本文拟证明Ｋａｐｐａ系数存在条件极值,并对与此相关的问题作探讨。Ｋａｐｐａ的条件“极值”这里为极值一词加引号是因为,根据两个观察者对二项分类测量结果计算的Ｋａｐｐａ统计量的分布不是连续型的。所以,按严格的数学定义,不能对它讨论极值问题。仅仅是为了叙述的方便,在 In this paper, it is proved that the Kappa coefficient has conditional extremum, and the related problems are discussed. Kappa’s condition “extreme value” is quoted here because the distribution of the Kappa statistic calculated by the two observers on the binomial measurement is not continuous. Therefore, according to a strict mathematical definition, it cannot be discussed with extreme values. Just for the convenience of narrative,