The present thesis comprises two rather independent chapters. In general, the diagnosis and quantification of dependence is a major aim of econometric studies. Along these lines, the concept of dependence serves as an encompassing framework to analyze time series with two very different...

Based on a cross section of 17 advanced economies and data for the period 1975 to 2015, we examine how the interaction between monetary policy and macroeconomic conditions affects inflation uncertainty in the long-term. We construct a proxy for the unobservable inflation uncertainty based on the...

Standard panel unit root tests (PURTs) are not robust to breaks in innovation variances. Consequently, recent papers have proposed PURTs that are pivotal in the presence of volatility shifts. The applicability of these tests, however, has been restricted to cases where the data contains only an...

Noting that many economic variables display occasional shifts in their second order moments, we investigate the performance of homogenous panel unit root tests in the presence of permanent volatility shifts. It is shown that in this case, panel unit root tests derived under time invariant...

In this dissertation new test statistics for the (panel) unit root hypothesis are presented. Besides a novel approach to testing the unit root hypothesis in univariate time series, the major part of this thesis is dedicated to unit root testing in cross sectionally dependent panels with...