中文摘要：

采用母亲报告的方法，对1618名儿童的攻击进行了4年（9岁～12岁）的追踪研究，分析了童年中晚期攻击的一般发展轨迹、亚组发展轨迹以及性别差异。结果发现：（1）总体上，童年中晚期儿童的攻击水平随年龄而下降。（2）基于亚组的准参数模型分析表明，童年中晚期母亲报告的儿童攻击呈现三条不同的发展轨迹，即无攻击轨迹、低攻击一下降轨迹以及持续高攻击轨迹，各轨迹组人数比例分别约为68．7％、26．8％、4．5％。持续高攻击轨迹组以及低攻击一下降轨迹组的儿童在童年晚期均面临一定程度的人际适应困难。（3）多项Logit模型以及卡方检验表明，男生更倾向于归属于攻击轨迹组（高或者低攻击轨迹组），而女生更倾向于归属于无攻击轨迹组；但这并不说明高攻击轨迹组中没有女生，约2％的女生属于高攻击轨迹组。

英文摘要：

The development and control of childhood aggression have been among topics that received the most attentions from researchers for more than half a century. Especially in recent years, with violence being recognized as a primary and increasingly important public health priority, research in this area has been further promoted and the amount of research has kept rapidly growing. The last decade has witnessed a transformation of research interest from the average development to the individual difference in the development of aggression, and the extant research indicated that although during middle and late childhood, physical aggression decreases for most children and many refrain entirely, some continue to engage in high level of aggression. Recent person-centered longitudinal studies in western countries demonstrated that children followed different development trajectories in development of aggression and other forms of externalizing problem behaviors. However, empirical evidence on the developmental trajectories of children＇s aggression in non-western cultures has been rare. In the view that systematic information regarding the development of aggression of Chinese children has been highly limited, the present study explored the development and gender differences of aggression during middle and late childhood among Chinese urban children by using both variable-centered methods and person-centered methods. Three specific questions were addressed： （1） the general developmental pattern, （2） the typical developmental trajectories that different children would follow, and （3） the possible gender differences in the above aspects. Approximately 2000 children from 36 classes of I I primary schools in Jinan City, Shandong Province were followed from grade 3 （average age 9.26 _.＋ 0.29 years） till grade 6. Children＇s mothers reported their aggression on five items from the Aggression subscale of CBCL annually. 1618 students have complete records on at least 3 waves of data collection, among which