Improving the autodependogram using the Kulback-Leibler divergence

Abstract

The autodependogram is a graphical device recently proposed in the literature to analyze autodependencies. It is defined computing the classical Pearson chi-square statistics of independence at various lags in order to point out the presence lag-depedencies. This paper proposes an improvement of this diagram obtained by substituting the chi-square statistics with an estimator of the Kulback-Leibler divergence between the bivariate density of two delayed variables and the product of their marginal distributions. A simulation study, on well-established time series models, shows that this new autodependogram is more powerful than the previous one. An application to financial data is also shown.

We have decided to withdraw the paper due to a crucial error in equation (9), that is in the definition of the p-value. This invalidates the results reported into the manuscript