A test statistic for graphical modelling of multivariate time series
Faculty of Economics, Tohoku University, 27-1 Kawauchi, Aoba-ku, Sendai 980-8576, Japan. matsuda{at}econ.tohoku.ac.jp
A graphical model for multivariate time series is a concept extended by Dahlhaus (2000) from that for a random vector to a multivariate time series. We propose a test statistic for identifying the model based on the Kullback-Leibler divergence between two graphical models. The null distribution is shown to be asymptotically normal with mean and variance which depend just on the dimensions of the graphs.
Key Words: Asymptotic normality; Backward stepwise selection; Conditional independence; Graphical model; Kullback-Liebler divergence; Periodogram; Spectral density matrix; Test statistic.
Received January 2005. Revised November 2005.