Three parameter gamma-type growth curve, using a stochastic gamma diffusion model: Computational statistical aspects and simulation

In this paper, we propose a new model of a three-parameter stochastic growth, based on a stochastic gamma diffusion process, with a third, threshold, parameter. This model can be considered a stochastic version of a three-parameter deterministic growth curve, structured such that its trend function is of the type given by this same growth curve. We develop the statistical inference of this model on the basis of maximum likelihood methodology, analysing on simulated data the computational problem associated with the threshold parameter, a problem that is of great importance in its application to real data.