Bilker W B, Wang M C
Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia 19104-6021, USA.
Biometrics. 1996 Mar;52(1):10-20.
In many applications, statistical data are frequently observed subject to a retrospective sampling criterion resulting in pure right-truncated data. In classical testing problems, the Mann-Whitney test is used for testing the equality of two distributions. A semiparametric extension of this test is developed for the case when truncation is present. We consider a model in which the truncation distribution is parameterized, while the lifetime distribution is left as a nonparametric component. The method is seen to be applicable to many patterns of truncation including left truncation, right truncation, and doubly truncated data for which no other nonparametric or semiparametric test is currently available. Applications of the semiparametric method are given. Simulation results indicate that for pure right-truncated data the semiparametric test is more powerful than a recent nonparametric test.
在许多应用中，统计数据常常是根据回顾性抽样标准观测得到的，从而产生纯右删失数据。在经典检验问题中，曼-惠特尼检验用于检验两个分布的相等性。针对存在删失的情况，开发了该检验的半参数扩展方法。我们考虑这样一个模型，其中删失分布参数化，而寿命分布作为非参数分量保留。该方法适用于许多删失模式，包括左删失、右删失和双删失数据，目前尚无其他非参数或半参数检验可用于这些数据。给出了半参数方法的应用。模拟结果表明，对于纯右删失数据，半参数检验比最近的非参数检验更具功效性。
