Mathematical modeling of voters participation in Indonesia’s 2024 Presidential Election with consideration of unregistered voters in the final voter list

Abstract

Voter participation is a key indicator of the legitimacy of an election. In every electoral cycle, there are individuals who choose not to vote, commonly referred to as abstainers or golongan putih. This behavior may arise from personal choices or administrative issues, particularly when eligible individuals are excluded from the final voter list. This study proposes a mathematical model to examine voter participation in Indonesia's 2024 Presidential Election, particularly incorporating for unregistered voters excluded from the final voter list. The analysis focuses on determining the abstaining-free equilibrium point, the endemic equilibrium point, and the basic reproduction number. The results show that when R_0<1, the system approaches an abstaining-free equilibrium, whereas when R_0>1, an equilibrium including abstainers persists. Numerical simulations indicate that although the model suggests that abstention can be eliminated, it may require a prolonged period under ideal conditions.