When water resource or quality problems associated with phreatic water in geological settings are studied, information a......

据线性模型原理,提出了利用协变量改进作物新品种性状表现方差估计的方法,指出了方差估计效果评价的指标,在此基础上,分析讨论了利......

对截断变量适当修正后，给出了协变量Ⅰ型截尾时期望的无偏估计．并证明了其方差在一定条件下小于开窗法得到的方差，从而提高了线型模型......

It is often important to incorporate covariate information in the design of clinical trials. In literature there are man......