3Karpoff.JM.The relation beteween price changes and trading volume:A survey[J].Journalof Financial and Quantitative Analysis.1987.22(1):109-126.
4Stoyu I.Ivanov.The influence of ETFs on the price discovery of gold,silver and oil[J]J Econ Finan(2013)37:453–462.
5Overdahl J A.Mcmillan H.Another day.another collar.An evaluation of the effects of NYSE rule 80A on trading costs and intermar et arbitrage[J].Journal of Business.1998,71:27-53.