It is well-known that the presence of serial correlation may result in an inefficient or even biased estimation in time series analysis. In this paper, we consider testing serial correlation when the model error follows a GARCH process which is frequently used in modelling financial data. Two...

In this paper, we propose a simple estimator of cross-covariance matrices for a multivariate time series with an unknown mean based on a linear combination of the circular sample cross-covariance estimator. Our estimator is exactly unbiased when the data generating process follows a Vector...

In this paper, we re-examine two important aspects of the dynamics of relative primary commodity prices, namely the secular trend and the short run volatility. To do so, we employ 25 series, some of them starting as far back as 1650 and powerful panel data stationarity tests that allow for...

In this paper, we derive an optimal test for determining break positions in Gaussian linear regressions. The procedure is an admissible rule in a multiple decision theory setting and the results are exact and valid in small samples. The analysis indicates that regression design can have a very...