Bootstrap specification tests for diffusion processes

This paper discusses specification tests for diffusion processes. In the one-dimensional case, our proposed test is closest to the nonparametric test of Aı̈t-Sahalia (Rev. Financ. Stud. 9 (1996) 385). However, we compare CDFs instead of densities. In the multidimensional and/or multifactor case, our proposed test is based on comparison of the empirical CDF of actual data and the empirical CDF of simulated data. Asymptotically valid critical values are obtained using an empirical process version of the block bootstrap which accounts for parameter estimation error. An example based on a simple version of the Cox et al. (Econometrica 53 (1985) 385) model is outlined and related Monte Carlo experiments are carried out.