We propose a new approach to tail analysis for data featuring high degrees of leptokurtosis. Heavy tails can typically be found in financial series, like stock returns or durations between trade arrivals. Our method of tail assessment consists in fitting selected pseudo-models to varying subsets...

We consider representation, estimation and inference on cointegration in a periodic vector autoregressive time series model (PVAR). We show that cointegration amounts to a restriction on a product of parameter matrices. We therefore use GMM to construct estimators of the long-run (cointegration)...