本文研究了基于纵向数据的ZIP和ZIB模型的随机效应存在性检验问题.采用score检验方法,得到了可用矩阵表示的score检验统计量.最后,用一个数据实例说明检验方法的有效性.
This article presents tests for existence of random effects in ZIP and ZIB regression models based on longitudinal data. By using score test, the score test statistics are constructed and expressed in simple matrix formulas and a numerical example is given to illustrate our results.