Zero problems with compositional data of physical behaviors: a comparison of three zero replacement methods.

ABSTRACT:

Background

Researchers applying compositional data analysis to time-use data (e.g., time spent in physical behaviors) often face the problem of zeros, that is, recordings of zero time spent in any of the studied behaviors. Zeros hinder the application of compositional data analysis because the analysis is based on log-ratios. One way to overcome this challenge is to replace the zeros with sensible small values. The aim of this study was to compare the performance of three existing replacement methods used within physical behavior time-use epidemiology: simple replacement, multiplicative replacement, and log-ratio expectation-maximization (lrEM) algorithm. Moreover, we assessed the consequence of choosing replacement values higher than the lowest observed value for a given behavior.

SUBMITTER: Rasmussen CL 

PROVIDER: S-EPMC7542467 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature