Pengujian dinamika cash price dan cash equivalent price terhadap price discovery dan tingkat konvergensi harga di pasar komoditas berjangka : studi pada kontrak berjangka emas (GOL) di PT Jakarta Futures Exchange periode 2007-2011 = Testing of dynamics cash price and cash equivalent price for identification of price discovery and price convergence rate in commodity futures markets : case at gold future contract (GOL) in PT. Jakarta Futures Exchange period 2007-2011