USES OF THE SKEW-LOGISTIC FUNCTION FOR MULTI-WAVE FUNCTIONS

Abstract

The Skew-Logistic (SL) function has been proposed to model a real-life dynamic process which rises monotonically to peak followed by a monotonic falling back. It was originally introduced to model the first stage of the covid-19 pandemic when it first appeared with the purpose of forecasting the likely behaviour of covid. In its subsequent behaviour, as covid-19 rose and fell under the influence of different controls and with the onset variants, the prevalence and incidence of covid rose and fell repeatedly producing what we might call a Multi-Wave (MW) behaviour, the waves not necessarily the same size. The purpose of the paper is to show how the method of using the SL function for one wave can be easily modified to model the MW situation. To illustrate our extended method, we apply it to two examples. One is to covid -19, to model its most recent behaviour and examine how things might change. We also apply it to climate change, undoubtedly the most serious issue, as without ensuring the world becomes rapidly carbon will bring to and end the known world