这种地位差异容易引发校园欺凌。虽然国内对于非正式群体进行了大量的研究，但是从非正式群体的地位分层关系角度研究校园欺凌还比较罕见，对于非正式群体的研究还存在很多待解决的问题，非正式群体的地位如何分层？非正式群体地位分层和校园欺凌之间存在什么关系？基于此背景，本研究为了填补已有研究的不足，基于社会分层理论和群体动力学理论，运用问卷调查法和访谈法，考察了我国初中生非正式群体地位分层的现状，分析了形成非正式群体地位分层的影响因素，进一步探究了非正式群体地位分层与校园欺凌两者之间的关系。

本研究采取了两种调查方式，第一，以初中生为调查对象，通过采用校园欺凌问卷和非正式群体地位分层量表对珠海市6所初中的24个班级（初一和初二），共1160名初中生进行调查，并结合访谈法，选取4位学生进行访谈；第二，采用回顾性研究的调查方式，调查了珠海市2所大学共367名大学生，试图了解大学生在初中阶段的欺凌情况，以及非正式群体地位分层的状况。

本研究得出如下结论：

1.初中校园欺凌的现象较普遍，有50%的初中生遭遇过校园欺凌，初中校园欺凌类型主要以关系欺凌为主，男生比女生更容易卷入校园欺凌。

2.初中校园普遍存在非正式群体，而且非正式群体之间还存在地位分层的现象。初中生加入非正式群体的比例高达76.2%，超过一半的大学生回忆在初中阶段加入了非正式群体，且非正式群体的地位存在高、中、低之分。

3.初中生非正式群体地位分层主要受到受欢迎程度、领导力、社交力、家庭经济条件和学习成绩五个因素的影响。

4.初中生非正式群体地位分层与校园欺凌呈显著负相关，学生的非正式群体地位越低，则越容易卷入校园欺凌。

5.低地位群体蛮横型对初中生遭遇欺凌/施加欺凌具有正向预测作用，高地位群体社交型对初中生遭遇欺凌具有负向预测作用。

Bullying in schools can have a serious impact on students' physical and mental health, so it is especially important to study the causes and mechanisms of bullying in schools. Studies have shown that "power inequality" among students is an important factor in defining school bullying, as students form various informal groups in the process of interacting with each other, and there are status differences between cliques and subgroups, and such status difference is easy to lead to bullying. Although there is a wealth of research on informal groups in China, it is rare to study school bullying from the perspective of the status relationship of informal groups, there are still many problems to be solved in the study of informal groups. How to stratify the status of informal groups? What relationship could exist between informal groups status stratification and bullying on campus? Based on this background, this study investigated the current situation of informal groups status stratification in junior high schools in China, analyzed the factors influencing the formation of informal groups status stratification, and further explored the relationship between informal groups status stratification and school bullying based on social stratification theory and group dynamics theory, using questionnaire and interview method.

Two types of surveys were used in this study. First, by using the School Bullying Questionnaire and the Informal Groups Status Stratification Scale for junior high school students, a total of 1160 junior high school students from six junior high schools in Zhuhai (24 classes) were surveyed, and combined with the interview method, four students were selected to be interviewed. Second, a recall survey of college students was used to conduct a questionnaire survey on recall of junior high school informal groups status stratification and bullying for 5 classes of 367 college students in 2 universities in Zhuhai.

Based on the above investigation, this study concludes the following.

1. bullying is more common in middle school, with 50% of middle school students experiencing school bullying, and the types of school bullying are mainly relationship bullying, and boys are more likely to be involved in school bullying than girls.

2. The status stratification of informal groups is common in junior high school campuses, and there is a phenomenon of status stratification among informal groups. Up to 76.2% of junior high school students joined the informal group, and more than half of college students recalled that they joined the informal group at the junior high school stage, and the status of informal groups is divided into high, medium and low.

3. The status stratification of the informal group of junior high school students is mainly affected by four factors: popularity, leadership, social skills, family economic conditions and academic performance.

4. Informal group status stratification of junior high school students is negatively correlated with bullying. The lower the status of the informal group of students in the class, the more likely they are to encounter campus bullying.

5. The brutality of low-status groups has a positive predictive effect on junior high school students encountering bullying/inflicting bullying while the social type of high-status groups has a negative predictive effect on junior high school students encountering bullying.