Covid 19 and A Wavelet Analysis of the Total Deaths per Month in Brazil since 2015

TL;DR

This study applies wavelet analysis to Brazil's monthly death data since 2015 to detect change points, revealing a variance change that predates the COVID-19 pandemic.

Contribution

It demonstrates the use of wavelet transform to identify change points in mortality data, showing that significant variance changes occurred before COVID-19.

Findings

Detected a change point in variance in the death series

Change point occurred before the COVID-19 pandemic

Wavelet analysis effectively identifies historical shifts

Abstract

We investigate the historical series of the total number of deaths per month in Brazil since 2015 using the wavelet transform, in order to assess whether the COVID-19 pandemic caused any change point in that series. Our wavelet analysis shows that the series has a change point in the variance. However, it occurred long before the pandemic began.