时 间：2023年6月20日（周二）15：00-16：00
地 点: 理科大楼A1514室
题 目：Measurement Error Modeling on Zero-Inflated and Overdispersed Microbiome Sequence Count Data
报告人：王天颖 清华大学统计学研究中心助理教授
主持人：钟琰 助理教授
主 办：统计学院
摘 要：
In microbiome studies, it is of interest to use a sample from a population of microbes, such as the gut microbiota community, to estimate the population proportion of these taxa. However, due to biases introduced in sampling and preprocessing steps, these observed taxa abundances may not reflect true taxa abundance patterns in the ecosystem. Repeated measures, including longitudinal study designs, may be potential solutions to mitigate the discrepancy between observed abundances and true underlying abundances. Yet, widely observed zero-inflation and over-dispersion issues can distort downstream statistical analyses aiming to associate taxa abundances with covariates of interest. In this talk, we present a Zero-Inflated Poisson Gamma (ZIPG) model framework to address these aforementioned challenges. From a perspective of measurement errors, we accommodate the discrepancy between observations and truths by decomposing the mean parameter in Poisson regression into a true abundance level and a multiplicative measurement of sampling variability from the microbial ecosystem. Then, we provide a flexible ZIPG model framework by connecting both the mean abundance and the variability of abundances to different covariates, and build valid statistical inference procedures for both parameter estimation and hypothesis testing. Through comprehensive simulation studies and real data applications, the proposed ZIPG method provides significant insights into distinguished differential variability and mean abundance.
报告人简介：
清华大学统计学研究中心助理教授。她于2018年获得Texas A&M University 统计学博士学位，在哥伦比亚大学生物统计系从事博士后工作，并在2020年加入清华大学。她的研究兴趣包括测量误差分析、分位数回归、高维数据分析，以及统计方法在遗传学和环境科学的应用。