Abstract: In this paper, we improve the results of[2] easily by a transformation and give lower limits which are more concise and stricter. The method is commonly practical, and the bounds of this paper can't be further improved in essence.

Key words: elliptically contoured distribution, best linear unbiased estimate, two-stage estimate

摘要： 本文通过一个变换很简单地改进了文献[2]的结果,并给出了更简明严格的下界。所用的方法具有普遍实用性,且文中的下界已无法再作实质性的改进。

关键词: 椭球等高分布, 最佳线性无偏估计, 两步估计