A new two-part test based on density ratio model for zero-inflated continuous distributions  

作　　者：LU Ya-hui LIU Ai-yi JIANG Meng-jie JIANG Tao 

机构地区：[1]School of Statistics and Mathematics,Zhejiang Gongshang University,Hangzhou 310018,China [2]Biostatistics and Bioinformatics Branch,Eunice Kennedy Shriver National Institute of China Health and Human Development,Bethesda,MD 20817,USA [3]Hangzhou Commercial College,Zhejiang Gongshang University,Hangzhou 311508,China

出　　处：《Applied Mathematics(A Journal of Chinese Universities)》2020年第2期203-219,共17页高校应用数学学报（英文版）（B辑）

基　　金：Supported by the National Natural Science Foundation of China(No.11971433);the First Class Discipline of Zhejiang-A(Zhejiang Gongshang University-Statistics);the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development.

摘　　要：In this paper,we consider testing the hypothesis concerning the means of two independent semicontinuous distributions whose observations are zero-inflated,characterized by a sizable number of zeros and positive observations from a continuous distribution.The continuous parts of the two semicontinuous distributions are assumed to follow a density ratio model.A new two-part test is developed for this kind of data.The proposed test takes the sum of one test for equality of proportions of zero values and one conditional test for the continuous distribution.The test is proved to follow a2 distribution with two degrees of freedom.Simulation studies show that the proposed test controls the type I error rates at the desired level,and is competitive to,and most of the time more powerful than two popular tests.A real data example from a dietary intervention study is used to illustrate the usefulness of the proposed test.

关 键 词：two-part test zero-in ated continuous distributions density ratio model 

分 类 号：O212.1[理学—概率论与数理统计]