There is a growing literature on unit root testing in threshold autoregressive models. This paper makes two contributions to the literature. First, an asymptotic theory is developed for unit root testing in a threshold autoregression, in which the errors are allowed to be dependent and...

A non-stationary regression model for financial returns is examined theoretically in this paper. Volatility dynamics are modelled both exogenously and deterministic, captured by a nonparametric curve estimation on equidistant centered returns. We prove consistency and asymptotic normality of a...

Diese Anmerkung zeigt, dass das reale Bruttoinlandsprodukt der Bundesrepublik Deutschland einem trendstationären Prozess folgt. Dabei werden sowohl ökonometrische Tests, bei denen die Trendstationarität die Alternativhypothese ist, eingesetzt als auch solche, bei denen sie die Nullhypothese...

This article addresses unit root testing on regulated series through the variance ratio (VR) statistic of Nielsen (2009). The asymptotic distribution of the regulated VR statistic is developed with and without OLS detrending. Results of Cavaliere and Xu (2011) are extended by also developing the...

In this paper we first investigate the validity of a general Value at Risk approach, which is widely used for risk management in banking and insurance companies. We discuss and widely reject the conventional assumptions, e.g. independent identically distributed normal returns, and as consequence...

The purpose of this study is to investigate the validity of the absolute version of the purchasing power parity (PPP) of a sample of four advanced and four emerging countries covering the period from 1993 to 2014. To examine the existence of PPP we apply the Augmented Dickey-Fuller, DF-GLS and...

In this paper, we introduce a set of critical values for unit root tests that are robust in the presence of conditional heteroscedasticity errors using the normalizing and variance-stabilizing transformation (NoVaS) and examine their properties using Monte Carlo methods. In terms of the size of...