1. Facultad de Medicina Universidad de Atacama Copiapó Chile
2. Departamento de Matemática Universidad de Atacama Copiapó Chile
3. Department of Statistics Federal University of Amazonas Manaus Brazil
4. Department of Epidemiology and Statistics A.C. Camargo Cancer Center São Paulo Brazil
5. Biostatistics and Bioinformatics Research Center Cedars‐Sinai Medical Center Los Angeles California USA