This study was conducted to determine whether self-differentiation mediates the relationship between parental psychological control of middle school students and the quality of their peer relationships. To this end, a survey was conducted on 300 students in their second or third year of middle school. It included the parental psychological control, self-differentiation, and peer relationship quality scales. The collected data were analyzed to determine whether there was a mediating effect using model 4 of SPSS 21.0 and SPSS PROCESS macro 3.4. There were two major results. The first major result was a significant correlation between parental psychological control, self-differentiation, and the quality of peer relationships. Parental psychological control was significantly negatively correlated with both self-differentiation and the quality of peer relations, and self-differentiation was significantly positively correlated with the quality of peer relationships. The second major result was that self-differentiation fully mediated the relationship between parental psychological control and the quality of peer relationships. These findings confirmed the crucial mediating effect of self-differentiation in the relationship between parental psychological control and peer relationship quality. This study generated primary data about intervention measures that can be used to improve peer relationship quality. This paper discusses the significance and limitations of this study based on its results.
The purposes of this study were to classify procrastination clusters according to active-passive procrastination and procrastination metacognition and to compare differences in problem-solving ability, attribution style, and mental health, defined in terms of life satisfaction, positive emotion and negative emotion, and self-esteem, among procrastination clusters. Data was collected from 230 college students. Cluster analysis showed the existence of diligent task-oriented group, thoughtless passive procrastination group, planned active procrastination group, and ambivalent passive procrastination group. Multivariate variance analysis showed that there were differences between clusters in problem-solving ability, failure attribution style, positive and negative emotions, and self-esteem. Based on these results, implications and suggestions for future research were discussed.