Assoc Prof Sally Wood
Abstract:
We propose a method for analyzing possibly nonstationary time series by adaptively dividing the time series into an unknown but finite number of segments and estimating the corresponding local spectra by smoothing splines. The model is formulated in a Bayesian framework, and the estimation relies on reversible jump Markov chain Monte Carlo (RJMCMC) methods. For a given segmentation of the time series, the likelihood function is approximated via a product of local Whittle likelihoods. Thus, no parametric assumption is made about the process underlying the time series. The number and lengths of the segments are assumed unknown and may change from one MCMC iteration to another. The frequentist properties of the method are investigated by simulation, and applications to EEG and the El Nino Southern Oscillation phenomenon are described in detail.
Melbourne School of Business, the University of Melbourne
Fri, 07/09/2012 - 4:00pm to 5:00pm
ASB-119, Australian School of Business, UNSW Kensington Campus