This study measures purchasing power parity (PPP) by means of the dynamic-factor errorcorrection model (DF-ECM) approach. Under this new approach, PPP is embedded in latent disequilibrium factors, which are extracted from a large variable set of bilateral price disparities; the factors are then...

Daily futures returns on six important commodities are found to be well described as FIGARCH fractionally integrated volatility processes, with small departures from the martingale in mean property. The paper also analyzes several years of high frequency intra day commodity futures returns and...