Optimal Estimation of Wasserstein Distance on A Tree with An Application to Microbiome Studies.

ABSTRACT: The weighted UniFrac distance, a plug-in estimator of the Wasserstein distance of read counts on a tree, has been widely used to measure the microbial community difference in microbiome studies. Our investigation however shows that such a plug-in estimator, although intuitive and commonly used in practice, suffers from potential bias. Motivated by this finding, we study the problem of optimal estimation of the Wasserstein distance between two distributions on a tree from the sampled data in the high-dimensional setting. The minimax rate of convergence is established. To overcome the bias problem, we introduce a new estimator, referred to as the moment-screening estimator on a tree (MET), by using implicit best polynomial approximation that incorporates the tree structure. The new estimator

SUBMITTER: Wang S 

PROVIDER: S-EPMC9974173 | biostudies-literature | 2021

REPOSITORIES: biostudies-literature