The dynamic structure of profit rates for 156 US manufacturing companies is analyzed by means of fractional integration techniques as an alternative to the commolny used ARMIA models with respect to the "persistence of profits". The results show - despite the short lengths of the series - that...

We analyze by simulation the properties of two time domain and two frequency domain estimators for low order autoregressive fractionally integrated moving average Gaussian models, ARFIMA (p,d,q). The estimators considered are the exact maximum likelihood for demeaned data, EML, the associated...

In this article, simple tests of the random walk hypothesis are proposed that are robust against various kinds of conditional heteroskedasticity, non-stationarities, calendar effects and non-synchronous trading effects. In contrast, conventional tests are usually only robust against conditional...

In practice, it is often impossible to assess the validity of the smoothness assumptions crucial to standard tests for singularities in the spectrum. We therefore propose new tests which are completely insensitive to sharp peaks in the absolutely continuous part of the spectrum. Using Neyman...

This paper extends an optimal frequency domain test for the detection of synchronous patterns in multiple time series to the case of fuzzy patterns, which are not confined to single frequencies or narrow frequency bands. Applying this extension to corn futures with different delivery dates, we...

This paper proposes a modification of an optimal test for cycles in multiple time series and applies it to test the hypothesis that there is a relationship between stock returns and the phases of the moon. No significant relationship is found, which is in line with the evidence from descriptive...

New methods to forecast volatility are usually compared to simple methods like weighted moving averages or GARCH (1, 1) models. In this paper, we provide new benchmark methods which are more accurate but still very simple. In an empirical study of daily returns on major world indices, our new...

This paper first reduces the problem of detecting structural breaks in a random walk to that of finding the best subset of explanatory variables in a regression model and then tailors various subset selection criteria to this specific problem. Of particular interest are those new criteria, which...