Manera, Matteo; Nicolini, Marcella; Vignati, Ilaria - 2013
This paper evaluates how different types of speculation affect the volatility of commodities' futures prices. We adopt …-2010 analyzed at weekly frequency. Using GARCH models we find that speculation significantly affects volatility of returns: short … term speculation has a positive and significant impact on volatility, while long term speculation generally has a negative …