This paper argues that typical applications of panel unit root tests should take possible nonstationarity in the volatility process of the innovations of the panel time series into account. Nonstationarity volatility arises for instance when there are structural breaks in the innovation...

General Remarks on Robust Solutions -- Modeling of Uncertainty and Probabilistic Issues -- On Joint Modelling of Random Uncertainty and Fuzzy Imprecision -- On the Approximation of a Discrete Multivariate Probability Distribution Using the New Concept of -Cherry Junction Tree -- Robust Solutions...