Abstract: It present a method for evaluation on justice in grading compositions of enrollment exams and discuss its statistical model. We discovered the distributions of grades of compositions and grades of other questions are similar in Chinese exams. There is a linear correlation between qauntiles of two distribution fuctions. The MLE's of parameters of the linear correlation are asymptotic normal. Finally we presented the EQQ Chart for evaluati on on justice in grading compositions.

Key words: error control, cluster correlation, EQQ chart, control range

摘要： 讨论了对高考作文评分进行监控的一种有效方法，建立了相应的统计模型。高考语文卷的作文分和知识题分具有群体相关，分布的分位数之间有线性关系，由样本得出此线性关系的参数的最小二乘估计。讨论了所得估计的大样本性质。证明估计量是渐近正态的。由此构造出对作文评分进行监控的EQQ控制图。

关键词: 误差控制, 群体相关, EQQ图, 控制带