Modeling of Case Increase and Case Fatality Rates Covid-19 in Indonesia Using Biresponse Local Linear Estimator for Longitudinal Data

The coronavirus disease 2019 (COVID-19) outbreak from Wuhan, China has spread very quickly in the world and caused many deaths. In Indonesia, the first case of COVID-19 was reported by the government in March 2020 then it became a pandemic disease. Estimating case increase rate (CIR) and case fatality rates (CFR) are important parameters for studying the basics of pandemic disease. In this paper, we analyse the case increase and case fatality rates of COVID-19 in Indonesia based on longitudinal data and average temperature by using biresponse local linear estimator. The characteristics of case increase and case fatality rates of COVID-19 in each province are different, so locally modeling is more appropriate. The result shows, on average, the highest rate of case increase was in July 2020 and the highest rate of case fatality in August 2020. This happened because of government policies that loosen social distancing programs and increased human mobility due to the holiday in the previous month. Based on average temperature, in November 2020, there were the lowest decreassing CIR and the highest increassing CFR because in November, it entered the rainy season which makes the average temperature lower. It means that the number of COVID-19 cases will be higher if the average temperature is lower.