Comparison of hypothesis tests for two means in zero adjusted continuous variables

• Grant number: 22/13340-3
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2023
• End date: October 31, 2023
• Field of knowledge: Physical Sciences and Mathematics - Probability and Statistics - Statistics
• Principal Investigator: Gustavo Henrique de Araujo Pereira
• Grantee: Fernanda Waltrs Freitas
• Host Institution: Centro de Ciências Exatas e de Tecnologia (CCET). Universidade Federal de São Carlos (UFSCAR). São Carlos , SP, Brazil

Abstract

Variables that are discrete at zero and continuous at some interval of the positive real numbers are commonly studied in many areas of knowledge. They are known as zero adjusted continuous variables. As for other types of variables, it is usually desirable to compare the mean of a zero adjusted continuous variable in two populations. However, the proposed tests for this type of variable assume that the distribution of the studied variable is known or they are not simple and are not available in any statistical software. In this work, we will use Monte Carlo simulation studies to compare the performance of Welch's test and three tests based on bootstrap to compare two means of a zero adjusted continuous variable in independent samples. The null rejection rate and the power of the tests will be evaluated in several scenarios. An application to real data will illustrate the usefulness of the developed simulation studies.