“…There exist a wide variety of models in the literature that have been used to model the track geometry degradation between two maintenance cycles and on the basis of recorded measurement data over time or in relation to usage. These models include the linear model (Caetano & Teixeira, 2015;Caetano & Teixeira, 2016;Khajehei et al, 2019;Lee et al, 2018), the exponential model (Peralta et al, 2018;Quiroga & Schnieder, 2012), the grey model (Chaolong, Weixiang, Futian, & Hanning, 2012;Xin, Famurewa, Gao, Kumar, & Zhang, 2016), and the Wiener process (Soleimanmeigouni, Ahmadi, Letot, Nissen, & Kumar, 2016), among other models. In the present study, the exponential model presented in equation (2) has been used to model the track geometry degradation between two maintenance cycles.…”