This paper proposes a long-memory model including multiple cycles in addition to the long-run component. Specifically, instead of a single pole or singularity in the spectrum, it allows for multiple poles and thus different cycles with different degrees of persistence. It also incorporates...

This paper analyses the informational efficiency of the WTI crude oil markets using a recently proposed quantitative measure for market inefficiency. The procedure measures the extent to which observed oil price behaviour deviates from the Random Walk benchmark which represents an efficient...