A parameter estimator based on Smoluchowski-Kramers approximation

We devise a simplified parameter estimator for a second order stochastic differential equation by a first order system based on the Smoluchowski-Kramers approximation. We establish the consistency of the estimator by using {\Gamma}-convergence theory. We further illus- trate our estimation method by an experimentally studied movement model of a colloidal particle immersed in water under conservative force and constant diffusion.